I have 89 z24 automatic. The car has been sitting for about 2 months. Any way I start driving it again and it runs just fine then out of no where the rpm's drop then jump back up then tne car dies. When it dies I can't get it to start right away, ti has to sit for a few minutes. When it starts it runs fine untill it decides to be a jerk again. The problem is very random, I could be driving doing 80Km/h and it will do it, I could be sitting at a stop light, or just pulling out of a parking spot. I thought that it might be the gas so I drained the tank and filled it up with new gas and had the run idle for about 30 minutes. After that the car ran fine the next time I drove it. Then it happened again. So I changed spark plugs, new air filter, oil change. I can't figure out what the problem is, any Ideas?

Mike

check your vacuum lines ... i had the same problem...

i had a tiny leak in the brake booster line

I'll check that when I get home, any other ideas, I don't want to have to keep going outside, it's so cold and we have a snow fall warning for tonight and into tomorrow, plus I am just getting over the flu. Don't want to sound dumb but how would i go about checking that? I have never checked for a vacuum line leak before.


Thanks

Mike

if its a 3 speed auto.. its the tcc sylinoid.. you can over ride this, there is a blue plug in the front of the tranny houseing or you can do it the correct way and just replace it... its not hard at all to do.. if you rig it you will loose gas mileage. TCC are natorious for those auto's.. good trannies but bad tcc's


**changes are here**

I might be wrong but doesn't a bad TCC Solenoid only make the car stall when you are slowing down, my car stalls even at a steady pace or when the car is accelerating, sitting still or slowing down. I could be wrong though.

hmm yeah, if its a tcc it usually can chug at a idle but your possible right I've never heard of the tcc dieing after the car has accelerated. Censored might be right... your vaccum lines might be off.


**changes are here**

The TCC solenoid is just an electro/hydraulic switch that engages the Torque Converter Clutch at about 50MPH/80KPH once the transmission is in top gear. The harder you accelerate the higher the engagement speed. The idea is to eliminate the hydraulic "slippage" that used to occur on older automatic tansmissions.


Also your'e right, Mikeyekim, the engine only stalls when coming to a stop if the solenoid fails, as the transmission is hydraulically locked in top gear.

You could drive for hours at cruising speed and not know the solenoid had failed.
It really is the same as coming to a stop in a manual trans car in top gear without depressing the clutch.

Really got my attention when my car decided stop signs were for wimps and really hard braking was needed to prevent forward motion.That's when I found Chuck Kichline's excellent TCC writeup.

Nothing in the TCC solenoid circuit would cause the engine to stall as yours does.

The vacuum line suggestion is probably the right way to go. Or:-

When was the fuel filter last changed?

Just thought you may have an intermittant blockage in the fuel supply, especially as the car has been sitting awhile.

Hope this helps

Alont

i have an oldsmobile with the 2.8 that has a small misfire until engine fully warms and then it wants to chug pretty bad when at a stop but fine the rest of the time. could this be vacuum as well?

I would almost bet that it's the crank position sensor. It will make your car stall since your computer thinks the engine is not running and it won't throw a code either. What happens is that it heats up and the signal from the sensor breaks down. Without the signal from the crank position sensor your coils don't know they need to fire, so it makes your car stall. The crank position sensor is located in the block on the left side of the engine (towards the passenger compartment). You unplug it and take one bolt out, then slide it out. Installation is the reverse of these steps.

If that's not it here's another idea from Ron Love


If it applies you could first, just disconnect the vacuum line, to see if it has any effect.



quote=Ron Love]Yes the egr can cause irratic idle and stalling if it's not working properly.Just remove it and clean all the carbon build up with some carb cleaner and make sure the metal pintal inside of it moves freely.I use a wire brush to clean as well.IF the pintal sticks or if ur egr has a visible rubber diaphram make sure it's not cracked,if it's a sealed unit and after cleaning it the problem is still evedent replace the part.Most egrs have a vac line going to them unless they are electrically connected ,u can just disconn the vac line and if the problem goes away that pinpoints the issue.Just try the above cleaning and go from there based on what u find.Worst case replace the egr with a new one.The symptoms are as stated idle weird once warmed up and almost stalling out as well.I hope this helps.



Alont

I am kinda thinking that it might be something with the fuel system, maybe the filter is cloged, I have never changed the filter since I have owned the car, so in about three years. Or possibly could it be the fuel pump? The car seems to just shut off, there is still electricity so I don't think it's anything electricall. I had the car ideling lastnight trying to solve the problem, and it just shut off. I could not get it to start for about ten minutes, and when I did it ran fine, nice and smoooth, no shaking or rough idel. Then agian it just shut off.

Mikeyekim wrote:I am kinda thinking that it might be something with the fuel system, maybe the filter is cloged, I have never changed the filter since I have owned the car, so in about three years. Or possibly could it be the fuel pump? The car seems to just shut off, there is still electricity so I don't think it's anything electricall. I had the car ideling lastnight trying to solve the problem, and it just shut off. I could not get it to start for about ten minutes, and when I did it ran fine, nice and smoooth, no shaking or rough idel. Then agian it just shut off.

That really sounds like the crankshaft position sensor. Next time it does that pull a plug wire and see if you are getting spark. If not that's the problem.

pull off your Ignition control module, (it's behind the 3 coil packs) and have it tested a few times to get it nice and warm.

i bet that's the problem