Need Help!! Ignition Problem Please Rx7 Gurus
05-11-05, 05:22 PM
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Need Help!! Ignition Problem Please Rx7 Gurus
HEY guys,
I am having a weird electrical problem with my S5. Its an S5 vert with a TII swap. I just put in the motor and went to start it but Im not getting any spark. I have checked for voltage at the coils but I am getting weird results. When both Coils are plugged in and bolted to the car I get only 1V. When just the Leading Coil is plugged in it does the same thing, only 1V. When just the trailing coil is plug in, I get about 6Vs. When both coils are unplugged I get 12V to the black/yellow wire. I have checked all my grounds, checked all fuses, tried 2 different ecus, tried another set of coils. But I still get the same result. ANYBODY help me please. HAILERS and Wayne88N/A please help me out GUYS. Thanks
I am having a weird electrical problem with my S5. Its an S5 vert with a TII swap. I just put in the motor and went to start it but Im not getting any spark. I have checked for voltage at the coils but I am getting weird results. When both Coils are plugged in and bolted to the car I get only 1V. When just the Leading Coil is plugged in it does the same thing, only 1V. When just the trailing coil is plug in, I get about 6Vs. When both coils are unplugged I get 12V to the black/yellow wire. I have checked all my grounds, checked all fuses, tried 2 different ecus, tried another set of coils. But I still get the same result. ANYBODY help me please. HAILERS and Wayne88N/A please help me out GUYS. Thanks
05-11-05, 05:46 PM
#3
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How exactly are you reading this voltage? Are you backprobing the connector while still connected, with the other meter lead to ground?
Thing is, if voltage drops on a circuit just because a plug's connected, then SOMETHING is dropping the voltage, much like a short would do. But if you're not blowing fuses, you don't have a short...
Pull the plug wires off of the coils, and do the voltage checks again. On the black/yellow wire, to ground. With the plug connected. Key on, but not cranking. Both coil packs. What do you get?
Thing is, if voltage drops on a circuit just because a plug's connected, then SOMETHING is dropping the voltage, much like a short would do. But if you're not blowing fuses, you don't have a short...
Pull the plug wires off of the coils, and do the voltage checks again. On the black/yellow wire, to ground. With the plug connected. Key on, but not cranking. Both coil packs. What do you get?
05-12-05, 12:57 AM
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yea I did backprobe the connector while it was plugged in.
When I unplug the connectors from both coils and check for voltage I get 12V. When I plug in both coils and check for voltage I get only 1V. I did this with the key on. Still nothing. I dont get it, I get voltage when they are unplugged but right when I plug in the coils I get nothing or 1V.
When I unplug the connectors from both coils and check for voltage I get 12V. When I plug in both coils and check for voltage I get only 1V. I did this with the key on. Still nothing. I dont get it, I get voltage when they are unplugged but right when I plug in the coils I get nothing or 1V.
05-12-05, 09:00 AM
#5
Former Moderator. RIP Icemark.
Originally Posted by fcDROPINthetop
yea I did backprobe the connector while it was plugged in.
When I unplug the connectors from both coils and check for voltage I get 12V. When I plug in both coils and check for voltage I get only 1V. I did this with the key on. Still nothing. I dont get it, I get voltage when they are unplugged but right when I plug in the coils I get nothing or 1V.
When I unplug the connectors from both coils and check for voltage I get 12V. When I plug in both coils and check for voltage I get only 1V. I did this with the key on. Still nothing. I dont get it, I get voltage when they are unplugged but right when I plug in the coils I get nothing or 1V.
This is with your meter's (-) neg/black lead on a good body ground, and the (+) positive of your meter on the black/yellow at the coil???
I am very skeptical.
05-12-05, 09:50 AM
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The only way that could be possible is if the coil is in a continuous fire mode, and is dropping the voltage. Kind of like the coil is shorted, but not a direct short to ground, i.e. you're not getting abnormal current flow...
Since the igniter controls the coil discharges, and since you've already replaced the coil (I think you said that in the PM, right?), look at the igniter next. A way to troubleshoot this possibly is to remove the wiring on the igniter connections itself, then check to see if you still have the funky voltage drop on the black/ yellow...
Since the igniter controls the coil discharges, and since you've already replaced the coil (I think you said that in the PM, right?), look at the igniter next. A way to troubleshoot this possibly is to remove the wiring on the igniter connections itself, then check to see if you still have the funky voltage drop on the black/ yellow...
05-12-05, 12:26 PM
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The igniter has 2 small 8mm nuts right wayne? I unbolted those and checked the voltage again and it was still the same.
Icemark, I did check the voltage correctly with the voltmeter. Black to ground, and red to the black/yellow wire of the coil.
Okay just for example and we are only gonna use just the Leading coil for now and leave the trailing coil unplugged. OK when I plug in the Leading coil and bolt it down to the car it reads only 1V. But when I unbolt the coil and pull it off the car and check for voltage I get about 6Vs. When I unplug the connector from the coil and check for voltage at the black/yellow wire I get 12V.
So I figured out that I am getting 12Vs to the black/yellow power wire that goes to the coil. But for some reason when I plug in the coils and/or bolt them down to the car, it loses voltage. Its like something is drawing the coil away or something
ANY ideas guys?
PLEASE HELP
Icemark, I did check the voltage correctly with the voltmeter. Black to ground, and red to the black/yellow wire of the coil.
Okay just for example and we are only gonna use just the Leading coil for now and leave the trailing coil unplugged. OK when I plug in the Leading coil and bolt it down to the car it reads only 1V. But when I unbolt the coil and pull it off the car and check for voltage I get about 6Vs. When I unplug the connector from the coil and check for voltage at the black/yellow wire I get 12V.
So I figured out that I am getting 12Vs to the black/yellow power wire that goes to the coil. But for some reason when I plug in the coils and/or bolt them down to the car, it loses voltage. Its like something is drawing the coil away or something
ANY ideas guys?
PLEASE HELP
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05-12-05, 02:58 PM
#8
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There's quicker ways to check a coil/ignitor. Remove the cas. Leave its elec plug on., Turn the key to ON. Rotate the cas lower gear with one of the LEAD coil wires just resting in the top of the bore. If the coil/ignitor is good you'll see and hear a very large spark.
This eliminates any voltage drop by the starter circuit. It's a ten minute bullet proof way of determining if the coil assy is any good or not.
I've even left one of the lead coil wires all the way out of the bore and a spark will jump from the coil bore to the nearest ground.
This eliminates any voltage drop by the starter circuit. It's a ten minute bullet proof way of determining if the coil assy is any good or not.
I've even left one of the lead coil wires all the way out of the bore and a spark will jump from the coil bore to the nearest ground.
05-12-05, 04:17 PM
#9
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Yeah, do what Hailers said first, just in case you actually DO have spark but think you don't. I'm beginning to wonder if what you are seeing as far as voltages are normal, because once power is applied to the coil it will "charge", which probably will drop the system voltage due to the magnetic inductance now in the circuit (basically, resistance caused by the magnetic field in the coil). It will not discharge until the igniter signals it to, which is how the spark is produced (field collapse)...
Then again, I don't know how much stock to put in my theory. Hailers likes to play with his car, maybe he can perform the exact tests you are and get back with us
You've already changed the leading coil assy, right?
Then again, I don't know how much stock to put in my theory. Hailers likes to play with his car, maybe he can perform the exact tests you are and get back with us
You've already changed the leading coil assy, right?
05-12-05, 06:56 PM
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hailers,
I tried rotating the cas once already, and it did nothing, No spark. But I will try it again just to verify. I am really getting confused about all this electrical stuff. I am pretty sure the coils are good.
Wayne,
yea I actually changed both coils assy with 2 working one from my friends car, got the same result.
what else can be wrong? Hailers, Wayne?
I tried rotating the cas once already, and it did nothing, No spark. But I will try it again just to verify. I am really getting confused about all this electrical stuff. I am pretty sure the coils are good.
Wayne,
yea I actually changed both coils assy with 2 working one from my friends car, got the same result.
what else can be wrong? Hailers, Wayne?
05-12-05, 07:25 PM
#11
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Doesn't make any sense, then- if you had a bad coil (or igniter) that caused the voltage drop, a known good one should have fixed it.
Tell ya what- find the capacitor for the ignition circuit (little black box bolted to the chassis under the trailing coil pack), remove the bolt and cap and keep the cap away from the chassis metal. Now try everything again, see if you get spark and/or good voltage...
Tell ya what- find the capacitor for the ignition circuit (little black box bolted to the chassis under the trailing coil pack), remove the bolt and cap and keep the cap away from the chassis metal. Now try everything again, see if you get spark and/or good voltage...
05-12-05, 07:29 PM
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Just in case: All electrical plugs must be connected for the following, AND the engine does NOT get turned over in anyway.
Pull the CAS out of its bore in the engnine. Reconnect the cas's electrical plug. Turn the key to ON. Spin the cas lower gear with one of the LEAD coil wires just out of the bore OR if you want just lay the sparkplug end of the wire on the fender near one of the strut tower nuts.
You should see spark easily. If you don't, then the connector at the ECU is off or one of the wires from the cas to the ECU is busted (won't happen, very rare, ain't gonna be this).
Remember, all the plugs should be on the cas, coil assy, ECU .
EVEN IF you see no spark, let me ask you this. When you spin the cas gear, do you hear the clicking of the fuel injectors.. I can and you should also.
If you don't hear the injectors or see spark from the sparkplug wire, then there's one other test.
Key to ON. Remove the pressure/boost sensor connector. Meter negative lead on a chassis ground. Positive lead on the BROWN/WHITE wire in the plug. You should see 5 volts dc. If not, write back and I'll tell you the sad news. I'm not telling anyone the pressure sensor has squat to do with spark. What your looking for is the ECU's 5vdc output which goes to various sensors. This just happens to be the easiest place to look for it. If you have no 5vdc with the key to ON, then the ECU is internally busted or a plug is off the ECU, and maybe a fuse blow but not likely. The ECU will not ever, never make spark unless the ECU is capable of producing the 5vdc
Pull the CAS out of its bore in the engnine. Reconnect the cas's electrical plug. Turn the key to ON. Spin the cas lower gear with one of the LEAD coil wires just out of the bore OR if you want just lay the sparkplug end of the wire on the fender near one of the strut tower nuts.
You should see spark easily. If you don't, then the connector at the ECU is off or one of the wires from the cas to the ECU is busted (won't happen, very rare, ain't gonna be this).
Remember, all the plugs should be on the cas, coil assy, ECU .
EVEN IF you see no spark, let me ask you this. When you spin the cas gear, do you hear the clicking of the fuel injectors.. I can and you should also.
If you don't hear the injectors or see spark from the sparkplug wire, then there's one other test.
Key to ON. Remove the pressure/boost sensor connector. Meter negative lead on a chassis ground. Positive lead on the BROWN/WHITE wire in the plug. You should see 5 volts dc. If not, write back and I'll tell you the sad news. I'm not telling anyone the pressure sensor has squat to do with spark. What your looking for is the ECU's 5vdc output which goes to various sensors. This just happens to be the easiest place to look for it. If you have no 5vdc with the key to ON, then the ECU is internally busted or a plug is off the ECU, and maybe a fuse blow but not likely. The ECU will not ever, never make spark unless the ECU is capable of producing the 5vdc
05-12-05, 07:29 PM
#13
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Just in case: All electrical plugs must be connected for the following, AND the engine does NOT get turned over in anyway.
Pull the CAS out of its bore in the engnine. Reconnect the cas's electrical plug. Turn the key to ON. Spin the cas lower gear with one of the LEAD coil wires just out of the bore OR if you want just lay the sparkplug end of the wire on the fender near one of the strut tower nuts.
You should see spark easily. If you don't, then the connector at the ECU is off or one of the wires from the cas to the ECU is busted (won't happen, very rare, ain't gonna be this).
Remember, all the plugs should be on the cas, coil assy, ECU .
EVEN IF you see no spark, let me ask you this. When you spin the cas gear, do you hear the clicking of the fuel injectors.. I can and you should also.
If you don't hear the injectors or see spark from the sparkplug wire, then there's one other test.
Key to ON. Remove the pressure/boost sensor connector. Meter negative lead on a chassis ground. Positive lead on the BROWN/WHITE wire in the plug. You should see 5 volts dc. If not, write back and I'll tell you the sad news. I'm not telling anyone the pressure sensor has squat to do with spark. What your looking for is the ECU's 5vdc output which goes to various sensors. This just happens to be the easiest place to look for it. If you have no 5vdc with the key to ON, then the ECU is internally busted or a plug is off the ECU, and maybe a fuse blow but not likely. The ECU will not ever, never make spark unless the ECU is capable of producing the 5vdc reference voltage.
Pull the CAS out of its bore in the engnine. Reconnect the cas's electrical plug. Turn the key to ON. Spin the cas lower gear with one of the LEAD coil wires just out of the bore OR if you want just lay the sparkplug end of the wire on the fender near one of the strut tower nuts.
You should see spark easily. If you don't, then the connector at the ECU is off or one of the wires from the cas to the ECU is busted (won't happen, very rare, ain't gonna be this).
Remember, all the plugs should be on the cas, coil assy, ECU .
EVEN IF you see no spark, let me ask you this. When you spin the cas gear, do you hear the clicking of the fuel injectors.. I can and you should also.
If you don't hear the injectors or see spark from the sparkplug wire, then there's one other test.
Key to ON. Remove the pressure/boost sensor connector. Meter negative lead on a chassis ground. Positive lead on the BROWN/WHITE wire in the plug. You should see 5 volts dc. If not, write back and I'll tell you the sad news. I'm not telling anyone the pressure sensor has squat to do with spark. What your looking for is the ECU's 5vdc output which goes to various sensors. This just happens to be the easiest place to look for it. If you have no 5vdc with the key to ON, then the ECU is internally busted or a plug is off the ECU, and maybe a fuse blow but not likely. The ECU will not ever, never make spark unless the ECU is capable of producing the 5vdc reference voltage.
05-12-05, 08:15 PM
#14
I R SAD PANDA W/O BAW
I've been helping him troubleshoot the car and have no idea what the problem is. I have tested for the 5v at the brown/white wire on the pressure sensor (read it one of your posts through a search 
). I was not there to see if he heard the injectors clicking when the CAS was spun. He's already described everything else. Checked all the fuses in the cabin and in the engine bay. The resistance on both the coils is 0 ohms (FSM states below 1 is in spec).
It's strange that he has swapped known good coils, ECUs, and CAS's without a cure already.
). I was not there to see if he heard the injectors clicking when the CAS was spun. He's already described everything else. Checked all the fuses in the cabin and in the engine bay. The resistance on both the coils is 0 ohms (FSM states below 1 is in spec).It's strange that he has swapped known good coils, ECUs, and CAS's without a cure already.
05-13-05, 12:29 AM
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ok wayne I will look for that black box, ignition circuit and try that. Hailers i will try the cas test again to see if the injectors click. Do all the injectors click or just the primaries?
Thanks again,
Dominic
Thanks again,
Dominic
05-13-05, 07:19 AM
#17
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Maybe he forgot to connect the ground for the ecu, it should be bolted to the block... 2 black wires with a ring connector.. it seems that everyone doing the tII swap is leaving this wire unconnected..
05-13-05, 10:13 AM
#18
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Originally Posted by HAILERS
Only the primarys unless you can simulate over thirty five hunderd rpm with your fingers.
05-13-05, 01:15 PM
#19
I R SAD PANDA W/O BAW
Originally Posted by MARTIN
Maybe he forgot to connect the ground for the ecu, it should be bolted to the block... 2 black wires with a ring connector.. it seems that everyone doing the tII swap is leaving this wire unconnected..
Originally Posted by WAYNE88N/A
Which means you'd have to spin the CAS about 1750 rpm. Or about 30 times per second. It's doable- drink a lot of coffee first
We'll most likely be troubleshooting it again tonight so any suggestions would be welcome.
05-13-05, 01:46 PM
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HAHA, I dont think I will spin that CAS that fast wayne... I would probably have to be on crack to do that.... hopefully we can figure it out tonight though just double-check those things you guys told me to....
Thanks guys for all your input.
this is what the car looks like right now(well minus all the other stuff on the engine that we put on like the wiring, afm, etc...) check out the pics:
Thanks guys for all your input.
this is what the car looks like right now(well minus all the other stuff on the engine that we put on like the wiring, afm, etc...) check out the pics:
Last edited by fcDROPINthetop; 05-13-05 at 01:50 PM.
05-13-05, 11:46 PM
#22
I R SAD PANDA W/O BAW
He's using s5 turbo engine harness and s5 vert body harness. I'm here right now and we're trouble shooting.
When we spin the CAS the injectors do not click but the fuel pump activates like it would if you jumpered it at the yellow connector. Tried a different CAS same result. Different ECU same result.
So what does it mean if the injectors dont click but the fuel pump activates for a few seconds?
When we spin the CAS the injectors do not click but the fuel pump activates like it would if you jumpered it at the yellow connector. Tried a different CAS same result. Different ECU same result.
So what does it mean if the injectors dont click but the fuel pump activates for a few seconds?
05-14-05, 12:55 AM
#23
I R SAD PANDA W/O BAW
Pulled off the UIM and tested the voltage at the injectors. Under 5 volts for both the primaries. Also check voltage at the ECU connector and it was the same. Applied 12v to the actual injectors to confirm they arent dead and they test good and clicked. Still stumped.
Why would the injectors not be getting enough voltage? Is this maybe why we dont hear them clicking when we spin the CAS?
Why would the injectors not be getting enough voltage? Is this maybe why we dont hear them clicking when we spin the CAS?
05-14-05, 08:42 AM
#24
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You've got some type harness problem. Are you sure you don't have a series four emissions harness instead of a series five??????????????????????????????? Emissions harness is the one that goes to the fuel injectors, afm etc and runs along the right side of the engine bay to the ECU.
As you know, the fuel injectors get fed from the Main Relay thru the emissions harness on a black/yellow wire. You said you have no 12v on the black/yellow wire at the fuel injectors plugs.
I know what I'd do. I'd go to the ECU and pull the plug off and see if I had 12v at pins 1B and 1A. The 1B is the feed from the MAIN RELAY.
For some reason your not getting power from the MAIN RELAY. It feeds the small, two socket, white plug for the coils AND to the fuel injectors (black/yellow wire), plus the ECU pin 1B. The 1A is power from another wire and is battery voltage to the ECU.
I don't have a series five wiring diagram and this is about as far as I can go without one. I just know you need 12v to the black/yellow wire at the injectors and 12v to pin 1B for things to work. I'd suggest a harness plug is off maybe.
Pin 1A on the ECU is the most far right and top pin. Pull that plug off and turn the key to ON and see if there is 12v on the harness electrical plug. OOOOps, check pin 1B just under pin 1A. That is the important wire that feeds the ECU.
As you know, the fuel injectors get fed from the Main Relay thru the emissions harness on a black/yellow wire. You said you have no 12v on the black/yellow wire at the fuel injectors plugs.
I know what I'd do. I'd go to the ECU and pull the plug off and see if I had 12v at pins 1B and 1A. The 1B is the feed from the MAIN RELAY.
For some reason your not getting power from the MAIN RELAY. It feeds the small, two socket, white plug for the coils AND to the fuel injectors (black/yellow wire), plus the ECU pin 1B. The 1A is power from another wire and is battery voltage to the ECU.
I don't have a series five wiring diagram and this is about as far as I can go without one. I just know you need 12v to the black/yellow wire at the injectors and 12v to pin 1B for things to work. I'd suggest a harness plug is off maybe.
Pin 1A on the ECU is the most far right and top pin. Pull that plug off and turn the key to ON and see if there is 12v on the harness electrical plug. OOOOps, check pin 1B just under pin 1A. That is the important wire that feeds the ECU.
Last edited by HAILERS; 05-14-05 at 08:53 AM.
05-14-05, 11:45 AM
#25
I R SAD PANDA W/O BAW
Will check that out.
We are 99% sure it is an s5 turbo harness. It has the wiring for the electric OMP, knock sensor, and stock boost solenoid.
Should note that everything was removed off of the car for paint, except the dash harness. It's an s4 block with everything else s5. Not that I think that makes a difference.
We are 99% sure it is an s5 turbo harness. It has the wiring for the electric OMP, knock sensor, and stock boost solenoid.
Should note that everything was removed off of the car for paint, except the dash harness. It's an s4 block with everything else s5. Not that I think that makes a difference.