[SOLVED] Prizm/Corolla stall problem

I've asked mechanic not to change distributor till he is certain that that is what is causing this problem. Regarding EGR - Would this not happen at every idle? In my situation it is that threshold point at which car stalls. Once it passes that threshold, even if I idle, I do not have a problem.

Timing belt replaced 15K miles back, Tune up done at same time (spark plug, air filter, ign cap, wires dist - changed). I think brand is aftermarket.

I just realized the other "Usual Suspects" thing that would cause odd stalls at idle - have your mechanic pop apart and clean out the Idle Air Control Valve and the passages going in and out of the throttle body to it.

This is a little motor driven vane valve that adjusts the air bypassing the main throttle valve (attached to the other end of the gas pedal) for idle speed. If the IAC Valve gets full of dirt and gack and sticks, the EFI computer can't turn it to trim the air for idle speed. Depending where it's sticking the engine either races or dies.

The shops always tell you to replace the entire IACV and not clean it out, but that's because they don't want you back with the same problem later. (For dealers, a callback on a repair weighs heavily on all the customer satisfaction surveys...) But the IACV is expensive and rarely dies, all it needs is a flush with healthy shot of Carb Cleaner.

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If the EGR valve is stuck fully open then the problem would probably appear at every idle. If it is not fully closing, then the problem may be more severe during warm up. If the plastic body on one of the vacuum switching valves is cracked, then the problem may only show up when the engine is warmed up. Also, if there is a cold start enrichment problem, then the problem would clear up when warmed up.

If the ignition wires, rotor, distributor cap, and spark plugs are aftermarket, check their condition, especially the spark plugs.

As Bruce mentioned, check the idle air control valve to make sure it is not gummed up.

Hello,

Mechanic had a used distributor that he wants to install on another Corolla. However, he has replaced my distibutor and car seems to be working fine. Although, I can feel a slight vibration once a while thru the brake pedal (when car is started from cold). As car gets warmer this pulsation (at lights or traffic stops) from brake pedal gets reduced and car seems to run much smoother than what it did while it was getting to operating temperature. I do not know if this fix is temporary but we shall see soon.

Thanks for your help,

Hello,

I was taking a look at the messages once more and realized that I might have missed a point.

The problem actually is:

Car is cold either in the morning or in evening after it has been in the garage the whole day. After starting, the first mile is fine. I could idle, stop at light, no problems. It is only during the second mile that everything breaks loose. During the second mile, if I stop at light or traffic, then engine gasps, shakes a bit and dies.

Now I mention miles because that is how my commute is. It could very well be that once temperature reaches a certain point (in my case it reaches during the second mile) and hence it really does not depend upon miles but rather a threshold temperature.

So, do all the solutions mentioned apply in this scenario. If I face an exhaust issue at idle in second mile, why don't I face the same in the first mile?

Thanks,

The list of things to check that I provided should be checked regardless of the length of your commute.

I do not recall mentioning an exhaust issue, but the EGR valve may cause a problem in the second mile that it does not in the first mile.

Hello,

Now the car is not dying on me but still the performance is rough while it is cold. Once it warms sufficiently, it runs fine.

Would the possible problems that you gave in earlier posts go away if there is a new distributor? i.e would a new distributor cause EGR valve not to stick or vacuum leak to not happen? Or is it because the new distributor is giving a good spark for the time being and all these possible problems are lurking underneath?

thanks,

I think you may wish to find a competent technician to work on your car from now on ;-)

A new distributor will not have any effect on the EGR valve and will not cure a vacuum leak unless the vacuum advance for the distributor is leaking (which I doubt is happening).

I seem to recall that a new temperature sender for the electronic control unit cured the initial problem. Was the replacement temperature sender an OEM or an aftermarket part?

Did someone check EGR operation?

I do not think anything in the distributor is causing the problem unless the ignition timing is not set properly.

Hello Ray,

I do understand your advice regarding getting another technician to look at the car. My problem is how do you say no to a family friend who has been working on all our cars for the past 20 years; our families are very close; wives are good friends, kids are in same school. And we've not had any problem till now....sigh, sigh, sigh.......

After he put the distributor in (I have not been charged for it yet, since he anyway needs a distributor for a Corolla), car no longer idles during the first 2 miles etc. It runs rough till it gets warm. I can sense a different vibration on the brake pedal while car is warming up. That is why I was wondering if a car that had issues with EGR etc that you and Bruce had mentioned, then replacing a distributor would not have made any effect. But in my case, it has made an effect.

Initially, he had changed fuel filter and done inductive cleaning. Nothing else.

Thanks

Your situation is a toughie which calls for some delicate "coaching." Before the advent of dealer technician hot lines and on-line troubleshooting, one of the things I used to do as a district service manager is help dealership technicians fix problem cars. In most cases, the dealership's best master technician would be working on the problem, so I had to steer them in the right direction without insulting their technical skills and experience. One of the good things about working on Toyotas is that they are very consistent and one-of-a-kind problems are not very common, so my bag of tricks fixed every car I looked at except for 2, where I had to call the field technical specialist in our office to look at the cars.

A clogged fuel filter is more likely to affect how an engine runs at higher RPM than at idle, so if the problem is with idling, I move a clogged fuel filter to the bottom of the list of suspects.

One of the things I've run across is that replacing a good part, like your distributor, can sometimes change the nature of a problem, leading the person working on the car to focus on the part that was replaced, sort of a false clue. While messing with the distributor, vacuum hoses can be disturbed, and the EGR is controlled by vacuum.

The reason I keep saying to check the EGR is that you can check it in less than 5 minutes with a golf tee, and if it is working, you can eliminate it as a cause and look elsewhere. Disconnect the vacuum hose to the EGR valve, stick a golf tee or a screw into the vacuum hose to block it off, and see if the problem goes away. If the problem goes away, the EGR valve may have exhaust deposits built up inside that is keeping the EGR valve from closing all the way.

Back to the distributor, I cannot think of anything in the distributor that would affect how the car runs while cold but not while the engine is warmed up except for base timing. I can't imagine a competent technician not checking base ignition timing when replacing a distributor, but I have seen people just make a mark and line the distributor up with the mark instead of checking timing with a timing light.

Ray,

Thanks for understanding.

I am going to talk to my mechanic about EGR and Vacuum leak and ask him to check for those 2 things. However, I was wondering why does the EGR or Vacuum leak occur only for during the first few miles and not when the car gets hot. If EGR gets stuck, then it should get stuck at high speeds also. And if there is a vacuum leak then also why does it happen only during the first few miles. Should it not happen when car is hot too.

Thanks again for your help

I have seen vacuum leaks that only occur while the engine is cold or while the engine is hot. Most vacuum connectors are made of plastic, and if they have a hairline crack, the expanding or contracting plastic due to changes in engine compartment temperatures can make vacuum leaks come and go.

I doubt if the problem is due to an EGR or vacuum leak problem, but the person working on the car needs to take a methodical approach to diagnosis rather than just swapping parts, and checking the EGR and manifold vacuum takes only a few minutes.

The next thing to check if the voltage coming from the coolant temperature sensor for the ECU, and if that doesn't work, then the car needs to be taken to a shop with a computer diagnosis system that can monitor engine operating parameters while the condition is present.

Thank you everyone for the help.

After my mechanic replaced the distributor, I initially experienced that the car ran rough till it got warm and also the car did not seem to have the same acceleration as before. Went to mechanic and he re- aligned the distributor. After this, the car has been working as it was before the problem of stalling when cold. It's been about 4-5 weeks and no stalling.

Just thought I'll let everyone who contributed to this post know this.