Vauxhall Omega Diesel - viper911
Anyone know what causes my Omega 2.5 TD bmw engine not to rev smoothly. If i try to hold it at a steady speed in nuetral it rev up and down. Also the tickover will suddenly jump to 1500 rpm instead of running smoothly at 500rpm, a real problem with an automatic

Vauxhall Omega Diesel - Fullchat
The engine is \"fly by wire\" ie no throttle cable. It has a potentiometer which can get a bit dirty. Dont ask me where it is this is third hand.
However it could be the Air Mass meter which is situated above the air filter. They will clean but only with extremely delicate treatment.
Could also be an air leak somewhere in the induction system and the ECU is trying to compensate.
May need a trip to Vauxhall dealer for a \'tech test\' where they plug in their eqiupment and read the ECU.
Had a minor problem with occasional rough running at tickover on my Omega TD. Tech test diagnosed a possible fault with Air Mass meter. Replaced at £120 and no difference. So if it is your Air Mass meter I have a good one. ( Although I sold the car a year ago!)
Vauxhall Omega Diesel - viper911
Thanks for the info i will try to find out where the potentiometer is and clean it. Unfortunately Haynes dont do a manual for the diesel and i cant find anything on the net, so if all else fails i will have to let Vauxhall rip me off.

Thanks again
Vauxhall Omega Diesel - Vin {P}
Someone on this site (I've tried to search for it, and failed) posted a website that gives a guide to fooling the ecu into giving up its information. Basically, you connect different points on the diagnostic port and watch for flashing lights on the console that tell you the fault.

Unfortunately, I didn't bookmark the site, so if anyone else knows how to find it, I'd appreciate it as well. (I was going to let my local independent in on the details).

Vauxhall Omega Diesel - smokie
Vin - I think this is the post

and this is the website link

but unfortunately it seems to be no more. Might be worth checking in a week to see if it's popped up again.

However, this one looks similar - could a tech please confirm it is right before soeone uses it?
Vauxhall Omega Diesel - Dynamic Dave
but unfortunately it seems to be no more.

If you goto his homepage you'll see the reason why.


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