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Ignition problem ICM or fuse?

comongoose

comongoose

New member
Hi I just recently got done with my bottom swap and decided to drive to UF for the first time with the GTP and of course the car goes and embarrasses me. As I pulled into the parking garage my car dies and won't start back up. Needless to say my day was ruined as i missed a chem 2 final, and had to get my roommate to give me a rigged towing service with his tundra. I hear the fuel pump and I have plenty of fuel pressure. I just changed the plugs because it had a slight miss, but I was starting to think it was due to the rockers or computer since it still has a stock tune and 1.9 rockers and l26 bottom end, and the idle was still rough after redoing plugs. Anyways I checked a plug and it wasn't getting any spark when turning the motor over. Tomorrow when there is light I will try to work on it. I am almost certain non of the cylinders are firing since the motor spins freely and fast but I hear non combustion of any sort(no popping sound), and the car won't start. My guess is the ICM or a fuse since I was pulling fuses out a week ago to do a compression test. What do you guys think it could be. Does anything else control all the coils? The only other thing I can think of is the computer. Also what do you guys think about the rough idle? Do i just need a tune? I have everything done in my sig and its still a stock pcm. Thanks in advance.
 


Also the only coed I throw is no o2 detection...because i have no 02 sensor hooked up right now. On a side note for those of you who have taken out the stock air box, where did you guys and how did you mount your computer?
 
I checked the coils and they are not getting voltage. I haven't had time to test the ICM yet, but I noticed that when cranking the motor, the TCS light was going on and off. Is this a sign that its the CPS or does that light always turn on and off when cranking before the motor starts?
 
Sounds like a CPS IIRC...but you might as well swap the ICM because I do not think that the CPS going bad has anything to do with your coils not getting any power.
 


dont swap the ICM yet. check all the wires going into the ICM. i had the same problem with my GTP and all it was is one of the little connectors kept losing connection. what u gotta do is take the connector out and bend the little insert outward to make a better connection to the pins on the ICM. be careful not to rip the wire out of the connector. you can use a T-pin to bend them out while its still in the connector but if u can get the wires out without damaging them that would be better.
 
forgot to add this in the last post.. take the icm off and get off any rust on the mounting surface. use a wire brush to clean it to make sure it has a good ground.
 
JayGTP02 said:
dont swap the ICM yet. check all the wires going into the ICM. i had the same problem with my GTP and all it was is one of the little connectors kept losing connection. what u gotta do is take the connector out and bend the little insert outward to make a better connection to the pins on the ICM. be careful not to rip the wire out of the connector. you can use a T-pin to bend them out while its still in the connector but if u can get the wires out without damaging them that would be better.
Click to expand...
Ok well I saw wires that were going towards the CPS that were cut by the belt. None of them were touching just missing insulations. I re-connected them and insuled them, and that didnt fix the problem. I then took the ICM to autozone and it checked out good. I'm not sure what you mean by bending the insert to get a better connection to the icm. It looked pretty good since the connector is bolted in. Maybe I am missing something here. DO you guys suggest I replace the CPS? I find it hard to believe that sensor is already shot though since it only has 26,000 miles on it, since it was on the l26 block i bought.
 
anyone???? PLease guys if you have nay insight I greatly appreciate it, this is now my only car as i just sold the tl and its being a gremlin.
 


ok just tried a new harness for the icm, and guess what? It still wont start. I have never had a car just die on me and not start back up like this. Its getting to be frustrating. What else can I try? Is the only thing left the cps? could this be a pcm problem?
 
by the inserts i meant the metal connectors on the ends of the wires that make contact with the pins on the icm. you have to take the wire out of the harness to really see what i mean.
 
"Well next time I try givin the guy help I'll just keep my mouth shut and let you do it." -bluegtp91-

whats ur problem? whats with the attitude? i was just tryin to save the guy from buying stuff he dosent need. i had the same problem and it was just a loose connection on one wire. and i didnt have a problem after that. but, aparently his problem goes deeper than a lose wire. so im sure ur suggestions will help him now.
 
I just have monthly spurts don't let it bother you. Look at it this way. If you were giving your advice to someone who needed help then someone else came along and told them...NO DON'T DO THAT, TRY THIS INSTEAD. I think you might be a bit irritated too.

Now...so you know it isn't the connectors^^ suggested and it isn't any plugs/wires/ignition issue...I have a question...are you getting fuel? You say it starts and dies...can you start it back up right after? Can you hear the pump prime when you turn the key "on"? If so and you start it, after it dies and you do this a couple times can you smell raw fuel? If so...(guessing since you have a '99) try the Fuel Pump Resistor mod...open up the fuse box and follow this pic...

bypassmod.jpg


My buddy's '99 GTP drove fine since he bought it last year then driving it home from the store the other day it just died coming down the street. We could start it...it would run for a split second, try to stay running, then just die. Did that mod to the sensor and it started like a charm. Only bad thing about running that mod for a long period of time is it bypasses the Fuel Pump and makes it run in "High" mode all the time putting more strain on it...thus meaning it will fail a lot faster...so after you do it...figure out where to get a new fuse ;)

If this doesn't fix it then idk...guess you can try replacing the CPS next...
 
oh well sorry, i didn't mean to say "dont ever do that!" i was just suggesting something to try before buying parts. didnt mean to undermine your suggestion. wasnt my intention at all..
 


bluegtp91 said:
I just have monthly spurts don't let it bother you. Look at it this way. If you were giving your advice to someone who needed help then someone else came along and told them...NO DON'T DO THAT, TRY THIS INSTEAD. I think you might be a bit irritated too.

Now...so you know it isn't the connectors^^ suggested and it isn't any plugs/wires/ignition issue...I have a question...are you getting fuel? You say it starts and dies...can you start it back up right after? Can you hear the pump prime when you turn the key "on"? If so and you start it, after it dies and you do this a couple times can you smell raw fuel? If so...(guessing since you have a '99) try the Fuel Pump Resistor mod...open up the fuse box and follow this pic...

bypassmod.jpg


My buddy's '99 GTP drove fine since he bought it last year then driving it home from the store the other day it just died coming down the street. We could start it...it would run for a split second, try to stay running, then just die. Did that mod to the sensor and it started like a charm. Only bad thing about running that mod for a long period of time is it bypasses the Fuel Pump and makes it run in "High" mode all the time putting more strain on it...thus meaning it will fail a lot faster...so after you do it...figure out where to get a new fuse ;)

If this doesn't fix it then idk...guess you can try replacing the CPS next...
Click to expand...
NO, like i posted in the beginning. It will not start at all. It has fuel pressure and the pump primes. The only thing left before I look to the pcm is is the cps. Does any one know if its possible to fry one, from having exposed wires? It only has 26k miles on it so i find it hard to be broken form normal wear and tear. Im thinking the exposed wire bight have affected the resistance to the 10v power to it and messed something up. I am not sure if thats the way it works though.
 
OK well it looks like it was the CPS. I guess if you chop up the wires you most likely will fry your CPS. NOw for some reason I can't get that dang crank pulley on right. I cant get it to key in. My pulley doesn't move as freely as synthetic shield's does in his write up.
i have to hammer my pulley on and it stops spinning any way i put it. Then when i tighten the crank bolt down it tears a new notch in the pulley. I already tried it three times. The car idles really fast bec i i put it a little to the right of the notch. and the third attempt i just did i think i feel in the same notch i made. this is getting frustrating. At least i trouble shoot the problem though. hopefully tomorrow it will be drivable. I am done with it for tonight. Does any one have any tips for getting back on? Also does any one have any suggestions with mounting the pcm when you take out the stock air box?
 
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