Please help me with my URS4 2,2t -92

[fish]

If i have the gearbox in neutral and try to keep the engine on a steady RPM, let´s say 3000rpm,s it is totally impossible. The engine wanders between 2600rpm-3400rpm, and it is the same on any given rpm. Idle is steady as a rock at 850rpm and there is nothing to be noticed when driving. The car is due it´s MOT soon and part of the swedish MOT test is the CO emissions at 2500rpm. I suppose they will have a hard time doing it with this issue. Anyone got a clue what i should check?

Cheers
Kris.

[UrS4boy]

Throttle position switch/potentiometer and MAF information

For starters, check the pins and their cleanliness (and position) on your mass air flow (MAF) sensor and throttle position switches, as per these two posts:

Throttle switch:

http://forums.quattroworld.com/s4s6/msgs/20405.phtml

Mass Air Flow (MAF) sensor:

http://forums.quattroworld.com/s4s6/msgs/20442.phtml

Might not be them but start there to eliminate the "usual suspects".

Might also be an air leak in one of your air box to turbo or turbo to throttle body hoses.

[macspring]

urS4boy,

You really are the business, always helping and with great links.

You'll be going straight to heaven. Said in jest, but heartfelt.

Learning loads from the links.

If I was betting fish, I think it'll be the connector connections on the tps, but don't rely on me.

Awaiting the final answer in due course.

Kind regards to you both.

[UrS4boy]

Links to C4 UrS Engine Bay and Chassis Info Maps

You're welcome. I appreciate the positive feedback.

I have posted the links below up before but just as a reminder, there is lots of C4 UrS info (lots of which translates in some form to the S2 and RS2) at these two posts (Remember to scroll down below their diagrams to their respective hyperlinks):

Engine Bay Device Map:
http://forums.quattroworld.com/s4s6/msgs/22625.phtml

C4 UrS Chassis and System Map:
http://forums.quattroworld.com/s4s6/msgs/24724.phtml

[fish]

Cheers mate=)

[prj]

It's 100% not TPS.
Check MAF connector.
Check if ECU has fault codes.

[prj]

Also check ignition, you might be getting misfires.

[fish]

No, it does not feel like missfires, it runs smooth just that it wanders up and down in RPM range. Very wierd.

[prj]

Then definitely check MAF connector and fault codes.

[fish]

It only seems to come up when the car is warmed up... Lambda probe?

[prj]

Vag-com it.
If there is nothing, then start guessing.

[fish]

Not the MAF connection anyway... I´ll get it up on vagcom tomorrow.

[chris]

idle issues?

just had a very similar issue on my 200q with a 3b conversion, having replaced the white 2 pin at the back of the head it may have been the wiring to the sensor, i have re made the connections and all seems good , this is after vag com , no codes, only an highlighted aux air valve connection , but i rec it was adapting the poor 2 pin signal
good luck
chris