Camry stalling

I have a 93 4 cyl Camry with a problem that none of the mechanics so far, including the dealer, could fix. After driving for a while the idle speed starts dropping until one stop light the engine stalls. It looks like it will run for ever at highway speed. Also seems to be heat related since it only happens in the summer. Here are the things that have already been checked, repaired or replaced:

EGR valve Thermostat Temperature sensor Distributer assembly MAP sensor ECU

I am getting very close to giving it to the Salvation Army. Does anyone have any other ideas? Have you seen this problem before? Thanks.

be

Reply to
Erhan
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This is a classic symptom of the EGR system not operating correctly. There should be no exhaust gas recirculation (EGR) at idle and the usual test for the EGR system is to apply vacuum to activate the valve at idle and see if the engine dies to indicate the system is working. I know you say the EGR valve has been replaced. Also check the vacuum diaphragm and vacuum modulator for the EGR valve. Have these checked with the engine hot and displaying these symptoms. Another less likely possibility, but often not diagnosed, could be excessive back pressure in the exhaust system from a partially collapsed muffler or catalytic converter.

Reply to
Daniel

I had the exact same stall-at-red-light problem, and changing the EGR Modulator did the trick.

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Try getting one for cheap at the local junkyard (if they have Toyota parts).

You might also look into a possible distributor O-ring slow oil leak. I had one, but it didn't help my stalling any.

Best wishes,

Michael

Reply to
mrdarrett

Thanks. Actually the EGR valve was only cleaned with carb cleaner.

Reply to
Erhan

Thank you. I'll give it a try. One thing I don't understand though is if the EGR system is the cause, why do the symptoms show only under warm weather?

be

Reply to
Erhan

To quickly check the EGR modulator, get a free loaner MityVac vacuum gauge from AutoZone. Connect the gauge to the hose from the modulator that goes into the EGR valve. Do you read vacuum during idle? There should be no vacuum from the modulator at idle, engine warm or cold.

Also, pull vacuum on the EGR valve. Does the engine quit? This is assuming the EGR valve operates normally and isn't stuck open at all times, but if so I would think too that the problem would be there when the engine is cold.

If it happens only when warm then can you keep the engine running by opening the throttle slightly? Idle Air Control valve on Camrys likes to stick shut. However, pre-97 has other things like thermo-vacuum valves etc that can cause problems too.

You can read about the IAC (> I have a 93 4 cyl Camry with a problem that none of the mechanics so

Reply to
johngdole

help.http://www.autosafety.org/article.php?did=972&scid=101>

Say, John... would the EGR vacuum switching valve likely be a problem, if he only stalls when it's warm out? Does it usually go bad? It's just an electromagnet solenoid coil, right?

I suspected the VSV too, when troubleshooting my stalling problem, but I stopped when the EGR modulator swap fixed it.

(Plus, the VSV is really hard to get to.)

Best wishes

Michael

Reply to
mrdarrett

== Online diagnosis is always a guess. However, the EGR system will not operate until the engine reaches operating temperature.

Reply to
Daniel

help.http://www.autosafety.org/article.php?did=972&scid=101>

Is VSV the blue switch with two hoses coming out of it near the coolant temp sensor? There is no information about it in my Haynes manual :(

Erhan

Reply to
Erhan

help.http://www.autosafety.org/article.php?did=972&scid=101>

I don't think so... I thought it was behind the intake manifold. (Between the intake manifold and the dashboard.)

But I could be wrong.

Michael

Reply to
mrdarrett

help.http://www.autosafety.org/article.php?did=972&scid=101>

See page 47,

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Not a particularly clear drawing, I'm afraid.

Michael

Reply to
mrdarrett

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