Hi all -

I've had a very annoying stalling problem going on for about 3 years now. It starts every year when it gets to be about 30 degrees out, and is definitely temperature-related. Warm weather, no problem, ever.

Symptoms:

Stalls when idling, usually within one minute of starting/restarting, and after "loping" a few times with the idle speed dropping progressively on each cycle.

Stalls when shifting into gear and then lightly accelerating; I can sometimes keep it from stalling by goosing the gas repeatedly.

Frequently kicks back when starting as if timing is screwed up, but runs fairly well at speed. Very slight misfiring occasionally at higher road speeds, but no pinging.

What it's probably not - (These are the things I've replaced, cleaned, or tested):

Plugs, wires, cap, rotor, idle air controller, O2 sensor, TPS, vacuum leak, MAP sensor, air filter, fuel filter, valve train, compression.

I have a definite suspect in mind, but I wanted to know if these symptoms sounded familiar to anyone, particularly the fact that it's strictly temperature-related.

Thanks, John D.

 

From what I've read on here lately, it could be the PCM.

 

PCM was my #2 suspect; still wondering if anyone can confirm my first. I don't want to say what I think it is until I can get some more input.

Another clue; the engine runs a little rough at all speeds.

Anyone?

 

Shameless bump.

 

fuel related?

 

Thanks for the response.

Very doubtful. Fuel pressure is good, and it's not like I have bad fuel/water in the tank. This happens every year when it gets cold out, like clockwork. Can't see how a fuel problem would be temperature-related.

I'll go ahead and say what I think it might be; crankshaft position sensor going bad. I've seen electronic components get affected by cold before; pickup coils for example. CPS might explain the kicking back on startup if the PCM doesn't know where the crankshaft is.

Someone else on here had an engine that was misfiring badly after an engine swap and a new CPS fixed the problem.

Does this sound like a reasonable fix to anyone out there? Open to other suggestions as well. Thanks.

***

Forgot to mention: PCM is displaying no meaningful codes. Just the usual crap about things my truck doesn't have: A/C clutch, tranny overdrive solenoid, tranny temp sensor.

 

Sorry for the bump, but I've got to decide whether or not to blow 60 bucks on a crankshaft position sensor that might or might not solve my problem.

Can anyone tell me if a failing CPS would explain my symptoms? Thanks.

 

It is possible. Take it to your local auto parts store that has a code reader. Ask if they can read real time data as well. If they can, have them have a look at coolant temp, when the engine is acting up. A wrong temp reading will screw with what the computer thinks fuel requirements would be....... and give you some rather interesting problems.

I don't think that's it though...... that would be more of an issue when the engine was warm, or, ALL the time....... if the engine runs great once it warms up, and the problem goes away........ I would take a hard look at CPS, CKPS, and PCM....... I do not know of any way to test any of those components, aside from replacing them.