Idle issue

[Kyle406]

hello

my 1999 406 doesnt seem to Idle that well. although the engine is in good condition only 57k the idle remains under 1 but the needle jumps up and down to the tune where you can here the engine revs increasing and decreasing but only slightly. the Rev needle never really remains constant when idleing.

any ideas of what may be causing this?

any advice is welcome

thanks

[teamster1975]

I used the search feature and found this thread which should help

[Kyle406]

great information and pics are a bonus. thanks very much

[perils]

Any joy with this Kyle ??

I have like a misfire at idle and sluggish acceleration....
All seems a little better once engine has warmed up.

Just disconnected my Lambda sensor and upon started it nothing appears to have changed.

I'll run the car for a few days without it to see what happens.

I have posted this as "misfiring at idle" in another thread.
The rev counter moves constantly at idle by about 100rpm up and down...


2L D9 GTX 47K miles.

[jasper5]

Clean out the throttle body and the idle compensator valve with carb cleaner.

Also, if yours has an EGR valve, clean that out as well.

If you leave your Lambda sensor disconnected, you will put on the engine management light, if yours has one.

[steve_earwig]

The rev counter moves constantly at idle by about 100rpm up and down...

Ah, if I remember right, that's the engine management winding the mixture up and down, trying to see the right thing from the lambda probe.