Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: dRjENSEN on 14 July 2006, 14:54:06

Title: AirCon turns EM light on and off.. why!?
Post by: dRjENSEN on 14 July 2006, 14:54:06
Hola dudes..

When my car idles (after the motor has reached normal running temp) the EM light comes on and stays on until I either revs the engine, pulls aways or starts my aircon. Anybody with a decent guess on why it does that!? (I can actually turn the EM light on and off by starting the aircon and turning it off)

The only code stored is a 0100 and that should be the MAF (but I kind think thats a phantom code as theres is nothing wrong with the car).

Can the aircon turn the EM light on at all!?

Regards, dRjENSEN..
Title: Re: AirCon turns EM light on and off.. why!?
Post by: TheBoy on 14 July 2006, 16:17:40
There is a signal from a/c to engine managment to let it know state of aircon, but if your eml is coming on with a/c off as well, I think you have another prob.

What rpm does it idle at with a/c on and off?
Title: Re: AirCon turns EM light on and off.. why!?
Post by: dRjENSEN on 14 July 2006, 17:17:25
Well it idles at about 6-750 rpm with the aircon off and about 800-900 rpms with it on.. or there abouts. The aircon works fine though, and so does the car as a whole..
Title: Re: AirCon turns EM light on and off.. why!?
Post by: TheBoy on 14 July 2006, 18:26:00
I'm at a loss - not a prob I've come across before. Hopefully, somebody will be able to help out soon.

Is it the EML or the emissions light (describe what it looks like)
Title: Re: AirCon turns EM light on and off.. why!?
Post by: dRjENSEN on 14 July 2006, 19:47:26
It's the EML and it's definitely got something to do with the a/c. If I turn on auto on the a/c the EML dosn't come on, but if it's off or on ECO or anything else than auto then for sure the light comes on. Weird!
Title: Re: AirCon turns EM light on and off.. why!?
Post by: STMO123 on 14 July 2006, 19:50:45
Those idle revs sound a bit high. I seem to remember a post by Laidback saying that it should idle at about 450rpm?
Title: Re: AirCon turns EM light on and off.. why!?
Post by: JasonH on 14 July 2006, 20:17:48
It's about 500rpm climate off and 700rpm climate on with a 2.5 manual, but drjensen has a 2.0.
Title: Re: AirCon turns EM light on and off.. why!?
Post by: Matchless on 15 July 2006, 00:05:45
I wonder if there is an air leak, either throttle body - manifold, small breather or inlet manifold.
If air leaks in downstream of the throttle then the Idle Air Control valve will be almost shut at normal idle and the ecu could see this as an abnormal position for the valve. When a/c is on then a faster idle speed is set in the ecu so the IAC would open up...perhaps enough to be in the 'normal' range.
Title: Re: AirCon turns EM light on and off.. why!?
Post by: TheBoy on 15 July 2006, 10:57:46
Quote
I wonder if there is an air leak, either throttle body - manifold, small breather or inlet manifold.
If air leaks in downstream of the throttle then the Idle Air Control valve will be almost shut at normal idle and the ecu could see this as an abnormal position for the valve. When a/c is on then a faster idle speed is set in the ecu so the IAC would open up...perhaps enough to be in the 'normal' range.
And that would explain the stored code for the maf....
Title: Re: AirCon turns EM light on and off.. why!?
Post by: STMO123 on 15 July 2006, 16:13:35
Really good thinking Pete.
Title: Re: AirCon turns EM light on and off.. why!?
Post by: Admin on 15 July 2006, 23:17:59
I was thinking air leak then I saw Pete had beaten me to it!  ;)

Go check everything on the air intake side and make sure there are no splits and all connections are good.

It is not a big leak (that would cause the revs to go up and down a lot at idle) but enough to confuse the ECU.

Oh, and idle speed on a 2.0 should be around 600rpm with air con off and 700rpm with it on.

450rpm??  :o :o

 ;)
Title: Re: AirCon turns EM light on and off.. why!?
Post by: nixoro on 18 July 2006, 12:09:01
Quote
I was thinking air leak then I saw Pete had beaten me to it!  ;)

Go check everything on the air intake side and make sure there are no splits and all connections are good.

It is not a big leak (that would cause the revs to go up and down a lot at idle) but enough to confuse the ECU.

Oh, and idle speed on a 2.0 should be around 600rpm with air con off and 700rpm with it on.

450rpm??  :o :o

 ;)

Mine sits at just under 1k revs at idle on 97P where as the black omega sits at around 500-600rpm might have to check the breathers and get a new jubilee for the air intake as this maybe affecting it.