More S5 wiring questions, no tach, no spark, no go.
01-22-05, 09:44 PM
#1
More S5 wiring questions, no tach, no spark, no go.
Ok well I am running out of ideas here. I am starting to question the ecu and wiring harness, not to mention every electrical aspect of the car.
The issue is that I have no spark, no working tach, and I still need to check to see if the injectors are firing. I have tried replacing the CAS and testing the in car one per FSM, and no change. I have also checked the coils per FSM and checked for 12v at the coil, and the 5v reference voltage at the boost sensor. I have checked every ground and tried 3 different ecu's (n370 and 2 n374).
The vehical has several odd quirks too, for instance if you move the shifter...... the power antenna goes up and down. I noticed several dosconnected sensors under the vehical, and on the tranny. What is there has been wired using a household extension cords 14guage stranded wire. (What was left was still in the rear.... lol).
The chasis ground wire (black with yellow stripe) is connected, to the body, but I had to run my own 8guage wire to the ground point on the strut tower. The main ground wire for the block was not there, and a 4guage wire ran from the alternator bracket had taken its place. I have moved this to one of the block bolts on the AC bracket (I dont have any longer wire). The car cranks fine and has 115-115 compression per rotor per face.
I think I need to either pull the motor, redo the grounds correctly and check ALL the body wiring, and then figure out what to do about the no spark.
Any input welcome, thanks guys, its becoming a headache.
The issue is that I have no spark, no working tach, and I still need to check to see if the injectors are firing. I have tried replacing the CAS and testing the in car one per FSM, and no change. I have also checked the coils per FSM and checked for 12v at the coil, and the 5v reference voltage at the boost sensor. I have checked every ground and tried 3 different ecu's (n370 and 2 n374).
The vehical has several odd quirks too, for instance if you move the shifter...... the power antenna goes up and down. I noticed several dosconnected sensors under the vehical, and on the tranny. What is there has been wired using a household extension cords 14guage stranded wire. (What was left was still in the rear.... lol).
The chasis ground wire (black with yellow stripe) is connected, to the body, but I had to run my own 8guage wire to the ground point on the strut tower. The main ground wire for the block was not there, and a 4guage wire ran from the alternator bracket had taken its place. I have moved this to one of the block bolts on the AC bracket (I dont have any longer wire). The car cranks fine and has 115-115 compression per rotor per face.
I think I need to either pull the motor, redo the grounds correctly and check ALL the body wiring, and then figure out what to do about the no spark.
Any input welcome, thanks guys, its becoming a headache.
01-23-05, 10:06 PM
#3
Ok I got under the car today (jeeze who says being sick means your lazy) and followed the ground wire.
The black with yellow stripe goes from the rear of tranny bellhousing to the strut tower. My 8guage wire runs from the strut tower to the battery. My 4guage goes from the ac bracket to the battery terminal.
Eh im going to start going through the FSM guidelines.
The black with yellow stripe goes from the rear of tranny bellhousing to the strut tower. My 8guage wire runs from the strut tower to the battery. My 4guage goes from the ac bracket to the battery terminal.
Eh im going to start going through the FSM guidelines.
01-26-05, 07:02 PM
#4
Completly stripped the wiring harness again.
Checked every guideline in the FSM, including checking for continuity with the CAS wiring to the ecu, checking every wire to the harness from its plug.
Tried all 3 ecu's after testing and nothing. Replaced ENGINE and METER fuses with brand new ones.
Is there any way I can check at the ecu if its getting power? Is it safe to put a test light on the 12v source from the battery for it??
What else should I try guys?
Checked every guideline in the FSM, including checking for continuity with the CAS wiring to the ecu, checking every wire to the harness from its plug.
Tried all 3 ecu's after testing and nothing. Replaced ENGINE and METER fuses with brand new ones.
Is there any way I can check at the ecu if its getting power? Is it safe to put a test light on the 12v source from the battery for it??
What else should I try guys?
01-26-05, 08:06 PM
#5
I R SAD PANDA W/O BAW
The tach gets its signal from the trailing coils so that may be part of what is going wrong. Did you check the resistances for the coils like it says in the FSM? Have you pulled the spark plug wires off and put them near the strut tower to see if they spark? Are you getting fuel? Does the engine turn over?
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01-26-05, 08:52 PM
#8
HAILERS
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HAILER'S NUMBER ONE CHECKOUT: Pull the cas out but leave its electrical connector connected. Put the LEAD coil wires near the left strut tower studs or any good ground.
Turn the key to ON. Now take the cas in hand and spin the lower gear rapidly. Question: Did the plugs spark. Should have. Write back for HAILER'S NUMBER TWO CHECKOUT.
Turn the key to ON. Now take the cas in hand and spin the lower gear rapidly. Question: Did the plugs spark. Should have. Write back for HAILER'S NUMBER TWO CHECKOUT.
01-26-05, 09:50 PM
#9
Hailers I have read through all 5-6 options in your previous posts and tried each one.
I have a very unique situation right now. The cas wiring harness side connector was badly damaged and I removed it and used just 4 crimp ends on it. Now I changed the cas plug end to 4 crimp ends too. After doing so, I could yank the cas, spin it, and hear the fuel injectors spray and have great spark. After nserting the cas into its proper location, I would get no spark. I tried my known good working cas from my car in it and it does the same damn thing.
Whats going on here?
I have a very unique situation right now. The cas wiring harness side connector was badly damaged and I removed it and used just 4 crimp ends on it. Now I changed the cas plug end to 4 crimp ends too. After doing so, I could yank the cas, spin it, and hear the fuel injectors spray and have great spark. After nserting the cas into its proper location, I would get no spark. I tried my known good working cas from my car in it and it does the same damn thing.
Whats going on here?
01-26-05, 11:12 PM
#10
It has to be a short. It has to be grounding out when I insert it into its front cover location. But where! Uggg..
*EDIT*
Heres a question...... The last mechanic who worked on this car at the ECU, uncovered the CAS wires and ran a ground to that sheilding, and any other sheilded wire, to the chasis of the car. Could this somehow ground out the signal?
Oh and the BAC valve is acting really weird. It ill start randomly clicking and not stop until I flip the key off or disconnect the battery.
*EDIT*
Heres a question...... The last mechanic who worked on this car at the ECU, uncovered the CAS wires and ran a ground to that sheilding, and any other sheilded wire, to the chasis of the car. Could this somehow ground out the signal?
Oh and the BAC valve is acting really weird. It ill start randomly clicking and not stop until I flip the key off or disconnect the battery.
01-26-05, 11:26 PM
#12
Its not even my car. I am working on it for a friend. It needs some work, but had over $2k in performance parts. The vehical was a 1991 NA origonally, looks like the last owner blew the motor, bought a rebuild kit, never did it, then droped in the JSPEC TII motor in its place.
01-27-05, 12:20 AM
#13
The Bridgy goes BRAP BRAP
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marc, you left before I could tell you that my dad said he'd has a problem like that before and that the grounding is bad, you need to check and recheck grounds and make sure nothing's wrong with that.
01-27-05, 08:48 AM
#15
The engine ground goes like this:
Black 4guage and 8guage wires.
4guauge goes to AC bracket.
8guauge goes to strut tower
Black with yellow stripe stock ground (whats left of it) runs from rear iron starter bolt like it should, to the same location as the 8guage.
I will move the 4 guage and re run the 8 guage to better spots and remove the extra ecu grounds and see what happens.
Black 4guage and 8guage wires.
4guauge goes to AC bracket.
8guauge goes to strut tower
Black with yellow stripe stock ground (whats left of it) runs from rear iron starter bolt like it should, to the same location as the 8guage.
I will move the 4 guage and re run the 8 guage to better spots and remove the extra ecu grounds and see what happens.
01-27-05, 09:36 AM
#16
HAILERS
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I don't see how it can be a grounding problem. You took a spare cas, held it in your hand with the connector connected. Turned the key to ON and spun the drive gear. It sparked. Now someone tell me the ground is not good.
Tell you what, do that very same thing again. It will probably cause the plugs to spark like it did before. THEN, hold the cas against a known ground, and do the same thing again to see if it still causes spark.
It sounds like one of your new connections to the cas is grounding/shorting out when you install the cas. But you implied that already. Sort of.
You might ring out the cas wires , wire by wire to the ECU plug to make sure they are not crossed up.
The lead coil has to be bolted to the frame for it to work. Just threw that in for FYI.
Tell you what, do that very same thing again. It will probably cause the plugs to spark like it did before. THEN, hold the cas against a known ground, and do the same thing again to see if it still causes spark.
It sounds like one of your new connections to the cas is grounding/shorting out when you install the cas. But you implied that already. Sort of.
You might ring out the cas wires , wire by wire to the ECU plug to make sure they are not crossed up.
The lead coil has to be bolted to the frame for it to work. Just threw that in for FYI.
01-27-05, 10:04 AM
#17
I did that last night.
I held the cas in its location, about 1" above so that the gears would not lock, spun it via the open top, and nothing. No spark. I will try again for the sake of it
.
I doublt checked the coil mounting a while ago. I will go double check all my wiring and then wrap in electrical tape just in case and report back.
I held the cas in its location, about 1" above so that the gears would not lock, spun it via the open top, and nothing. No spark. I will try again for the sake of it
. I doublt checked the coil mounting a while ago. I will go double check all my wiring and then wrap in electrical tape just in case and report back.
01-27-05, 03:30 PM
#18
Ok. Crap.
Well I decided I better re do the connections at the CAS, I did not trust the crimp ones I used anyways. So I soldered on a extra 4 pin connector to both sides, worked great, got spark every time I would spin it.
Soooo I put it back into its location and cranked it. No spark. I took it out, held it on the UIM and spun it, got spark. So I *ring*ed out the wires to the ecu and as soon as I touched the wiring harness nothing. I tried 2 other ecu's and nothing. Theres still a short somewhere I just cant find it. I have gone through nearly the entire harness. Theres no splits/craked casings even.
I noticed that if the cas is outside the stock location and that after inserting it and it wont spark, it will not spark until I disconnect and reconnect the battery.
Well I decided I better re do the connections at the CAS, I did not trust the crimp ones I used anyways. So I soldered on a extra 4 pin connector to both sides, worked great, got spark every time I would spin it.
Soooo I put it back into its location and cranked it. No spark. I took it out, held it on the UIM and spun it, got spark. So I *ring*ed out the wires to the ecu and as soon as I touched the wiring harness nothing. I tried 2 other ecu's and nothing. Theres still a short somewhere I just cant find it. I have gone through nearly the entire harness. Theres no splits/craked casings even.
I noticed that if the cas is outside the stock location and that after inserting it and it wont spark, it will not spark until I disconnect and reconnect the battery.
01-27-05, 05:19 PM
#19
The Bridgy goes BRAP BRAP
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hmm, are you gonna be working on it all day again? If you want any help or anything I can come over, or something, give me a call on the cell if you want me to come over.
01-27-05, 09:00 PM
#20
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Originally Posted by The Spyder
Ok. Crap.
Well I decided I better re do the connections at the CAS, I did not trust the crimp ones I used anyways. So I soldered on a extra 4 pin connector to both sides, worked great, got spark every time I would spin it.
Soooo I put it back into its location and cranked it. No spark. I took it out, held it on the UIM and spun it, got spark. So I *ring*ed out the wires to the ecu and as soon as I touched the wiring harness nothing. I tried 2 other ecu's and nothing. Theres still a short somewhere I just cant find it. I have gone through nearly the entire harness. Theres no splits/craked casings even.
I noticed that if the cas is outside the stock location and that after inserting it and it wont spark, it will not spark until I disconnect and reconnect the battery.
Well I decided I better re do the connections at the CAS, I did not trust the crimp ones I used anyways. So I soldered on a extra 4 pin connector to both sides, worked great, got spark every time I would spin it.
Soooo I put it back into its location and cranked it. No spark. I took it out, held it on the UIM and spun it, got spark. So I *ring*ed out the wires to the ecu and as soon as I touched the wiring harness nothing. I tried 2 other ecu's and nothing. Theres still a short somewhere I just cant find it. I have gone through nearly the entire harness. Theres no splits/craked casings even.
I noticed that if the cas is outside the stock location and that after inserting it and it wont spark, it will not spark until I disconnect and reconnect the battery.
i believe you said this was a jspec drop in.
01-28-05, 12:49 AM
#22
Man why does this wiring harness have to be soo screwed up at the ECU. I am not the best at reading wiring diagrams and things have been done and redone by about 4 people so I dont even know how its supposed to be.
Time for a new harness.
Time for a new harness.
01-28-05, 10:58 AM
#23
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Just disconnect the plug at the ECU and the plug at the cas, then get a meter and see if any of the wires is touching/reading to ground.
Or install the cas and its plug then go disconnect the plug at the ECU and see if any of the four wires read to ground.
Or install the cas and its plug then go disconnect the plug at the ECU and see if any of the four wires read to ground.
01-28-05, 01:37 PM
#25
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JPG attached. Pull the cas plug off. Pull the plug off the ECU, the one to the far right that has the most pins.
Put the meter on ohms. Put the negative lead on a known ground line one of the studs that hold the ECU in place.
Put the meter positve lead on pins N, P, T, Q one at a time please. Each time the meters reading should not show anything or the display should not change at all.
Then put the CAS plug back on and install the cas temporarily. Do the exact same thing as above with each pin. Same results. No change in the reading at all.
Double check the meter by putting the positive lead on another gound point on the chassis to make sure the meter is working and that the negative lead is indeed on a good ground. The meter should read under .5 ohms.
If there is no short to ground on either wire, then put the positive lead on pin N and the negative lead on pin P. You should read continuity and the meter should read approx .....heck I forgot, something like 200 ohms. I'm not going to look for the reading in the fsm. It's there in the fsm. My 200ohms figure might be wrong.
Then put the meters leads on pins T and Q just like above and you should get a reading very close to the reading when you read b/t N and P.
If both readings, are approx the same, and you saw no shorts to ground on either wire when you checked the four wires individually, there should not be a problem with the cas. But there must be a short , because you said (if I remember right), that you had spark when you had the cas in you hand and spun the gear on the bottom of the cas with the key to ON.
If you don't have a short on any of the four wires........nothing makes any sense.
Unless you take into account that when you spin the cas by hand with the key to ON, the starter is not in the picture and there is no DRAG on the battery pulling the voltage waaaay down. Maybe with the cas installed and the starter turning the engine over the voltage to the ignitor is much lower resulting in a spark but a spark that is anemic compared to the cas held in hand.
Put the meter on ohms. Put the negative lead on a known ground line one of the studs that hold the ECU in place.
Put the meter positve lead on pins N, P, T, Q one at a time please. Each time the meters reading should not show anything or the display should not change at all.
Then put the CAS plug back on and install the cas temporarily. Do the exact same thing as above with each pin. Same results. No change in the reading at all.
Double check the meter by putting the positive lead on another gound point on the chassis to make sure the meter is working and that the negative lead is indeed on a good ground. The meter should read under .5 ohms.
If there is no short to ground on either wire, then put the positive lead on pin N and the negative lead on pin P. You should read continuity and the meter should read approx .....heck I forgot, something like 200 ohms. I'm not going to look for the reading in the fsm. It's there in the fsm. My 200ohms figure might be wrong.
Then put the meters leads on pins T and Q just like above and you should get a reading very close to the reading when you read b/t N and P.
If both readings, are approx the same, and you saw no shorts to ground on either wire when you checked the four wires individually, there should not be a problem with the cas. But there must be a short , because you said (if I remember right), that you had spark when you had the cas in you hand and spun the gear on the bottom of the cas with the key to ON.
If you don't have a short on any of the four wires........nothing makes any sense.
Unless you take into account that when you spin the cas by hand with the key to ON, the starter is not in the picture and there is no DRAG on the battery pulling the voltage waaaay down. Maybe with the cas installed and the starter turning the engine over the voltage to the ignitor is much lower resulting in a spark but a spark that is anemic compared to the cas held in hand.