Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: omegod on 26 September 2009, 20:56:32

Title: Lambda, where to start?
Post by: omegod on 26 September 2009, 20:56:32
Lambda level is too high and is the last thing preventing my MOT, 1.07 on second fast idle test but should be 1.03 or less.

Whats the best plan of attack to get to the bottom of the problem? there is a split in the ICV pipe would this be a causative factor possibly?
Title: Re: Lambda, where to start?
Post by: rustym95 on 26 September 2009, 21:05:46
would think it would not help, :y is it a fast idle or dose it take it's time? :question
Title: Re: Lambda, where to start?
Post by: lee4206 on 26 September 2009, 21:25:36
What are the co and hc readings as this might give us a bit more of an idea.
If the co is a positive reading then i would had said it was probably a leak in the system somewhere. If its a minus reading then it could be under fueling poss lamda sensor fault or a leak in the inlet system.
lee
Title: Re: Lambda fail, where to start?
Post by: omegod on 28 September 2009, 18:00:42
Sorry for the delay, no electricity for a couple of days!wifes fault!!!

Fast Idle Test   

CO level  0.00% Pass
HC level   48ppm Pass
Lambda   1.11  (fail against 1.03 max)

Second fast idle test

Co         0.00%Pass
Hc level 32ppmPass
Lambda 1.07    ( fail against 1.03 max )


Natural Idle test

CO level 1.01 % (Fail against 0.50 max)

Any help interpreting this into a likely cause would be great, papercllipped the car but no codes stored except 19 Crank sensor  which I know is going to go at some point and will be changed.

Title: Re: Lambda, where to start?
Post by: omegod on 28 September 2009, 20:59:06
Or could the crank sensor somehow be to blame ?
Title: Re: Lambda, where to start?
Post by: rustym95 on 29 September 2009, 07:53:44
I would change both,Lambards do go and they do c=kup. :y
Title: Re: Lambda, where to start?
Post by: Kevin Wood on 29 September 2009, 11:28:02
Well, the crank sensor needs to be replaced ASAP or it will leave you standing so do that anyway.

Any air leak into the induction system will cause errors in the fuelling so repair / replace the ICV hose.

Are there any leaks anywhere in the exhaust system? Manifold gaskets? Pinholes? Joints blowing slightly?

Just because it's failed on the Lambda reading it doesn't mean faulty Lambda sensors.

Is the engine running at the correct temperature (mid-gauge)? Does it come up to temperature quickly (within 1st 2 or 3 miles from a cold start)?

Kevin
Title: Re: Lambda, where to start?
Post by: omegod on 29 September 2009, 19:15:15
Quote
Well, the crank sensor needs to be replaced ASAP or it will leave you standing so do that anyway.

Any air leak into the induction system will cause errors in the fuelling so repair / replace the ICV hose.

Are there any leaks anywhere in the exhaust system? Manifold gaskets? Pinholes? Joints blowing slightly?

Just because it's failed on the Lambda reading it doesn't mean faulty Lambda sensors.

Is the engine running at the correct temperature (mid-gauge)? Does it come up to temperature quickly (within 1st 2 or 3 miles from a cold start)?

Kevin

I have a replacement pipe for the ICV so will replace that at the weekend.

Temp is spot on.

Didn't notice any holes or blows when under it sorting the brake pipes but one joint after the cat is caked in Paste! so there may be a blow somewhere.It is a bit throaty but aren't they all ;D

Guy testing it acknowledged the Lambda level was coming down and at the same stroke mentioned he had been rammed with MOT's so suspect the car was cold when he carried out the Emissions test which never helps does it >:(, cheers for the replies and will keep you posted. :y
Title: Re: Lambda, where to start?
Post by: Kevin Wood on 29 September 2009, 20:34:26
As an aside, as you have LPG mentioned in your profile... If you present the car for the MOT test running on LPG (and make this known) you will get a more lenient test.  :y

Still got a problem to investigate but might ease time pressures?

Kevin
Title: Re: Lambda, where to start?
Post by: omegod on 29 September 2009, 20:40:40
It was set on LPG at the time but doubt that would have been noticed, will check everything and make sure the bugger is hot before it is retested, Cheers Kev :y
Title: Re: Lambda, where to start?
Post by: Kevin Wood on 30 September 2009, 00:05:11
The point is.. If they know it's on LPG and it's presented running on LPG they have to apply lower emissions limits - so if you tell them it might pass. Worth a try.

Kevin
Title: Re: Lambda, where to start?
Post by: eddie on 30 September 2009, 06:37:03
have you blocked of your EGR valve?
 Relevant to the time it takes to warm the Cats up.

eddie
Title: Re: Lambda, where to start?
Post by: Marks DTM Calib on 30 September 2009, 08:19:24
Quote
It was set on LPG at the time but doubt that would have been noticed, will check everything and make sure the bugger is hot before it is retested, Cheers Kev :y

Which sudgests a possible LPG setup issue.....I wonder if your set up has lambda control and if its wired in and setup correctly.

It wont be the lambda sensors I would say as there would be a fault code.