High idle after ETM clean 2.4 non turbo engine B5422S

[the5ame]

Hi,
every time I start my car from cold it idles at around 1300-1400rpm and doesn't drop for a good few minutes unless I put into gear (don't think its very good for my auto transmission). Before it was all ok until I cleaned my ETM unit, also moved the flap so maybe its lost its basic settings? Scanned it with diagnostic machine and there are no faults. Any ideas?

[Clan]

give it a couple of days to re adapt itself .. But the rpm rising at cold start is normal on later models to heat the catalytic converter quickly , maybe this function was masked with a dirty throttle body ..

[the5ame]

Well I'm not too sure about Volvo's idle at cold but that doesn't sound right, would be nice if someone can confirm the revs speed and for how long it does idle high, my one is 2001 v70. I did gave it a week or few before the post also I did a smoke check on the vacuum system and there no leaks.

[princepugh]

Have you thought about the front lambda sensor? Two things:-

1) It's a heated unit which is supposed to bring it up to temp quickly;
2) The replacement schedule on the early Phase 2s is relatively short.

If the heating element is on it's way out, it could make the sensor slow to give a proper reading, hence the idle, although as you say, no fault codes...

[the5ame]

Originally Posted by princepugh

Have you thought about the front lambda sensor? Two things:-

1) It's a heated unit which is supposed to bring it up to temp quickly;
2) The replacement schedule on the early Phase 2s is relatively short.

If the heating element is on it's way out, it could make the sensor slow to give a proper reading, hence the idle, although as you say, no fault codes...

The lambda has been replaced by previous owner not that long time ago, not sure whats the reason was for that. But I will test it tonight using diagnostic machine to see if it flickers from rich to lean. Also any ides how long it should take before it start to work?

[princepugh]

Afraid I don't know how long it takes but have to assume it's very quick as thats what the element is for.

Just had another thought too - as you've cleaned the ETM you may wish to reset the throttle pedal - do a search on here, believe there's a procedure you can follow to re-calibrate the fly-by-wire throttle, gotta be worth a try also.

[the5ame]

Originally Posted by princepugh

Afraid I don't know how long it takes but have to assume it's very quick as thats what the element is for.

Just had another thought too - as you've cleaned the ETM you may wish to reset the throttle pedal - do a search on here, believe there's a procedure you can follow to re-calibrate the fly-by-wire throttle, gotta be worth a try also.

I believe thats what my problem is, as on most cars when you clean throttle body it needs basic settings reset.I've looked all over this and other forums but could not find the answer how. Also I don't think the lambda sensor or anything else will go wrong after throttle body clean.

[princepugh]

The calibration process I was thinking of is referred to in this thread: http://www.volvoforums.org.uk/showth...ht=calibration

You're probably right about the Lambda sensor, was just thinking that it may have been masked before you cleaned the ETM.

[mattyfezf]

can you reset the ecu by disconecting the battery for ten mins or so?

[the5ame]

Originally Posted by mattyfezf

can you reset the ecu by disconecting the battery for ten mins or so?

I did that already. I did follow princepugh advice as per link, but hasn't done the trick. In some other post I found that I might need to leave ignition on for 10 minutes and the restart it, will try that tomorrow. Thank you everyone for information will keep you updated so someone else might get use out of this.