Need Toyota Technician Help

SAM-RAI · #1 (**permalink**) 11-10-2007, 10:47 AM

I got an 04 Camry I4 and I think the idle load sensor is bad. When the A/C is turned on, the RMP dropped below the normal idle RPM range and the whole engine/car shake like is going to die. I've taken to two different dealership 3 times this year and so far they can't find the problem since no code was set off. The service advisors said, they can not do anything or even try to fix it since they got no error code to go by. Also, this car is a drive-by-wire so in reality, there's no such thing as a idle load sensor to be replace if I wanted to.

Here's the BIG question for you trained techinician... What's wrong with this and how can I get this problem fix?

Thank you in advanced!

Sam

SAM-RAI · #2 (**permalink**) 11-12-2007, 04:26 PM

Anybody with automotive diagnostic training that can helps?

mustang67408 · #3 (**permalink**) 11-12-2007, 07:31 PM

Here are a couple of diag sheets for "NO IDLE UP"
The compressor sends a signal to the A/C ECU, The A/C ECU idles up the engine, there is no more "LOAD SENSOR device per say", but it uses the compressor signal to idle the engine up. This wont necessarily set a code, sounds like they were to lazy to check the wiring and ecu's.

If I had to GUESS, I would say it's the A/C control assy. The A/C ecu is built into it.

SAM-RAI · #4 (**permalink**) 11-12-2007, 10:44 PM

mustang67408
KE7WLF Master of Disaster,

Definitely a BIG thank you for that one. I will take this to the dealership and ask them to check it again.

Thanks,
Sam

mustang67408 · #5 (**permalink**) 11-12-2007, 10:59 PM

Quote:

Originally Posted by SAM-RAI Racing

mustang67408
KE7WLF Master of Disaster,

Definitely a BIG thank you for that one. I will take this to the dealership and ask them to check it again.

Thanks,
Sam

Let us know what they find or fix.
THANKS

SAM-RAI · #6 (**permalink**) 11-16-2007, 10:57 AM

Will do, thanks! I just have to make some time to take it back to the same dealership.

I just went back and checked all the PDF files and all the information I needed to know its all there. You are DA MAN mustang67408!!!

Thanks again!

yspert · #7 (**permalink**) 11-16-2007, 11:10 AM

clean the idle passage. yspert

SAM-RAI · #8 (**permalink**) 11-16-2007, 11:38 AM

Quote:

Originally Posted by yspert

clean the idle passage. yspert

Already done that. I don't think that's the problem at all. The no idle up issue only happens when the A/C turned on. Otherwise, it idle fine at factory setting under normal use.

SAM-RAI · #9 (**permalink**) 11-23-2007, 04:43 PM

Quote:

Update... I just got a call from the dealership service advisor and the he told me his techinician found nothing wrong with it. I went over and over and explained in details, but they still hold their ground as vehicle's working fine. Also, he said, the vehicle idle up about 10 RPM according to their test machine which is normal, which I think it's BS since it dropped in RPM and not up in RPM when A/C tunrned on. I'm going round and round here and going nowhere with it. I will pick my vehicle today and talk the their techinician directly in 1/2 hours. I'm really pissed off right now since they will charge me $95 for the diagnose and not doing anything to fix it and said, they can not duplicate the problem when in fact it's right front of them.

Mustang67408, What RPM range does the idle should jump up to when A/C turned on from normal idle?
I need your advise to talk to their technician about this 10 RPM idle BS.

Mustang67408, I really appreciate all your helps... Thank you!

I will quote myself from the above message when I was really pissed off at the time because it was going to cost me $95 for diagnose fee and they couldn't fine the problem. However, after talking to the dealership to try and find a solution, I was told by my service advisor Dustin that he will not charge me the diagnose fee. I'm glad to hear that from Dustin and thankful for his understanding. I think he will be a good service advisor in the future (he's a newbie in this business) as he's very easy and friendly to deal with and understanding of customer wants and needs.

I know this issue haven't been resolve yet, but I have to give credit to the Toyota techinician Wayne as well for trying to help me solve this on going problems with the idle up issue. These guys are among the best and very down-to-earth and easiest folks I've dealt with in the auto service industry in a long time. I understand they can not do anything at this time (put warranty claim to fix it) because the idle problem doesn't show up on the scan tool when they tried to duplicate it when I was there, but I know there's an ongoing problem when I drive it. However, the problem show up constantly when the weather is hot, but not always when the weather is cool like it is now. They recommneded me to drive the vehicle through the service bay and have them check it again when the idle issue drop to below normal so they can document that.

mustang67408 · #10 (**permalink**) 11-26-2007, 06:37 PM

It is supposed to maintain IDLE speed
Idling:
M/T 650 to 750 rpm
A/T 550 to 750 rpm

The idle speed is controlled by the Electronic Throttle Control System (ETCS).
The ETCS is composed of the throttle motor, which operates the throttle valve, and the throttle position sensor,
which detects the opening angle of the throttle valve.
The ECM controls the throttle motor to provide the proper throttle valve opening angle to obtain the target
idle speed.
The ECM regulates the idle speed by opening and closing the throttle valve using the ETCS. The ECM concludes
that the idle speed control ECM function is malfunctioning if: 1) the actual idle RPM varies more than
the specified amount five times or more during a drive cycle, or 2) a learned value of the idle speed control
remains at the maximum or minimum five times or more during a drive cycle. The ECM will turn on the MIL
and set a DTC.
Example:
If the actual idle RPM varies from the target idle RPM by more than 200 (*1) rpm five times during a drive
cycle, the ECM will turn on the MIL and a DTC is set.

THEORETICALLY
There is no set RPM idle up like the older vehicles.
It theortically should idle up and then settle back down to the target idle speed. This all can be viewed on the scan tool.
10 rpms sounds like it is doing nothing and there is a problem to me.

REALITY

I just went out to a 2004 Camry 4cyl and a 2006 4 runner V8

They both IDLE UP'd with the A/C approx 100 rpm.

This is what I would have expected to happen and be classified as normal.

SAM-RAI · #11 (**permalink**) 11-27-2007, 10:16 AM

Quote:

Originally Posted by mustang67408

It is supposed to maintain IDLE speed
Idling:
M/T 650 to 750 rpm
A/T 550 to 750 rpm

The idle speed is controlled by the Electronic Throttle Control System (ETCS).
The ETCS is composed of the throttle motor, which operates the throttle valve, and the throttle position sensor,
which detects the opening angle of the throttle valve.
The ECM controls the throttle motor to provide the proper throttle valve opening angle to obtain the target
idle speed.
The ECM regulates the idle speed by opening and closing the throttle valve using the ETCS. The ECM concludes
that the idle speed control ECM function is malfunctioning if: 1) the actual idle RPM varies more than
the specified amount five times or more during a drive cycle, or 2) a learned value of the idle speed control
remains at the maximum or minimum five times or more during a drive cycle. The ECM will turn on the MIL
and set a DTC.
Example:
If the actual idle RPM varies from the target idle RPM by more than 200 (*1) rpm five times during a drive
cycle, the ECM will turn on the MIL and a DTC is set.

THEORETICALLY
There is no set RPM idle up like the older vehicles.
It theortically should idle up and then settle back down to the target idle speed. This all can be viewed on the scan tool.
10 rpms sounds like it is doing nothing and there is a problem to me.

REALITY

I just went out to a 2004 Camry 4cyl and a 2006 4 runner V8

They both IDLE UP'd with the A/C approx 100 rpm.

This is what I would have expected to happen and be classified as normal.

I think that is how it supposed to be and that how it was operating before the IDLE UP issue started to happened. But according to Wayne the technician, it appeared normal on his scan tool as he can not put a claim to warranty to get it fix now until he can duplicate the RPM drop again. I can not blame him for that, but what got me really ticked was the previous service advisor, which I no longer work with told me it was normal because it's a 4 cylinder, and this when he drove it in the summer time and he did noticed/experience the car was idling way lower than normal and vibrate/shaking at the same time. In any case, I called Toyota corporate Customer Service and have it documented for future reference.

I thank you for all your help and will try to get this problem fix when the weather get HOT again. Thank you, mustang67408!!!