Car:
- 1997 N/T Man Trans

Problem:
- Car starts and runs fine when cold...after idling for several minutes the car warms up and starts running like crap (feels like the timing is way off) until it dies and won't restart. After the car cools down I can do it all over again.

Things I've already checked:
- ECM Replaced (I have a spare from same year/ make/ model) No change.
- Coolant Temp Sensor replaced. No change
- IAT Sensor bypassed. No change
- Originally I thought it was a fuel problem. However the car has a new pump, and pump relay and the filter is clean.

It seems like a temp sensitive timing problem. Any thoughts?

Thanks

You sure you dont have a leak from the radiator hose that shorted out the new sensor? That seems to be the popular spot for the coolant to fall.

Nope, its all dry. Considering the symtoms I would've thought that sensor was doing it for sure.

What else can be effected by the vehicle temp and change the spark/fuel/timing?

Have you checked your crank/cam sensor? Just a thought.

Can you verify the timing is actually adjusting via a datalogger?

I thought about the Cam Sensor, but wouldn't it screw it up all the time and not just when its warm?

I don't have access to a data logger. I'm not for sure its the timing but it sure sounds like it.

It idles and revs just fine when cold, but as soon as the temp guage starts moving it starts running worse. I have to rev it to keep it running and then it gets so bad it won't run at all.

I unpluged the IAC sensor (center back side of Intake) but what is the IAC on the Throttle Body? Could this be affecting it? I didn't think it was temp dependent.

The cam sensor could be acting up as it gets warm. Your crank and cam sensor are the main two sensors that mess with your timing.

Your IAC is on the throttle body.

Yeah, I ment to type IAT.

Ok, I took off the TB and cleaned it with brake cleaner. I read some threads where people had trouble with the IAC getting gummed up and not idiling properly.

Update:
Now it won't start at all. It cranks and spits, sputters, and backfires but won't run. Still sounds like timing is off but now it won't run even cold.

Where is the crank sensor?

Yeah I was having the same problem!!! Can anyone help us out???

Did you recently change the timing belt? It sounds like when my cam sprocket dowel pin sheared off, I haden't used any loctite when I put in my sprocket bolt and after a few hundred miles it backed out just enough that the pin sheared, it started great for a while then the ecu kept pulling timing as it warmed and eventually wouldnt start once the pin fully sheared, luckily it didn't damage anything, it just stopped spinning just out of the way of everything, but it backfired like a mother until I saw the gear wasn't spinning and stopped. I was lucky I had an extra exhaust cam

Same exact problem here, also sporting the p1390 code. Is the code related? I haven't messed with anything related to the timing belt. Ive also replaced the cam sensor, coolant temp sensor, IAT sensor, PCV etc. .... will you get a 1390 code if the crank pos sensor has taken a crap? Belt has plenty of tension, and is in great shape(no cracks/ splits etc.)I find it hard to believe that its slipped a tooth or more, w/o me messing with it?!?! Could it be related to the EGR block-off??

I replaced the timing belt about 20k miles ago when the engine was rebuilt...no problems until now.

I thought it might have jumped a tooth, or maybe the tensioner went bad, but I checked the belt, gears, and tensioner and I saw no problems.

I ordered a new Cam Sensor and Crank Sensor so we'll see what happens after that. Nothing like throwing money at it to fix it!

i think its the IAC. try starting it again. If you can keep it running by pushing down on the gas pedal (it will run like crap, but it will still run) and it dies the minute you take it off, then its the iac. And, with your TB removed it will be a good time to clean the back of your throttle plate.

Sounds like the problem i had till i changed the crank angle sensor. try that, it made me happy

Thanks to everyone for the help. I replaced the Crank Sensor and it works great now.

Must have been a coincidence that it started going bad only when the car warmed up.

Believe me , it's not an coincidense. I still don't know why, but when mine warmed up, it did excacly the same thing

Originally posted by arsenaultal
Thanks to everyone for the help. I replaced the Crank Sensor and it works great now. Must have been a coincidence that it started going bad only when the car warmed up.

Great! Thanks for keeping this thread updated as well. Great title, good info here. Great thread! :thumbsup

Originally posted by cc8balla

Originally posted by arsenaultal Thanks to everyone for the help. I replaced the Crank Sensor and it works great now. Must have been a coincidence that it started going bad only when the car warmed up.

Great! Thanks for keeping this thread updated as well. Great title, good info here. Great thread! :thumbsup

Excellent. X2.