[Vulpine420]

Hey there, I've been having some issues with my 4 cylinder 1995 Camry and curious to what it may be. It has had this issue un-frequently for the past year or two but this summer it has gotten much worse.

After heavy driving, like the highway or long stop & go traffic, when the car comes to a stop the RPM begins to drop and the car starts to sputter and it will stall if the RPM falls to 0. If I hit the gas it will keep going, sometimes seemingly fixing itself, most of the time it will just start to stall soon as I slow down.

I've asked a couple people about it, first suggestion was the oxygen sensor but unplugging it doesn't seem to do anything. Another told me it was the fuel filter. And just today I had a guy look at it and he thinks it's being caused by a vacuum leak and pointed to a specific tube along the top manifold that might be the source of the problem,he said it had something to do with the connector or the chip controlling the vacuum pressure as unplugging the tube cause the engine to sputter in the same manner. I don't know what the part is called offhand but I could post a picture of it if needed.

Thank you for any help, I'd rather see if this is a self fixable problem before I take the car to an expensive mechanic that doesn't know either.

 

[bronzemaxell]

my 1993 camry 4cyl also had problem after driving on highway, need to keep the foot on gas pedal to keep the engine running, i thought it was the throttle body, but not.
and the problem getting worst everyday.
initially if it stalls, i can restart it right away and keep going
but a few weeks later, when it stalls, it won't start up until it has been cooled down
turn out it was the engine coolant temperature sensor malfunction, keep flooding the engine with gas when the engine has reached proper temperature.
if you take it to some mechanic, who is not familiar with this issue, they can blindly swap other suspected and expensive parts at your cost.

 

[Stillrunning]

And just today I had a guy look at it and he thinks it's being caused by a vacuum leak and pointed to a specific tube along the top manifold that might be the source of the problem,he said it had something to do with the connector or the chip controlling the vacuum pressure as unplugging the tube cause the engine to sputter in the same manner. I don't know what the part is called offhand but I could post a picture of it if needed.

He's probably referring to the MAP (Manifold Absolute Pressure) sensor. It measures vacuum, not controls it. Easy try-to-fix would be to replace vacuum hose connection to it. There is a test procedure you can get from the online manual which requires a volt meter.

 

[Jason.MZW20]

On deceleration, the TPS contacts the IDL pin to let the ECU know the throttle plate is closed and the idle speed control valve needs to take over. I'd suspect a sticking ISC valve first or possibly the ISC VTV plunger is malfunctioning.

 

[Mike Gerber]

I would start by cleaning the throttle body yourself, paying particular attention to spraying the cleaner liberally down in to the square or diamond shaped hole in the base of the throttle body. That hole leads to the idle air control valve, where your problem may exist. It's get's dirty and gummed up over time and the piston inside of it can not move freely to control the idle. Here's a thread with pictures on how to do it yourself. It's for the newer 5SFE engine but your's should be virtually identical:

http://www.toyotanation.com/forum/showthread.php?t=158097

Mike Gerber