Electrical Gremlins!!
11-10-10, 06:50 PM
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Electrical Gremlins!!
To all of those who have in the past, are right now, or will in the future deal with electrical gremlins...I feel for you!
Right now I have:
-varying voltage from the alternator. tested good, it's putting out 14v. but my gauge typically reads about 12.5 volts when it's started up, then rises to 14v after I press the accelerator, but drops at times while driving, typically while stopping at a red light or stop sign. Belt is tight, wires on the alternator are tight, battery terminals tight.
-with car running, press the breaks and the lights will dim (all lights inside and headlights if on). Radio will also sometimes turn off and pulse on and off until breaks are released.
-radio used to not work at all after the car sat for a year and a half until I cleaned all the ground (except the ECU ground). Then it worked unless I pressed the breaks. Cleaned the ECU ground and now most of the time it stays on except random times the breaks will effect it.
-air control (heater) - most of the time when turned on the air will be moving very slowly even at max. hit the side of the center console at the side of the control unit and air will flow normal for the setting
-if lights for cluster panel are dimmed, sometimes wiggling the cruise control box will cause the lights to brighten. if they are turned all the way up...sometimes they will be dim (no wiggling involved)
-biggest aggravation of them all: 3800 rpm hesitation. I cleaned all grounds to the car including the ecu ground and it didn't fix it. I was going to begin exploring other options such as damaged wires, bad connections, anything else. But one day I peeled out of a gas station and suddenly they were working! I drove the car about 100 miles and they continued to work. I even drove it with intention of knocking wires loose if that was my problem. I hit every bump I could find, railroad tracks and took corners hard and they continued to work. Until....I took a left turn on my way home but it was shamefully executed. I jerked the car a little too hard when I released the clutch and reengaged the tranny and put it in too high of gear and lost speed in my turn because I dropped below my power band. Well, when I accelerated out, my secondary injectors were no longer firing. Next day I pull out of my driveway and they are working. I drive to the store and they continue to work until I get there. When I left, they weren't working.
Everything I have done, checked all connections including grounds for looseness or being dirty. Cleaned as much as I could and all connections seem solid. I looked at the wires to the ECU and they look in much better shape then under the hood. I have not removed any dash panels to look at those wires.
Some questions if they might be answered? Would a bad battery cause most of these problems? Also, is there anything I can check for my secondary injectors? I cannot afford part swapping as a means of diagnosing the problem. I am hoping it's not my ECU itself. Also, everything was working fine before the car sat for a year and a half because of a bad transmission. I was only able to start it up and let it run to keep the engine sound.
Thanks.
Right now I have:
-varying voltage from the alternator. tested good, it's putting out 14v. but my gauge typically reads about 12.5 volts when it's started up, then rises to 14v after I press the accelerator, but drops at times while driving, typically while stopping at a red light or stop sign. Belt is tight, wires on the alternator are tight, battery terminals tight.
-with car running, press the breaks and the lights will dim (all lights inside and headlights if on). Radio will also sometimes turn off and pulse on and off until breaks are released.
-radio used to not work at all after the car sat for a year and a half until I cleaned all the ground (except the ECU ground). Then it worked unless I pressed the breaks. Cleaned the ECU ground and now most of the time it stays on except random times the breaks will effect it.
-air control (heater) - most of the time when turned on the air will be moving very slowly even at max. hit the side of the center console at the side of the control unit and air will flow normal for the setting
-if lights for cluster panel are dimmed, sometimes wiggling the cruise control box will cause the lights to brighten. if they are turned all the way up...sometimes they will be dim (no wiggling involved)
-biggest aggravation of them all: 3800 rpm hesitation. I cleaned all grounds to the car including the ecu ground and it didn't fix it. I was going to begin exploring other options such as damaged wires, bad connections, anything else. But one day I peeled out of a gas station and suddenly they were working! I drove the car about 100 miles and they continued to work. I even drove it with intention of knocking wires loose if that was my problem. I hit every bump I could find, railroad tracks and took corners hard and they continued to work. Until....I took a left turn on my way home but it was shamefully executed. I jerked the car a little too hard when I released the clutch and reengaged the tranny and put it in too high of gear and lost speed in my turn because I dropped below my power band. Well, when I accelerated out, my secondary injectors were no longer firing. Next day I pull out of my driveway and they are working. I drive to the store and they continue to work until I get there. When I left, they weren't working.
Everything I have done, checked all connections including grounds for looseness or being dirty. Cleaned as much as I could and all connections seem solid. I looked at the wires to the ECU and they look in much better shape then under the hood. I have not removed any dash panels to look at those wires.
Some questions if they might be answered? Would a bad battery cause most of these problems? Also, is there anything I can check for my secondary injectors? I cannot afford part swapping as a means of diagnosing the problem. I am hoping it's not my ECU itself. Also, everything was working fine before the car sat for a year and a half because of a bad transmission. I was only able to start it up and let it run to keep the engine sound.
Thanks.
11-10-10, 07:21 PM
#2
To all of those who have in the past, are right now, or will in the future deal with electrical gremlins...I feel for you!
Right now I have:
-varying voltage from the alternator. tested good, it's putting out 14v. but my gauge typically reads about 12.5 volts when it's started up, then rises to 14v after I press the accelerator, but drops at times while driving, typically while stopping at a red light or stop sign. Belt is tight, wires on the alternator are tight, battery terminals tight.
-with car running, press the breaks and the lights will dim (all lights inside and headlights if on). Radio will also sometimes turn off and pulse on and off until breaks are released.
-radio used to not work at all after the car sat for a year and a half until I cleaned all the ground (except the ECU ground). Then it worked unless I pressed the breaks. Cleaned the ECU ground and now most of the time it stays on except random times the breaks will effect it.
-air control (heater) - most of the time when turned on the air will be moving very slowly even at max. hit the side of the center console at the side of the control unit and air will flow normal for the setting
-if lights for cluster panel are dimmed, sometimes wiggling the cruise control box will cause the lights to brighten. if they are turned all the way up...sometimes they will be dim (no wiggling involved)
-biggest aggravation of them all: 3800 rpm hesitation. I cleaned all grounds to the car including the ecu ground and it didn't fix it. I was going to begin exploring other options such as damaged wires, bad connections, anything else. But one day I peeled out of a gas station and suddenly they were working! I drove the car about 100 miles and they continued to work. I even drove it with intention of knocking wires loose if that was my problem. I hit every bump I could find, railroad tracks and took corners hard and they continued to work. Until....I took a left turn on my way home but it was shamefully executed. I jerked the car a little too hard when I released the clutch and reengaged the tranny and put it in too high of gear and lost speed in my turn because I dropped below my power band. Well, when I accelerated out, my secondary injectors were no longer firing. Next day I pull out of my driveway and they are working. I drive to the store and they continue to work until I get there. When I left, they weren't working.
Everything I have done, checked all connections including grounds for looseness or being dirty. Cleaned as much as I could and all connections seem solid. I looked at the wires to the ECU and they look in much better shape then under the hood. I have not removed any dash panels to look at those wires.
Some questions if they might be answered? Would a bad battery cause most of these problems? Also, is there anything I can check for my secondary injectors? I cannot afford part swapping as a means of diagnosing the problem. I am hoping it's not my ECU itself. Also, everything was working fine before the car sat for a year and a half because of a bad transmission. I was only able to start it up and let it run to keep the engine sound.
Thanks.
Right now I have:
-varying voltage from the alternator. tested good, it's putting out 14v. but my gauge typically reads about 12.5 volts when it's started up, then rises to 14v after I press the accelerator, but drops at times while driving, typically while stopping at a red light or stop sign. Belt is tight, wires on the alternator are tight, battery terminals tight.
-with car running, press the breaks and the lights will dim (all lights inside and headlights if on). Radio will also sometimes turn off and pulse on and off until breaks are released.
-radio used to not work at all after the car sat for a year and a half until I cleaned all the ground (except the ECU ground). Then it worked unless I pressed the breaks. Cleaned the ECU ground and now most of the time it stays on except random times the breaks will effect it.
-air control (heater) - most of the time when turned on the air will be moving very slowly even at max. hit the side of the center console at the side of the control unit and air will flow normal for the setting
-if lights for cluster panel are dimmed, sometimes wiggling the cruise control box will cause the lights to brighten. if they are turned all the way up...sometimes they will be dim (no wiggling involved)
-biggest aggravation of them all: 3800 rpm hesitation. I cleaned all grounds to the car including the ecu ground and it didn't fix it. I was going to begin exploring other options such as damaged wires, bad connections, anything else. But one day I peeled out of a gas station and suddenly they were working! I drove the car about 100 miles and they continued to work. I even drove it with intention of knocking wires loose if that was my problem. I hit every bump I could find, railroad tracks and took corners hard and they continued to work. Until....I took a left turn on my way home but it was shamefully executed. I jerked the car a little too hard when I released the clutch and reengaged the tranny and put it in too high of gear and lost speed in my turn because I dropped below my power band. Well, when I accelerated out, my secondary injectors were no longer firing. Next day I pull out of my driveway and they are working. I drive to the store and they continue to work until I get there. When I left, they weren't working.
Everything I have done, checked all connections including grounds for looseness or being dirty. Cleaned as much as I could and all connections seem solid. I looked at the wires to the ECU and they look in much better shape then under the hood. I have not removed any dash panels to look at those wires.
Some questions if they might be answered? Would a bad battery cause most of these problems? Also, is there anything I can check for my secondary injectors? I cannot afford part swapping as a means of diagnosing the problem. I am hoping it's not my ECU itself. Also, everything was working fine before the car sat for a year and a half because of a bad transmission. I was only able to start it up and let it run to keep the engine sound.
Thanks.
The pressing of the brake pedal draws enough voltage from the alternator that it's not strong enough to power up everything. Disconnect the brake switch on the pedal and press the brake pedal with the lights on and the lights will probably not dim. The voltage gauge is not that accurate especially as it ages. The best way to measure the voltage is at the alternator itself. A higher amped alternator would likely fix this.
The 3800 rpm is either a ground problem or the wiring to the secondary injectors is faulty. It's best to add an additional ground at the four ground wires at the ECU. Pin 3A,3G,2C and 2R. Regrounding the engine ground works best when that ground wire is making a good connection to the ECU. What if the ground wire does not have a good connection to the ECU? Would regrounding it offer any help? Probably not.
Try regrounding the radio wire and see if it helps this issue. Where the center console bolts to the body is an excellent grounding point. Located beneath the plastic panel on either side of the console and just underneath the carpeting.
11-10-10, 07:55 PM
#3
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at 3800 the primaries are doing their job and cutting back half, but the secondaries are not coming on. What suddenly started working was my secondaries actually coming online and fully functioning. Then, as described above, they stopped coming on again, etc. I cleaned all grounds and moved one of my grounds to connect directly to the ECU ground under the UIM. This ground was previously wired to the side of the UIM on it's own. It is ran directly from the battery. Today I pulled the carpet and panel away from the ECU to check the wires. I see there is already 2 ground wires spliced into one of the ground wires on one of the connectors to the ECU. I don't know where these additional ground wires run to. All the wires I can see inside the car in this location look really good and it looks like everything has good connection. I can gather some pics and post.
I definitely plan to pull the dash out soon and work on the wires under there and reground the radio. Thanks for the advice on that one.
I definitely plan to pull the dash out soon and work on the wires under there and reground the radio. Thanks for the advice on that one.
11-10-10, 08:06 PM
#4
at 3800 the primaries are doing their job and cutting back half, but the secondaries are not coming on. What suddenly started working was my secondaries actually coming online and fully functioning. Then, as described above, they stopped coming on again, etc. I cleaned all grounds and moved one of my grounds to connect directly to the ECU ground under the UIM. This ground was previously wired to the side of the UIM on it's own. It is ran directly from the battery. Today I pulled the carpet and panel away from the ECU to check the wires. I see there is already 2 ground wires spliced into one of the ground wires on one of the connectors to the ECU. I don't know where these additional ground wires run to. All the wires I can see inside the car in this location look really good and it looks like everything has good connection. I can gather some pics and post.
I definitely plan to pull the dash out soon and work on the wires under there and reground the radio. Thanks for the advice on that one.
I definitely plan to pull the dash out soon and work on the wires under there and reground the radio. Thanks for the advice on that one.
11-10-10, 08:47 PM
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I bought the car 3 years ago from a guy who put a new engine in it so he did all the work. I'm not completely certain what all he did so this has been a treasure hunt for me. I also don't have much of a clue what I'm doing other then my basic knowledge of wiring and mechanics skills.
11-10-10, 08:53 PM
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Now, I do plan on having my husband (the actual electrician) to take a multimeter to all the wires to determine if there is a bad wire in the bundles (saves me from taking the bundles apart). Otherwise I am still trying to research and find everything related to this problem that I can have him test. It's an amazing system...when it works, but again because I don't know this car much at all, I am still trying to figure out all the little pieces to the puzzle.
11-13-10, 01:54 PM
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Okay...
So I had a funny feeling about my alternator and decided to take it down to Advance Auto in town and have it tested.
The diod is bad and something about the voltage regular not functioning properly. Meaning that when the machine was running, the diod indicator light was coming on and off and when they pressed the button for the voltage regular and instead of the voltage dropping to zero it maintained at 14 volts. The manager was called over to verify and she mentioned something about it's putting out too much current.
So...I think this may be the cause of most of my problems. Could it also be a strong possibility it's causing my secondary injectors to not come on?
So I had a funny feeling about my alternator and decided to take it down to Advance Auto in town and have it tested.
The diod is bad and something about the voltage regular not functioning properly. Meaning that when the machine was running, the diod indicator light was coming on and off and when they pressed the button for the voltage regular and instead of the voltage dropping to zero it maintained at 14 volts. The manager was called over to verify and she mentioned something about it's putting out too much current.
So...I think this may be the cause of most of my problems. Could it also be a strong possibility it's causing my secondary injectors to not come on?
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11-13-10, 02:14 PM
#8
Okay...
So I had a funny feeling about my alternator and decided to take it down to Advance Auto in town and have it tested.
The diod is bad and something about the voltage regular not functioning properly. Meaning that when the machine was running, the diod indicator light was coming on and off and when they pressed the button for the voltage regular and instead of the voltage dropping to zero it maintained at 14 volts. The manager was called over to verify and she mentioned something about it's putting out too much current.
So...I think this may be the cause of most of my problems. Could it also be a strong possibility it's causing my secondary injectors to not come on?
So I had a funny feeling about my alternator and decided to take it down to Advance Auto in town and have it tested.
The diod is bad and something about the voltage regular not functioning properly. Meaning that when the machine was running, the diod indicator light was coming on and off and when they pressed the button for the voltage regular and instead of the voltage dropping to zero it maintained at 14 volts. The manager was called over to verify and she mentioned something about it's putting out too much current.
So...I think this may be the cause of most of my problems. Could it also be a strong possibility it's causing my secondary injectors to not come on?
The smallest ECU plug, which houses the injector wires, can be disconnected from the ECU and then at the secondary injectors as well (injector clip disconnected) and a continuity/ohm test can be run to see if the wires are up to spec. If so and the LED test is positive then the problem is in the injector clip not making good contact with the injector or the injectors themselves or load is not being sensed by the ECU.
11-13-10, 03:00 PM
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Probably not. Check the Black/Yellow wire at the secondaries for voltage w/key to on as it should have battery voltage. Check pin 3H and 3F at the ECU for battery voltage w/key to on. Disconnect the vacuum hose to the pressure sensor and plug it. Disconnect the TPS plug. This will simulate load which is necessary for the secondaries to operate. Then take a Radio Shack LED and place the negative LED wire into the back of either pin 3H or 3F and the positive LED wire into the back of pin 3I of the ECU. Then start the car and rev it and if the ECU fires the proper signal to the injector the light will flash repeatedly.
The smallest ECU plug, which houses the injector wires, can be disconnected from the ECU and then at the secondary injectors as well (injector clip disconnected) and a continuity/ohm test can be run to see if the wires are up to spec. If so and the LED test is positive then the problem is in the injector clip not making good contact with the injector or the injectors themselves or load is not being sensed by the ECU.
The smallest ECU plug, which houses the injector wires, can be disconnected from the ECU and then at the secondary injectors as well (injector clip disconnected) and a continuity/ohm test can be run to see if the wires are up to spec. If so and the LED test is positive then the problem is in the injector clip not making good contact with the injector or the injectors themselves or load is not being sensed by the ECU.
Also noticed while it was behaving this way the gauge on my alternator was dropping almost in sink. When I stopped, the gauge was reading at 12v and my radio stopped working while I held the brakes and when I began to pull away I heard a belt squeal. This why I had the alternator tested.This problem is so wild and random with me. It's driving me crazy
I'll get the tester on it and see what I can figure out.
11-13-10, 07:37 PM
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suscribing to this as my car car has the random brake voltage drop problem too.
not as bad as yours is though, but still slightly annoying.
might go get my alternator checked to see if we have that in common.
not as bad as yours is though, but still slightly annoying.
might go get my alternator checked to see if we have that in common.
11-13-10, 10:36 PM
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I had some other warning signs to a bad alt. It gets blazing hot after running for a little while; you can't touch it for more then a second, and there's a black powder residue all over it (primarily under the pulley). I'm assuming the powder and burn-off or rubbed off the belt because it's maybe seizing and causing it to slip.
I hope you manage to track it down. This electrical stuff can drive you bonkers.
11-14-10, 01:52 PM
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I also suggest checking the quality of the battery terminal connectors and the wiring from the alternator to your battery and the grounds. I had a SUPER bad issue with this until I cleaned every ground in under the hood and changed the terminal connectors. The old ones were wore out to say the least. They had stretched to being loose when all the way tightened and had some corrosion. All of this improved it and did much better (ie: at least stuff worked). But it was still acting up so that's why I had the alternator tested.
I had some other warning signs to a bad alt. It gets blazing hot after running for a little while; you can't touch it for more then a second, and there's a black powder residue all over it (primarily under the pulley). I'm assuming the powder and burn-off or rubbed off the belt because it's maybe seizing and causing it to slip.
I hope you manage to track it down. This electrical stuff can drive you bonkers.
I had some other warning signs to a bad alt. It gets blazing hot after running for a little while; you can't touch it for more then a second, and there's a black powder residue all over it (primarily under the pulley). I'm assuming the powder and burn-off or rubbed off the belt because it's maybe seizing and causing it to slip.
I hope you manage to track it down. This electrical stuff can drive you bonkers.
used to be really bad but cleaning them fixed a lot.
was debating getting all new wires, alt, and battery but until it gives me another major problem i see no reason to right now.
11-14-10, 02:44 PM
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Anyway, replacing the wires can be either a pain in the butt or expensive depending on the route you take. A new engine harness (like from mazdatrix) is over $700. Of course you can splice out wires but that can be a lot of work.
11-14-10, 02:54 PM
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I wouldn't worry about replacing the wires unless everything else checks out good and you have tested the voltage or continuity being sent and being received. Unless you significant drop of power through the wires to each locating (connector) your wires are good. I haven't gotten around to checking mine yet. My husband is the electrician here but he has been working a huge amount because of a massive inspection going on right now (he's military). So I have been doing what I can until he has time to take the testers and multimeter to everything. My job is checking everything for solid connections, obvious defects, cleanliness, and research (both on here and in the field driving the car for observation).
Anyway, replacing the wires can be either a pain in the butt or expensive depending on the route you take. A new engine harness (like from mazdatrix) is over $700. Of course you can splice out wires but that can be a lot of work.
Anyway, replacing the wires can be either a pain in the butt or expensive depending on the route you take. A new engine harness (like from mazdatrix) is over $700. Of course you can splice out wires but that can be a lot of work.
mainly just the battery wires as i suspect some corrosion has taken place within.
also inspecting and cleaning up all my grounds.
11-14-10, 02:58 PM
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Of course. lol. I've noticed some of the people in these threads can be a little extreme. I meant nothing by it. But yeah, sounds like a good idea if they can't be cleaned up.
11-14-10, 06:15 PM
#16
I have never owned an S4, but on the S5, we have all the relays lined up on a bracket next to the hood latch.
I would check the relays, more specifically the dimmer one. Then trace back to the Main fuse box. There could be a few frayed wires causing the problem.
I would check the relays, more specifically the dimmer one. Then trace back to the Main fuse box. There could be a few frayed wires causing the problem.
11-14-10, 06:26 PM
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Thanks Ryan, I will check on that. If I have those relays that could be a possibility for me especially since the car suffered a hit in the front. My problems didn't start after the hit, but it could have damaged it and while the car sat for a year it could have corroded.
I'll post my findings!
I'll post my findings!
11-14-10, 06:49 PM
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Update:
All relays look solid. I pulled the connectors and all wires seem to be solid inside the clips, no looseness, they are very clean and the clips do not appear to be internally damaged. How would I test if the relays themselves are good or bad? If this is a possibility, it would not be in the wires or connectors to the relays.
Thanks
All relays look solid. I pulled the connectors and all wires seem to be solid inside the clips, no looseness, they are very clean and the clips do not appear to be internally damaged. How would I test if the relays themselves are good or bad? If this is a possibility, it would not be in the wires or connectors to the relays.
Thanks
11-14-10, 07:00 PM
#19
Update:
All relays look solid. I pulled the connectors and all wires seem to be solid inside the clips, no looseness, they are very clean and the clips do not appear to be internally damaged. How would I test if the relays themselves are good or bad? If this is a possibility, it would not be in the wires or connectors to the relays.
Thanks
All relays look solid. I pulled the connectors and all wires seem to be solid inside the clips, no looseness, they are very clean and the clips do not appear to be internally damaged. How would I test if the relays themselves are good or bad? If this is a possibility, it would not be in the wires or connectors to the relays.
Thanks
11-14-10, 07:30 PM
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Thanks satch!
11-14-10, 09:36 PM
#21
I'm sorry to say this, but you're never going to fix this problem unless you replace every connector and relay on your car, and probably over 95% of the wiring.
Think about it. How many connections that AREN'T weatherproof are there? How many relays that have 20+ years of arc buildup are there? The sad truth is that all those spots cause high resistance connections, which sum up to one thing: voltage drops.
I know this because I had the same problem. I got so sick of hitting the brake pedal and having my damn radio cut off. Then seconds later, it would kick back on, but that initial touch of the brake pedal straight up killed the radio. Had the 3800 rpm thing too. I band-aided the problem at first with some LED brake lights. Stopped killing the radio, I'll give it credit there. Every time I hit the brake pedal, the "light out" light would illuminate. To fix that, I pulled that light bulb out.
Ultimate fix? FD alternator. Turns out, the stock S4 alternator sucks, but tests out perfectly fine every time you try. It'll kill the battery, screw with your whole car's electronics, etc. It's a simple swap, I highly recommend looking into it. 3800 rpm hesitation went away for the most part.
Ultimate fix for 3800 rpm hesitation? Standalone ecu. Last headache you'll ever have to endure is wiring it in.
Think about it. How many connections that AREN'T weatherproof are there? How many relays that have 20+ years of arc buildup are there? The sad truth is that all those spots cause high resistance connections, which sum up to one thing: voltage drops.
I know this because I had the same problem. I got so sick of hitting the brake pedal and having my damn radio cut off. Then seconds later, it would kick back on, but that initial touch of the brake pedal straight up killed the radio. Had the 3800 rpm thing too. I band-aided the problem at first with some LED brake lights. Stopped killing the radio, I'll give it credit there. Every time I hit the brake pedal, the "light out" light would illuminate. To fix that, I pulled that light bulb out.
Ultimate fix? FD alternator. Turns out, the stock S4 alternator sucks, but tests out perfectly fine every time you try. It'll kill the battery, screw with your whole car's electronics, etc. It's a simple swap, I highly recommend looking into it. 3800 rpm hesitation went away for the most part.
Ultimate fix for 3800 rpm hesitation? Standalone ecu. Last headache you'll ever have to endure is wiring it in.
11-14-10, 09:56 PM
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Ultimate fix? FD alternator. Turns out, the stock S4 alternator sucks, but tests out perfectly fine every time you try. It'll kill the battery, screw with your whole car's electronics, etc. It's a simple swap, I highly recommend looking into it. 3800 rpm hesitation went away for the most part.
Thanks for the thoughts!
11-14-10, 10:06 PM
#24
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I have checked the ECU ground. On this car I was able to get to it by simply removing the solenoid and the bracket for the UIM and access it. I also added a ground to it. The car has already had ground added to it and one of them ran from the battery to the UIM so I simply moved it to the ECU ground. It was loose and showed evidence of arching when I got to it. It's been cleaned up nice and shiny and replaced. About 100 miles later my secondaries managed to come on again for the first time in a long time but they won't stay on and as more time goes they are working less often. I am thinking my alternator could be a cause since every time they don't work, I'm showing less voltage from the alternator. Of course I could be wrong, but everything I know about electricity says if I'm not getting enough power to begin with, stuff won't work right.
One other question. With replacing my alt with a FD alt. Which is the best year to go with? Does the year matter? And are all of them turbo charged? I'm looking at oreilly auto and it doesn't give me an option. I'm running an N/A.
One other question. With replacing my alt with a FD alt. Which is the best year to go with? Does the year matter? And are all of them turbo charged? I'm looking at oreilly auto and it doesn't give me an option. I'm running an N/A.
11-14-10, 10:27 PM
#25
A faulty alt will cause all sorts of chaos.
We had one go out and it was erratically giving too many volts, and the ecu would turn on everything at 3x times high speed (front and back wipers, all the instrument lights, etc.) all the while the car would bog down and nearly die. This usually occured while turning in an intersection and was quite a problem.
We had one go out and it was erratically giving too many volts, and the ecu would turn on everything at 3x times high speed (front and back wipers, all the instrument lights, etc.) all the while the car would bog down and nearly die. This usually occured while turning in an intersection and was quite a problem.