[Terence Ruetz]

Hi..... Ive been having problems with my 1995 toyota camry LE v6 3.0L Only when i run it during the hot days. After 30 minutes of driving or so. Everytime i come to a stop my rpms will be at 1100 instead of going down to 800 or 750. When i put it in park it will go up to 1400-2100. Depending how long i drive it after knowing the rpms are sticking. Ive cleaned the throttle body 3 times still does it. Ive unplugged the iac and the car ran just fine. But it didnt it again to me today. So it cant be the iac or the throttle. Any suggestions ? Thanks also... It never does this at night. It seems like its happening at operating temperature.

 

[mcgowaw]

"It never does this at night. It seems like its happening at operating temperature." so you can't get it to go into closed loop driving it at night? that's strange.

when you say you cleaned the TB and IAC, did you remove the entire air box, rubber snorkle, throttle body from the intake, then remove the IAC from the throttle body, remove the egr valve from the throttle body, clean all the parts with seafoam and a toothbrush, dry them out and use a 9v battery of 12volts from the car to verify the IAC is opening and closing properly, per the haynes manual? Then did you also verify that the egr valve opens with a vacuum and the egr modulator is allowing vacuum through it and the egr vsv passes a vacuum with 9 or 12volts applied to it?

at least, that's the things i do to fix similar problems, assuming all the regular maintenance items like plugs/wires/pcv/rotor cap/distributor cap have been replaced and there's no oil inside the distributor, etc., and there are no CELs.

if so, then we can move on to long term fuel trims and o2 sensor graphing to try to find out what's going on.

tony

 

[Stillrunning]

Usually when you unplug the IAC the engine does not idle well or at all. That leads me to think either there's a vacuum leak or your throttle plate is not closing properly. It should be shut when your foot comes off the gas pedal and idle control is with the IAC.

The other possibility is the ECT (engine coolant temp sensor) is misbehaving and telling the computer the engine is still cold and it needs high idle - which would be controlled by the IAC. You can check by testing OHM readings when engine hot. Wrong readings from the ECT will also make the engine run rich.

Also if thermostat is not maintaining temp then that will affect ECT - although I don't know what the minimum temp is for coming off fast idle. What kind of temp gauge do you have?

Fuel trims are always good information if you can get them.

 

[mcgowaw]

+1 on the bad running when unplugging the iac SR.
don't make sense somehow. also not being able to get it into closed loop at night but can in the daytime was something i've never heard of either.

op, unplug the green or grey 2-wire connector on the top of the coolant temp sensor (haynes will show you where it's at) when it idles badly and see if it works ok then. if so, then replace it.

tony

 

[Terence Ruetz]

When i run it at night it seems fine like mint. I will drive it for over an hour and no problems. I have had it happened once at night but that took a long time for it to kick on. What i did was, removed the vacuum hoses and sprayed the throttle down and filled the iac hole with carb cleaner... Let it go down and do it again. Also used toothbrush. Also for ECT... How can it still cause the car to have high idle when the iac is unplugged? I got the car from someone it has 238k when i pulled it out of the parking lot it was way worse. It was happening instantly. I looked at the oil change sticker and it said it was changed in 2013. Ive put 1k in the car so far. I will some how have to try and unplug the ECT while i put the car in park? Also when this happens and the rpms are very high in park lets say 2100. If i put my foot on the gas to revv it to see if the rpms will go down itll only go up. I just dont see how the ECT can be telling the iac the car is cold when its at operating temp when the iac is unplugged. Theres no check engine light s on now or when i got the car. I had it scanned and there was no codes. Thanks guys

 

[Terence Ruetz]

If i unplug any of those grey connectors for the ECT while the car is stuck in high idle... Whats the worse that can happen. This is my second car so im not well experienced with these kind of things.

 

[mcgowaw]

you really need either a haynes or fsm to start doing repairs on this car yourself. you're gonna be lost without one.
it's a 2 wire connector located on top of a coolant pipe, possibly on the passenger side of the car but i have a v6 so not sure about yours. mines a green connector but i've sen grey also. ignore the other sensor with just 1 wire in the coolant pipe. if you unplug the 2 wire, with engine hot and running badly, it will either make it run better or cause no change at all.
let us know.
tony

 

[Terence Ruetz]

Thank you Tony i will give it a shot. Also of that doesnt work what would be the next thing i should be looking at ?

 

[Terence Ruetz]

1+ id like to add. It seems to happen in the city. When i drive in the country it doesnt happen for sometime. I can drive it on the highway and thered be no problems afterwards.

 

[Terence Ruetz]

Also can i try this on a cold start up because with the iac connected it will ramp up to 1800 rpm with temperatures of 30 degrees outside weather. Now that the iac is unplugged it will start up at 950 rpm @ operating temperature in park its at 1100 . when i drive it 850 rpm at stop light. Im going to replug the iac then

 

[mcgowaw]

where in the world do you live that it's 30 degrees outside in august?
tony

 

[BMR]

where in the world do you live that it's 30 degrees outside in august?
tony

I bet he's talking degrees C. 30C = 86F

 

[Terence Ruetz]

Yes 30 degrees Celsius so 86 F

 

[Stillrunning]

Don't get confused, the IAC is controlled by the computer from sensor inputs such as ECT. The IAC does not control itself.

I think right now you'd be better to check for vacuum leaks.

I think this 95 V6 is OBDII, which means you can pull fuel trims as well as ECT readings off the computer. Confirm this is OBDII, because from there you can get a lot of useful information from a scanner.

 

[mcgowaw]

SR, you're correct. 94 and above v6's are obd2.
tony

 

[Terence Ruetz]

Thanks guys I'll let you know when i get it scanned