LT1 is being GAY
Typically when ever it doesn't start when it's rainy/damp it would point to the wires. Also check you fuel pressure reg. I've seen them act up and stop on occasion. Pull the vac line off of the reg and see if either fuel comes out or the line has a strong fuel odor from it. After the car has been running is usually when it leaks the most. THe heat soak in the inj rail builds excess pressure and causes it to leak. If both the wires and regulator have been changed, I would go to the opti next.
Paul
Paul
ok i just talk to the guy...its needs ingntion coil, new wires, spark plugs and a fuel filter!! so what kind of wires and plugs should i get??? witch ones are good.......i hav on there now MSD wires but i dont know what kind of spark plugs are in there now...........how much is this going to cost???
Joined: Nov 2001
Posts: 10,023
Likes: 6
From: LT1 land...the "409" of the 90s!
that is all good but did he actually find the problem or is he just taking the shot gun approch?
I would check the opti connections. the one on top is notorius for corroding
I would check the opti connections. the one on top is notorius for corroding
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Verdad Gallardo i trust him....i new it needed a really good tune for a while...+ hes good at what he does never had a problem with him b4 (knock on wood)lol....he also said that the coil was an artermarket one and that it was junk to start out with!!!!!
TECH Resident
Joined: Oct 2005
Posts: 812
Likes: 0
hey man had the same exact problem but took everyones word for it and got a new opti and that wasent the problem it ended up being the icm heres the steps I USED TO FIND THE PROBLEM
The first thing we will do is verify the optical sensor is working correctly. And here is how..
Unhook 1 fuel injector connector. With your test light check for pulsing ground on the NON PINK wire while cranking the engine (different years use different color wires but all year have pink wires for the positive voltage side of the connectors) The other choice you have is to use the noid light (noid light AZ OEM part number 25143), plug the noid light into the connector and crank the car. The light should flash..
Do you have a flashing ground while cranking?
Yes, the optical sensor is sending the signal and should be ok, continue to test the ignition system.
No, the optical sensor is not working see testing opti section.
Next we will see if the coil and ICM are causing the no spark.
First on the ICM connector with KOEO check for hot (93-95) on the Pink/Black and white/black wires or (96-97) on the Pink and Dark green wires. Do you have hot?
Yes, next step
No, (93-95) Check for hot at the pink wire a the ign coil. If you have power at the coil, but not at the ICM, The coil is shorted and preventing power from reaching the ICM. Replace the coil and retest. If you do not have hot at the coils pink wire, check the 10 amp Ign fuse. Repair as needed and retest.
(96-97) If you are missing hot on both wires at the module, check the 10amp ign fuse, Repair and retest. If you are missing hot only on the dark green wire, but not he pink wire, the coil has shorted and is preventing the voltage from reaching the module and must be replaced.
Next check for ground on the black wire. do you have ground?
Yes, next step
no, repair ground
next test for a pulsing ground at the dark green wire(96-97) or the White/black wire (93-95) at the coil coming from the ICM. Do you have a pulsing ground?
Yes, next step
No Replace the ICM *note, I have seen a bad coil burn up an ICM. It might be a good time to replace or upgrade your coil*
next with your test light check for hot on the Pink wire at the coil. do you have hot?
Yes, Replace your coil *note, High resistance from bad plug wires can burn out coils. You can Ohm test plug wires or replace them if wanted*
No, Check and repair ign fuse and retest
OPTI testing
If you failed the injector pulse test we must make sure that all the power is getting to the opti.
With the test light and the car on KOEO, unplug the opti connector at the optispark and test for hot at the red wire at the opti. do you have hot?
If yes. Next step
if no, the pos feed comes from the computer. Check that the PCM is sending the signal, if not then you might have a faulty PCM
Next, using a multi meter on volts scale, test the red/black and purple/white wires for 5 volts. Do you have 5 Volts?
Yes, next step
No, The 5 volt reference is provided by the PCM, possible PCM failure or PCM power feed problem
Next, test the pink/black wire for ground. Do you have ground?
Yes, then the optical sensor is not working and is probably bad. based on the other tests run this is causing your no spark condition. It’s time to replace your opti. You can also check for corrosion or damage to the opti connector and replace as needed.
No, the ground is provided by the PCM, possible PCM failure or PCM power feed problem.
Google FTW.
__________________
Pete - '94 Formula
Driver only carries $20 worth of ammunition !
The first thing we will do is verify the optical sensor is working correctly. And here is how..
Unhook 1 fuel injector connector. With your test light check for pulsing ground on the NON PINK wire while cranking the engine (different years use different color wires but all year have pink wires for the positive voltage side of the connectors) The other choice you have is to use the noid light (noid light AZ OEM part number 25143), plug the noid light into the connector and crank the car. The light should flash..
Do you have a flashing ground while cranking?
Yes, the optical sensor is sending the signal and should be ok, continue to test the ignition system.
No, the optical sensor is not working see testing opti section.
Next we will see if the coil and ICM are causing the no spark.
First on the ICM connector with KOEO check for hot (93-95) on the Pink/Black and white/black wires or (96-97) on the Pink and Dark green wires. Do you have hot?
Yes, next step
No, (93-95) Check for hot at the pink wire a the ign coil. If you have power at the coil, but not at the ICM, The coil is shorted and preventing power from reaching the ICM. Replace the coil and retest. If you do not have hot at the coils pink wire, check the 10 amp Ign fuse. Repair as needed and retest.
(96-97) If you are missing hot on both wires at the module, check the 10amp ign fuse, Repair and retest. If you are missing hot only on the dark green wire, but not he pink wire, the coil has shorted and is preventing the voltage from reaching the module and must be replaced.
Next check for ground on the black wire. do you have ground?
Yes, next step
no, repair ground
next test for a pulsing ground at the dark green wire(96-97) or the White/black wire (93-95) at the coil coming from the ICM. Do you have a pulsing ground?
Yes, next step
No Replace the ICM *note, I have seen a bad coil burn up an ICM. It might be a good time to replace or upgrade your coil*
next with your test light check for hot on the Pink wire at the coil. do you have hot?
Yes, Replace your coil *note, High resistance from bad plug wires can burn out coils. You can Ohm test plug wires or replace them if wanted*
No, Check and repair ign fuse and retest
OPTI testing
If you failed the injector pulse test we must make sure that all the power is getting to the opti.
With the test light and the car on KOEO, unplug the opti connector at the optispark and test for hot at the red wire at the opti. do you have hot?
If yes. Next step
if no, the pos feed comes from the computer. Check that the PCM is sending the signal, if not then you might have a faulty PCM
Next, using a multi meter on volts scale, test the red/black and purple/white wires for 5 volts. Do you have 5 Volts?
Yes, next step
No, The 5 volt reference is provided by the PCM, possible PCM failure or PCM power feed problem
Next, test the pink/black wire for ground. Do you have ground?
Yes, then the optical sensor is not working and is probably bad. based on the other tests run this is causing your no spark condition. It’s time to replace your opti. You can also check for corrosion or damage to the opti connector and replace as needed.
No, the ground is provided by the PCM, possible PCM failure or PCM power feed problem.
Google FTW.
__________________
Pete - '94 Formula
Driver only carries $20 worth of ammunition !
Originally Posted by skatinjay27
hey man had the same exact problem but took everyones word for it and got a new opti and that wasent the problem it ended up being the icm heres the steps I USED TO FIND THE PROBLEM
The first thing we will do is verify the optical sensor is working correctly. And here is how..
Unhook 1 fuel injector connector. With your test light check for pulsing ground on the NON PINK wire while cranking the engine (different years use different color wires but all year have pink wires for the positive voltage side of the connectors) The other choice you have is to use the noid light (noid light AZ OEM part number 25143), plug the noid light into the connector and crank the car. The light should flash..
Do you have a flashing ground while cranking?
Yes, the optical sensor is sending the signal and should be ok, continue to test the ignition system.
No, the optical sensor is not working see testing opti section.
Next we will see if the coil and ICM are causing the no spark.
First on the ICM connector with KOEO check for hot (93-95) on the Pink/Black and white/black wires or (96-97) on the Pink and Dark green wires. Do you have hot?
Yes, next step
No, (93-95) Check for hot at the pink wire a the ign coil. If you have power at the coil, but not at the ICM, The coil is shorted and preventing power from reaching the ICM. Replace the coil and retest. If you do not have hot at the coils pink wire, check the 10 amp Ign fuse. Repair as needed and retest.
(96-97) If you are missing hot on both wires at the module, check the 10amp ign fuse, Repair and retest. If you are missing hot only on the dark green wire, but not he pink wire, the coil has shorted and is preventing the voltage from reaching the module and must be replaced.
Next check for ground on the black wire. do you have ground?
Yes, next step
no, repair ground
next test for a pulsing ground at the dark green wire(96-97) or the White/black wire (93-95) at the coil coming from the ICM. Do you have a pulsing ground?
Yes, next step
No Replace the ICM *note, I have seen a bad coil burn up an ICM. It might be a good time to replace or upgrade your coil*
next with your test light check for hot on the Pink wire at the coil. do you have hot?
Yes, Replace your coil *note, High resistance from bad plug wires can burn out coils. You can Ohm test plug wires or replace them if wanted*
No, Check and repair ign fuse and retest
OPTI testing
If you failed the injector pulse test we must make sure that all the power is getting to the opti.
With the test light and the car on KOEO, unplug the opti connector at the optispark and test for hot at the red wire at the opti. do you have hot?
If yes. Next step
if no, the pos feed comes from the computer. Check that the PCM is sending the signal, if not then you might have a faulty PCM
Next, using a multi meter on volts scale, test the red/black and purple/white wires for 5 volts. Do you have 5 Volts?
Yes, next step
No, The 5 volt reference is provided by the PCM, possible PCM failure or PCM power feed problem
Next, test the pink/black wire for ground. Do you have ground?
Yes, then the optical sensor is not working and is probably bad. based on the other tests run this is causing your no spark condition. It’s time to replace your opti. You can also check for corrosion or damage to the opti connector and replace as needed.
No, the ground is provided by the PCM, possible PCM failure or PCM power feed problem.
Google FTW.
__________________
Pete - '94 Formula
Driver only carries $20 worth of ammunition !
The first thing we will do is verify the optical sensor is working correctly. And here is how..
Unhook 1 fuel injector connector. With your test light check for pulsing ground on the NON PINK wire while cranking the engine (different years use different color wires but all year have pink wires for the positive voltage side of the connectors) The other choice you have is to use the noid light (noid light AZ OEM part number 25143), plug the noid light into the connector and crank the car. The light should flash..
Do you have a flashing ground while cranking?
Yes, the optical sensor is sending the signal and should be ok, continue to test the ignition system.
No, the optical sensor is not working see testing opti section.
Next we will see if the coil and ICM are causing the no spark.
First on the ICM connector with KOEO check for hot (93-95) on the Pink/Black and white/black wires or (96-97) on the Pink and Dark green wires. Do you have hot?
Yes, next step
No, (93-95) Check for hot at the pink wire a the ign coil. If you have power at the coil, but not at the ICM, The coil is shorted and preventing power from reaching the ICM. Replace the coil and retest. If you do not have hot at the coils pink wire, check the 10 amp Ign fuse. Repair as needed and retest.
(96-97) If you are missing hot on both wires at the module, check the 10amp ign fuse, Repair and retest. If you are missing hot only on the dark green wire, but not he pink wire, the coil has shorted and is preventing the voltage from reaching the module and must be replaced.
Next check for ground on the black wire. do you have ground?
Yes, next step
no, repair ground
next test for a pulsing ground at the dark green wire(96-97) or the White/black wire (93-95) at the coil coming from the ICM. Do you have a pulsing ground?
Yes, next step
No Replace the ICM *note, I have seen a bad coil burn up an ICM. It might be a good time to replace or upgrade your coil*
next with your test light check for hot on the Pink wire at the coil. do you have hot?
Yes, Replace your coil *note, High resistance from bad plug wires can burn out coils. You can Ohm test plug wires or replace them if wanted*
No, Check and repair ign fuse and retest
OPTI testing
If you failed the injector pulse test we must make sure that all the power is getting to the opti.
With the test light and the car on KOEO, unplug the opti connector at the optispark and test for hot at the red wire at the opti. do you have hot?
If yes. Next step
if no, the pos feed comes from the computer. Check that the PCM is sending the signal, if not then you might have a faulty PCM
Next, using a multi meter on volts scale, test the red/black and purple/white wires for 5 volts. Do you have 5 Volts?
Yes, next step
No, The 5 volt reference is provided by the PCM, possible PCM failure or PCM power feed problem
Next, test the pink/black wire for ground. Do you have ground?
Yes, then the optical sensor is not working and is probably bad. based on the other tests run this is causing your no spark condition. It’s time to replace your opti. You can also check for corrosion or damage to the opti connector and replace as needed.
No, the ground is provided by the PCM, possible PCM failure or PCM power feed problem.
Google FTW.
__________________
Pete - '94 Formula
Driver only carries $20 worth of ammunition !
O.k, I had similar problems when it rained and I hated driving it when the rain came pouring down. It was my mass air flow sensor. I kept getting water into it and couldn't start it anymore. What I had to do was remove the Air filter and And dry it out.I kept trying to turn it on but the filter was still wet so when i cranked it over it was pulling in water from the filter. It may have damaged your mafs. I also had the strong fuel odor you were talking about. I'm not sure if it will apply to your car but this is just my input.
Banned
Joined: Apr 2008
Posts: 55
Likes: 0
From: DFW, Texas
hey man had the same exact problem but took everyones word for it and got a new opti and that wasent the problem it ended up being the icm heres the steps I USED TO FIND THE PROBLEM
The first thing we will do is verify the optical sensor is working correctly. And here is how..
Unhook 1 fuel injector connector. With your test light check for pulsing ground on the NON PINK wire while cranking the engine (different years use different color wires but all year have pink wires for the positive voltage side of the connectors) The other choice you have is to use the noid light (noid light AZ OEM part number 25143), plug the noid light into the connector and crank the car. The light should flash..
Do you have a flashing ground while cranking?
Yes, the optical sensor is sending the signal and should be ok, continue to test the ignition system.
No, the optical sensor is not working see testing opti section.
Next we will see if the coil and ICM are causing the no spark.
First on the ICM connector with KOEO check for hot (93-95) on the Pink/Black and white/black wires or (96-97) on the Pink and Dark green wires. Do you have hot?
Yes, next step
No, (93-95) Check for hot at the pink wire a the ign coil. If you have power at the coil, but not at the ICM, The coil is shorted and preventing power from reaching the ICM. Replace the coil and retest. If you do not have hot at the coils pink wire, check the 10 amp Ign fuse. Repair as needed and retest.
(96-97) If you are missing hot on both wires at the module, check the 10amp ign fuse, Repair and retest. If you are missing hot only on the dark green wire, but not he pink wire, the coil has shorted and is preventing the voltage from reaching the module and must be replaced.
Next check for ground on the black wire. do you have ground?
Yes, next step
no, repair ground
next test for a pulsing ground at the dark green wire(96-97) or the White/black wire (93-95) at the coil coming from the ICM. Do you have a pulsing ground?
Yes, next step
No Replace the ICM *note, I have seen a bad coil burn up an ICM. It might be a good time to replace or upgrade your coil*
next with your test light check for hot on the Pink wire at the coil. do you have hot?
Yes, Replace your coil *note, High resistance from bad plug wires can burn out coils. You can Ohm test plug wires or replace them if wanted*
No, Check and repair ign fuse and retest
OPTI testing
If you failed the injector pulse test we must make sure that all the power is getting to the opti.
With the test light and the car on KOEO, unplug the opti connector at the optispark and test for hot at the red wire at the opti. do you have hot?
If yes. Next step
if no, the pos feed comes from the computer. Check that the PCM is sending the signal, if not then you might have a faulty PCM
Next, using a multi meter on volts scale, test the red/black and purple/white wires for 5 volts. Do you have 5 Volts?
Yes, next step
No, The 5 volt reference is provided by the PCM, possible PCM failure or PCM power feed problem
Next, test the pink/black wire for ground. Do you have ground?
Yes, then the optical sensor is not working and is probably bad. based on the other tests run this is causing your no spark condition. It’s time to replace your opti. You can also check for corrosion or damage to the opti connector and replace as needed.
No, the ground is provided by the PCM, possible PCM failure or PCM power feed problem.
Google dumdumdum.
__________________
Pete - '94 Formula
Driver only carries $20 worth of ammunition !
The first thing we will do is verify the optical sensor is working correctly. And here is how..
Unhook 1 fuel injector connector. With your test light check for pulsing ground on the NON PINK wire while cranking the engine (different years use different color wires but all year have pink wires for the positive voltage side of the connectors) The other choice you have is to use the noid light (noid light AZ OEM part number 25143), plug the noid light into the connector and crank the car. The light should flash..
Do you have a flashing ground while cranking?
Yes, the optical sensor is sending the signal and should be ok, continue to test the ignition system.
No, the optical sensor is not working see testing opti section.
Next we will see if the coil and ICM are causing the no spark.
First on the ICM connector with KOEO check for hot (93-95) on the Pink/Black and white/black wires or (96-97) on the Pink and Dark green wires. Do you have hot?
Yes, next step
No, (93-95) Check for hot at the pink wire a the ign coil. If you have power at the coil, but not at the ICM, The coil is shorted and preventing power from reaching the ICM. Replace the coil and retest. If you do not have hot at the coils pink wire, check the 10 amp Ign fuse. Repair as needed and retest.
(96-97) If you are missing hot on both wires at the module, check the 10amp ign fuse, Repair and retest. If you are missing hot only on the dark green wire, but not he pink wire, the coil has shorted and is preventing the voltage from reaching the module and must be replaced.
Next check for ground on the black wire. do you have ground?
Yes, next step
no, repair ground
next test for a pulsing ground at the dark green wire(96-97) or the White/black wire (93-95) at the coil coming from the ICM. Do you have a pulsing ground?
Yes, next step
No Replace the ICM *note, I have seen a bad coil burn up an ICM. It might be a good time to replace or upgrade your coil*
next with your test light check for hot on the Pink wire at the coil. do you have hot?
Yes, Replace your coil *note, High resistance from bad plug wires can burn out coils. You can Ohm test plug wires or replace them if wanted*
No, Check and repair ign fuse and retest
OPTI testing
If you failed the injector pulse test we must make sure that all the power is getting to the opti.
With the test light and the car on KOEO, unplug the opti connector at the optispark and test for hot at the red wire at the opti. do you have hot?
If yes. Next step
if no, the pos feed comes from the computer. Check that the PCM is sending the signal, if not then you might have a faulty PCM
Next, using a multi meter on volts scale, test the red/black and purple/white wires for 5 volts. Do you have 5 Volts?
Yes, next step
No, The 5 volt reference is provided by the PCM, possible PCM failure or PCM power feed problem
Next, test the pink/black wire for ground. Do you have ground?
Yes, then the optical sensor is not working and is probably bad. based on the other tests run this is causing your no spark condition. It’s time to replace your opti. You can also check for corrosion or damage to the opti connector and replace as needed.
No, the ground is provided by the PCM, possible PCM failure or PCM power feed problem.
Google dumdumdum.
__________________
Pete - '94 Formula
Driver only carries $20 worth of ammunition !
NICE!!!
I would love to hear the final result of all this. I have the problem with my 95. Runs great when it's sunny and dry, as soon as the rains come it starts crapping out. It will just die instantly but will restart. I don't have to fool with the throttle at all. I installed a new AC delco opti, opti harness, AC Delco ICM, MSD Coil & Plug wires and new plugs, TR55's and Racetronix kit in the last 6 months. The only thing I haven't changed is the MAF. I'm gonna burn this crapper if it's only a sunny day car!
I have done nothing but work on this pig since the day I bought it.
Anyone have any good leads for replacement harness connectors?
I have done nothing but work on this pig since the day I bought it. Anyone have any good leads for replacement harness connectors? 