05 Camry high idle problem

[Woody51]

Hi all, new to this forum

I have a problem with my Camry 170k on the clock
Took it out a few nights back and the high idle was stuck on, after about an hour the idle gradually dropped to normal.
The next night it would not start and run unless I keep the accelerator pedal pressed slightly, after warming up it seems to run fine, The high idle has not returned
I have seen a few suggestion on cleaning the iac valve with Carbie cleaner, so I tried that and it made no difference
Any ideas ?

[Woody51]

I should have mentioned that the problem occurred after the car hadn't been started for 6 weeks

[Brian R.]

You should also mention which engine you have. Is this with the A/C on or off? Has it returned to normal or is the problem still a problem? Check the codes in the ECM to see if there are any stored.

[Woody51]

Originally Posted by Brian R.

You should also mention which engine you have. Is this with the A/C on or off? Has it returned to normal or is the problem still a problem? Check the codes in the ECM to see if there are any stored.

Thanks Brian I forgot to mention it's a V6
I just purchased a code reader which only arrived this morning so I will check as soon as I get a chance
Also the engine fault light is not on
It is a Sportivo so in so far as the AC I guess all the times I have tried the climate control is on I will try without it as well

[Brian R.]

There may still be codes stored in the ECM in spite of there being no CEL showing. Are you still having the high idle problem?

[somick]

Check the battery. Is it still good?

Has the throttle body been cleaned. If not, this might be your problem.

I would also seafoam the intake.

Good luck,

Sam

[Woody51]

OK guys thanks for your help, I have cleaned the throttle body with a carbie cleaner, sadly we can't get Seafoam here in Australia.and the battery is good
I ran my new code reader and there are no codes stored
Problem still persists

[Brian R.]

Check your engine coolant temperature sensor.

[somick]

Originally Posted by Brian R.

Check your engine coolant temperature sensor.

How about coolant level?

[Woody51]

Originally Posted by somick

How about coolant level?

Coolant level is OK
How do I check the sensor (doesn't it bring up a code if faulty) ?

[Brian R.]

No, faulty ECT sensors don't bring up a code. They normally operate over a very large range. There is no way for the ECM to know if the resistance is wrong or not.

Disconnect the sensor, then test the resistance of the sensor with a volt-ohm meter - I usually test it at room temperature (engine cold, 104F in summer) and at operating temperature (engine hot, 176F)

Approx. 15.04 kOhms (–20C, –4F)
Approx. 5.74 kOhms (0C, 32F)
Approx. 2.45 kOhms (20C, 68F)
Approx. 1.15 kOhms (40C, 104F) <-
Approx. 0.584 kOhms (60C, 140F)
Approx. 0.318 kOhms (80C, 176F) <-

[Woody51]

Originally Posted by Brian R.

No, faulty ECT sensors don't bring up a code. They normally operate over a very large range. There is no way for the ECM to know if the resistance is wrong or not.

Disconnect the sensor, then test the resistance of the sensor with a volt-ohm meter - I usually test it at room temperature (engine cold, 104F in summer) and at operating temperature (engine hot, 176F)

Approx. 15.04 kOhms (–20C, –4F)
Approx. 5.74 kOhms (0C, 32F)
Approx. 2.45 kOhms (20C, 68F)
Approx. 1.15 kOhms (40C, 104F) <-
Approx. 0.584 kOhms (60C, 140F)
Approx. 0.318 kOhms (80C, 176F) <-

Hmmm, Checked the sensor, and it came up with pretty much exactly your figures

[Woody51]

Forgot to mention that my Camry is running on LPG, so was not much build up in the throttle body.
Do you think it would be fair to say at this stage that the stepper motor in the IAC has probably died, and time to replace it ? I know they are costly but seem to have eliminated most other things

[Brian R.]

Check the following first:

AIC VACUUM SWITCHING VALVE.
The resistance between the two terminals should be 37-44 ohms at 20 deg C. No continuity means bad VSV.

With no voltage applied to the terminals, there should be airflow from the small port next to the terminals (Port E), to the filter connection (large diameter connection closest to the terminals).

With battery voltage applied to the VSV terminals, there should be airflow from Port E to the small port behind Port E and pointing in the opposite direction as Port E.


AIC VACUUM SWITCHING VALVE ASSY NO.1
Check that resistance between the terminals is 33 – 39 ohms at 20 deg C. No continuity means bad VSV assy.

With no voltage applied to the terminals, check that air flows from the small port closest to the terminals (Port B) to the filter connection (large diameter connection closest to the terminals).

When battery voltage is applied across the terminals, there should be air flow from port B to the small port furthest from the terminals (on the same side of the VSV as Port B).


The difference in appearance between the two VSV systems is the AIC VACUUM SWITCHING VALVE has one small port pointing in the opposite direction from Port E. The VACUUM SWITCHING VALVE ASSY NO.1 has two small ports pointing in the same direction and no port pointing in the opposite direction of the other.



AIR CLEANER CAP SUB–ASSY
The ACC sub-assy has three ports - One straight port which is Port C, and two right-angle ports. The one closest to Port C is Port A, and the furthest away from Port C is Port B.

Cover port C with a finger, and check that air flows form port B to port A.

Cover Port C with a finger, and check that air does not flow from port A to port B.

Plug ports A and C securely, and apply 60 kPa (450 mm Hg, 18 in. Hg) vacuum to port B, and check that there is no change of vacuum after one minute.

[Woody51]

Thanks for all the help here guys
It has really helped me track things down
After eliminating a lot of possibilities thanks to the help here I decided it had to be the IAC valve, so I contacted the local dealer and got a price for a replacement, $537 AUD .
So I figured try anything before spending that money. I figured why not and drowned the mechanism in WD40, I let it soak for about 30 mins then gave it a blow out with air.
And guess what ! it is now working, the only question I guess is will the WD40 have some other detrimental affect.
If I'm lucky just saved some big bucks