Club G40 Forum

Technical => Engine and Transmission => Topic started by: GAF2 on February 21, 2009, 07:26:21 pm

Title: CO readings?
Post by: GAF2 on February 21, 2009, 07:26:21 pm
I am having a problem with my idle and i want to check the co meter am i right in saying that i should get 550 560 ohms across pins 1 and 3, what i dont know is when do i take this reading is it at a perticular rev range or just at a standart idle speed 1000revs for example.thanks for any info.
Title: Re: CO readings?
Post by: G40supercharged on February 21, 2009, 08:17:22 pm
The CO pot is a variable resistor which sends a signal back to the ECU to fine tune the CO level at idle. It's unlikely to be causing the idle problems you have though. Check with a multimeter set to resistance with the engine OFF. A value of somewhere round 500 ohms shows its not broken. There isn't a particular value it should have; it's an adjustment you make when you have a CO meter on the exhaust. If it's reading a reasonable value I would leave it alone.

Is the problem when the car is cold or is it still there when fully warmed up?
Title: Re: CO readings?
Post by: GAF2 on February 21, 2009, 09:10:31 pm
It doesnt matter if its hot or cold, it will idle while on choke but when it should drop to 1000rpm and hold it just keeps dropping untill it gets so low it stalls????  People have suggested the idle air control valve under the inlet manifold? can this be removed with the manifols still in place??

cheers
Title: Re: CO readings?
Post by: hayesey on February 21, 2009, 09:18:05 pm
it's a struggle to get to it without taking the manifold off (but no it's not impossible) and it's easy to take the manifold off so I'd just do that.
Title: Re: CO readings?
Post by: GAF2 on February 21, 2009, 09:48:04 pm
cheers guys i guess i know what am doing with my sunday now, fingers crossed for now for good weather.
Title: Re: CO readings?
Post by: hayesey on February 21, 2009, 11:43:36 pm
me too! supposed to be taking the gearbox off a corrado vr6.