Cannot holds revs

[ess_four]

Guys,

My 2003 B6 is having problems getting through the UK fast idle smog test. The car is revved up to 2500 has to be held at this rpm for 30s. The problem is that the revs keep on climbing beyond 2500 and if you try and modulate the throttle all revs drop off.

The car has deleted pre-cats and 100 cell sports cats. It also throws the following codes on a regular basis:


17522 - Oxygen (Lambda) Sensor; B1 S2: Internal Resistance too High
P1114 - 008 - Implausible Signal

16524 - Oxygen (Lambda) Sensor B1 S2: No Activity
P0140 - 004 - No Signal/Communication


The sensors themselves were replaced due to the same set of codes but did not make any difference. In summary does anyone have any ideas how ot maintain revs or is the problem related to the codes.

[SprintBlueWorld]

Possible maf trouble or maybe a clogged cat. Thats the eldest of b6's!

Something throwing of the ecu logorythim. Ive heard a bad pcv can have an affect as well. Check all air hoses verify seating and that there are no leaks. If no help then I'd go through all the air sensor connections and reseat.

[MidwestB6]

Are you tuned?

[jakeoboy67]

with my car (stock tune) , I just cannot hold a certain rpm, the accelerator pedal becomes to sensitive. a bit less throttle= comes back to idle a bit more throttle= rev a bit too high

[blai76]

with my car (stock tune) , I just cannot hold a certain rpm, the accelerator pedal becomes to sensitive. a bit less throttle= comes back to idle a bit more throttle= rev a bit too high

Piggies, JHM 91, milltek catback, tiptronic here. No problems holding RPM at any RPM.

[ess_four]

Possible maf trouble or maybe a clogged cat. Thats the eldest of b6's!

Something throwing of the ecu logorythim. Ive heard a bad pcv can have an affect as well. Check all air hoses verify seating and that there are no leaks. If no help then I'd go through all the air sensor connections and reseat.

Thanks guys for the responses. The car is tuned, MAF is within tolerance and the PCV was changed a few weeks back. I'll check the hoses for leaks. I'm inclined ot think that the cat(s) has given up the ghost but would like to rule out any obvious causes.

[madkimchi]

Thanks guys for the responses. The car is tuned, MAF is within tolerance and the PCV was changed a few weeks back. I'll check the hoses for leaks. I'm inclined ot think that the cat(s) has given up the ghost but would like to rule out any obvious causes.

It could be your tune. What kind do you have? Just on this board many people with certain tune have same issue. Cannot hold that 2500rpm. I Think it's all unitronic tune that's causing it but I m not 100% sure.

[ess_four]

It could be your tune. What kind do you have? Just on this board many people with certain tune have same issue. Cannot hold that 2500rpm. I Think it's all unitronic tune that's causing it but I m not 100% sure.

UPDATE: Tried holding 2500rpm again and all was well for a few seconds until they started to rise slightly and then all revs dropped off. It was like a trip switch being triggered. Checking for leaks later as well as disconnecting the MAF

[ess_four]

It looks like the MAF is the root cause. Reset the TB and still could not hold any revs. Disconnected the MAF and was able to hold revs.