Corolla Stalling @hot

[wongat]

I did all the cheap testing I could. I brought it in to the dealer and they changed the MAP(Manifold Air Pressure) sensor. Part was $300 and they charged about $150 for diagnosis and labor for a total of $450. Now the car is FIXED and not stalling. Hope this helps other corolla owners with this problem.

[hyacinth]

Hello there,

I have a similar problem. Please let me know what you think.

It is a 92 corolla, auto transmission.

Originally, the car, after running on highway on around 65-70 miles , when coming to a full stop at a traffic light, will have a very rough idle - stutter/vibrate/hesitate , then it will shake and die down. The engine check will be ON. I will restart the car with gear on park, give full gas a few times and it will run fine.

This has happenned a few times in the past 2 years.

Recently when it died like this and I did the usual workaround, but it never comes back to normal..anytime I come to a full stop, the car will die. A full accelerator/throttle fails to fix it. All I have to do is to shutdown the engine and start it after many hours. The car will run fine without any problems.

This week, the car experienced this problem again, and nothing is working. Now whenever I put the car in drive or reverse gears, the car does very rough idle. I put it in Neutral or park, the idle is close to smooth. So it has become a big challenge driving the car around. I just start the car, it idles close to normal, I put it in drive/reverse gear, it idles extremely rough. Actually It cycles between extremely rough and a lesser rough idle. The whole car shakes. If I switch ON the rear window defrost or the AC or headlights, the car mostly dies and the engine check light comes on. But all along, When I start driving, it runs okay. But whenever I come to a stop, the problem happens.

I took it to Toyota yesterday, they did a whole day research and said they need to replace the IAC valve and possibly the entire throttle body. But they said they are not sure if it will fix the problem !!

I see that the symptoms are very similar to what is reported in this topic and would like to know your ideas.

Is it the EGR or the IAC/throttle body or something else.

What is the best way to fix it. Should I go to Toyota or some local mechanic shops.

Thank you.

[rarematters]

HERE IS YOUR ANSWER! I read the problems you are having with your 94 Corolla. My 1992 was doing the exact same thing. Exactly. Once warmed up - - - Stalling when slowing to stop, stalling when in reverse, but idling and running on straightaways and the expressway perfect. I chased this problem as I had reasonable access to a similar parts car, by replacing TPS, vaccum assy, spark plugs, coolant sensor, air filter, bumped idle, bumped timing and finally swapped a distributor. I even replaced the timing belt thinking I had slack issues. SAME PROBLEM after all these chores. Hmm. I called a well-known import mechanic and he said right off EGR problem. BUT... I had the same surprise you ran into, NO EGR where it is supposed to be (on the back of the intake area). I took the car over to his shop and he was perplexed at the absence of the EGR. We think possibly, since my car is a wagon, it may have California emissions or some Canadian modifications since many of these were special orders and dealers trucked wagons in from all over if someone wanted to buy one. The mechanic did the following and the car is now definitely fixed: On the top of the air intake just past where the snorkle attachs is a factory plugged set screw. Leave that alone. If you look closely you will notice another set screw on the front part (facing the front of the car) of the air intake with a rather large slot head screw. This controls air volume. I'm refering to an a metal/aluminum screw going into the intake/ throttle housing. NOT the big white plastic screw (with large spring) on the rear of the housing. One complete counterclockwise turn of the correct screw (towards open) immediately brightened the car's disposition and ultimately corrected the problem 100%. The reason the car did this is, carbon builds up in the intake and restricts the air supply just enough to cause the glitch under specific driving conditions. My car has 205K. When the car is cold it likes to be choked some, but as it warms it needs greater air volume. When you stop abruptly the idle air control valve requests a surge of air which is unavailable. The presence of carbon restrictions cause the engine to be caught off guard and it stumbles. I'm sure this simple task will solve your issue.

[rarematters]

I gave you the answer to the problem in my last reply. Trust me, my car did the exact same thing and I chased this problem for weeks. The answer I listed absolutely corrected the issue. I also read where you stated the new fuel filter made it worse. This makes sense. The new filter offers even more fuel to the air gas mixture as now you have no clogged restrictions on fuel whatsoever. The air setting and carbon blockage in your intake exaggerate the problem now that you have full fuel flowing thru the new filter. READ MY POST FROM 12 HOURS AGO TO SOLVE THE PROBLEM. I can be emailed at littlesilverspyder@insightbb.com.

[flywill]

I gave you the answer to the problem in my last reply. Trust me, my car did the exact same thing and I chased this problem for weeks. The answer I listed absolutely corrected the issue. I also read where you stated the new fuel filter made it worse. This makes sense. The new filter offers even more fuel to the air gas mixture as now you have no clogged restrictions on fuel whatsoever. The air setting and carbon blockage in your intake exaggerate the problem now that you have full fuel flowing thru the new filter. READ MY POST FROM 12 HOURS AGO TO SOLVE THE PROBLEM. I can be emailed at littlesilverspyder@insightbb.com.

I looked through the repair manual and also under the hood, but could not find the screw you described. Most matched item to your description is the IAC valve(idle-air-control), which is a module without any control adjust ments.

Is your car a FEI or carburetor? Normally carburetor has such mechanic adjustments as one of my neighbors showed to me.