Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Christopher doc on 05 September 2008, 14:02:37

Title: Revs won't stay where I put them on 2.5TD
Post by: Christopher doc on 05 September 2008, 14:02:37

Any help on weird accelerator problem would be welcomed. I have a facelift cdx 2.5td with the BMW inside. I am getting some uneven power at slow speeds around 1000rpm in 2nd or 3rd - when idling along in yet another motorway queueueue.http://images.omegaowners.com/forum/yabbfiles22/Templates/Forum/default/angry.gif It shows as a power judder. Accelerate a bit and all is fine.
I was idley musing over this and tried slowly pushing the accelerator down - whilst parked this is. Revs went up a bit and then shot up to nearly 2000. Slowly letting the accelerator up and the reverse happened - sudden drop in revs. I could not get it to stay steady at between about 900 and 1600rpm.
Any ideas? Is my engine management thingy f****d or could it be anything cheaper.http://images.omegaowners.com/forum/yabbfiles22/Templates/Forum/default/thumbsup.gif
I just joined your forum and love it already. So much good stuff
Cheers Christopher

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: The Barge Captain on 05 September 2008, 14:19:34

It's very important on an Omega to keep all your revs under the bonnet ;D

Seriously though it sounds like you have an air leak somewhere.  Probably hard to hear over the noise of that oil burner though :y

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: osealy on 05 September 2008, 14:35:29

Would it be throttle position potentiometer.

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: Seth on 05 September 2008, 16:41:06

Quote

Would it be throttle position potentiometer.

I'm pretty sure this is within the injection pump and would mean shelling out mega bucks.
Start by changing the fuel filter, and filling with Forte or Diesel Magic.
Run it for a day or two, and see if this does the trick.
While you're at it, check the wiring and connector on No.4 injector, as this has a 'start of injection' sensor within it, and communicates with the injection pump and ECU. The connector is below the inlet manifold - just follow the wire downwards from this injector.

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: Andy B on 05 September 2008, 18:22:59

Quote

Quote

Would it be throttle position potentiometer.

I'm pretty sure this is within the injection pump and would mean shelling out mega bucks.
Start by changing the fuel filter, and filling with Forte or Diesel Magic.
Run it for a day or two, and see if this does the trick.
While you're at it, check the wiring and connector on No.4 injector, as this has a 'start of injection' sensor within it, and communicates with the injection pump and ECU. The connector is below the inlet manifold - just follow the wire downwards from this injector.

There's another on the accelerator though ...... could be that end

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: Omegatoy on 05 September 2008, 20:29:15

firstly does the eml come on when it does it and secondly have you read any codes that may be stored?

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: Christopher doc on 05 September 2008, 21:16:14

Thanks - I will check the cheap things first when I get a space!

In answer to some of your questions - no the eml light never comes on when running and I did the paper clip test and got no fault codes out

Any idea how to get to the potentiometer at the accelerator end?

Ta

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: TheBoy on 07 September 2008, 18:28:44

So does eml come on with ign then?  If not, put the bulb back in!

Title: Re: Revs won't stay where I put them on 2.5TD
Post by: Christopher doc on 07 September 2008, 19:58:42

Quote

So does eml come on with ign then?  If not, put the bulb back in!

It works then, just fine.