Installed new parts Coolant sensor Plugs (NGK Iridiums) Wires (MSD) Cap & Rotor (MSD) Coil. (MSD)
Now have no spark!!!!
Process so far Swapped out coil for another new one, and no change. Swapped out the whole distributor with all new parts *Cap rotor, pick up and ICM* NO CHANGE. Swapped out the wires for a set from another car that is working just fine. NO CHANGE, GRRR. Swapped all NEW fuses into the under dash fuse box. NO CHANGE.
ECM flashes code 12 in diagnostic mode so all good there. Tested all of the fuse-able links coming off the bulkhead connector I counted 5. And all five have power after the link (black box). With key in RUN I get 12V on the pink wire on the grey coil connector. I tested the Pick Up Coil on the installed Distributor and it is within the 500-1000 range (750ish) so all good there. TACH moves to around 300 rpm.
I unplugged plug wire #1 shoved a plug into it to check for spark, there is none.
Car turns over just fine.
Points to NOTE, it drove into my garage no problems. Someone at some point added a bunch of ground wires, meh I don't think that could be an issue? I removed the deck lid to get to the rear plugs. I blew a fuse cause the trunk light fell out and made contact. But note I changed all the fuses. The trunk light does not come on and neither does the foot well lights.
I have been trying to get this car started for over a week now. PLEASE HELP ME!
[This message has been edited by Inferno (edited 10-11-2014).]
Since the car started and had spark before you replaced the parts: one of the wires making the connection to the coil was disturbed. Check to see if power is getting to the coil
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Ok guys. Yesterday after unplugging then plugging some components, we suddenly had spark coming off the ignition coil.
I stopped right there and didnt touch ANYTHING!
I had to run to do some stuff yesterday (pick up a Fiero)
Go out today to start where I left off, I went and turned the ignition and now NO spark. NOTHING WAS TOUCHED from yesterday to today! WTF?!
So I installed a new coil, and ICM and still nothing. I tested the PUC and it come back with a steady .780 ohms resistance so it is in the 500 to 1500 range.
As you can see from my first post I have tried everything I can think of.
What changed between your car running and not running? Temperature. Your electronics are losing contact....maybe a broken wire or maybe a bad pin in a connector.
Still say that you have a bad connector or loose wire at the coil or module. Test the integrity/ continuity of the small wire harness that connects the Ign module to coil with an ohm meter. Should be at or near zero ohms for all wires. If that reads OK then check for 12v at the other connector with the ignition on but not in start position. If you have no spark that means that the coil is not being energized and or pulsed.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Powerlog manifold, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
As I stated, I have 12V constant with the ignition in run on the grey plug. I tested the wires from the ICM to the coil and I have continuity. I am going to swap a 4th coil in and see what I get.
I am a little fuzzy on how to test a coil though. The information in the Haynes manual is not too clear.
Is the cap pinching the pick up coil wire and shorting it out over time. Many of the replacement coils have leads on them that are too long and allow the wire to get pinched.
Yes over time the plastic insulation relaxes and ends up causing a short.
As I stated, I have 12V constant with the ignition in run on the grey plug. I tested the wires from the ICM to the coil and I have continuity. I am going to swap a 4th coil in and see what I get.
I am a little fuzzy on how to test a coil though. The information in the Haynes manual is not too clear.
Is the cap pinching the pick up coil wire and shorting it out over time. Many of the replacement coils have leads on them that are too long and allow the wire to get pinched.
Yes over time the plastic insulation relaxes and ends up causing a short.
Removed the ICM and tested the PUC. and got a 0.764 Ω
Installed a new out of the box ICM
Hooked up the plugs from the coil to ICM and to ECM
Turned the engine over with the cap off to check for rotation and for spark to the plug
Tested this way with two different plug wires and plugs.
I ALSO TESTED THE TWO WIRES FROM THE ICM TO THE COIL AND I HAVE CONTINUITY.
Then I tested the ground wire from the 4 pin connector at the ICM for ground continuity.
Looking at this from the Haynes manual I could be having a bad reference pulse to the ECM or a bad spark timing from the ECM to the ICM. In any case I have no Spark from the coil, I have 12V reference to the coil through the pink wire with the car in RUN.
[This message has been edited by Inferno (edited 10-16-2014).]
Test for spark coming directly out of the coil. If no spark but you have RPMs showing on the tach then replace the ignition coil.
If you have spark coming out of the coil but not out of the distributor, look for a cracked rotor.
Installed a coil from another Fiero that I drove and parked right in front of this one and I still have no spark, but I have a Tach reference that is giving me 300-400rpms.
Nice pictures and good info, but are you saying the plug tests came back no spark, the ground was good, and the pink wire good?
I don't like the look of the wires at the grey coil connector. That's exactly the kind of damage that seems likely to result in these problems. You have power to that point, but you might not have it at the coil where you need it. I always replace connectors like that. I would also replace the four wire connector to the ICM because it's missing the lock. Then cover and wrap the wires. Thirty years of heat is bound to make all those wires brittle. When you replace parts they're connected to they break. IMHO
The ICM is grounded through those 2 attachment screws, and I have been told they should not change from the stock fasteners. Yours are not the original screws. It may be a stupid thing, but it also may be part of the problem. Also, I agree about the pickup coil wires.....they have been pinched and are likely damaged.
The ICM is grounded through those 2 attachment screws, and I have been told they should not change from the stock fasteners. Yours are not the original screws. It may be a stupid thing, but it also may be part of the problem. Also, I agree about the pickup coil wires.....they have been pinched and are likely damaged.
No the PUC wires are fine. I tested them as I even put up a picture of the test and moved them to ensure I didnt loose my reading.
You are correct the screws are not factory and I have no idea when they were changed but the car drove into my garage with those screws and I am getting a ground from them as I tested that as well.
The ICM is grounded through those 2 attachment screws, and I have been told they should not change from the stock fasteners. Yours are not the original screws. It may be a stupid thing, but it also may be part of the problem.
I doubt that lack of those two original screws would contribute to any problem. You can see in my heat-sink installation thread HERE that I drilled bigger holes in the distributor base and used larger screws with no issues. Actually, the larger screws help to dissipate the heat (which is why I didn't shorten and "beautify" them). Looks weird (not that anyone can see them when the distributor is installed), but this distributor has been transferred between three Fieros so far, and the same ICM is still doing fine six years after the modification.
If you are testing it properly, you have a tach response, then the ICM has to be sending ignition pulses to the ignition coil. Assuming the spark plug wire is good and the spark plug is good, the ignition coil has to be bad.
Maybe it's marginal enough to work on the other Fiero but not this one.
I hate it when there are posts that suddenly stop on this site and don't give the solution to the problem. So I wont be one of those AZZHOLS.
1- ICM was indeed shot. Screws worked just fine and the PUC was fine. 2- Plugs were soaked with gas. I pulled the fuel pump fuse, removed all the plugs and let the cylinders dry up over the last two days. Cleaned up the plugs and reinstalled. 3- Ground to the Coil was bad. Repaired it and now all good. 4- Accel wires failed, I made custom wires and checked for resistance and they failed. So I made a custom set of MSD wires. Now all good. 5- Timing was off, so I set the timing and now it is perfect. 6- The two wire plug from the ICM to the coil was FUBAR and was giving intermittent connectivity. Replaced it with another one.
Like it says it was a bunch of little things that were going wrong with it. But I kept at it and looked at it logically and in the end it lives again. Hopefully the owner will come by tomorrow and pick it up and leave a very happy man. He is an older gentleman that just can not work on cars like he used to and as we all know these cars can be a bit difficult at times. I am sure he will be happy that I was able to help him out.
[This message has been edited by Inferno (edited 10-18-2014).]
