HELP!

I have changed Knock Sensor (as per fault code)

I then changed Lambda Sensor (as per fault code)

Then no codes showing but running really rough on idle, flat spotting, and stalling sometimes...

So then changed MAF as a precaution...

Now reading Lambda fault again??? and running really rough?

Any ideas...

 

Take it to a speciallist/dealer, their diagnostic kit will point to any other issues and a mechanic will probably find the fault and save (too late) you a fortune in sensors.
Apart from that, there are too many other things you have not mentioned, last service, when was the air filter changed? is it only doing this when cold or all the time?

Tony

 

It had a full major service a week ago, everything...

This happens all the time particularly when warming/warmed up...

Might have to take to main dealer...but would rather not!

 

Idle control valve possably, coolant temp sensor though this would normally stop when the car is warmed up...

Tony

 

Do you have an atmospheric dump valve fitted?

Cheers Iain

 

Sounds like specialist advice is what you need. The obvious thing to check would be whether the sensor ground has come loose. This is a thick black cable that (should be) bolted to the inlet manifold next to the nearside intercooler mounting bracket. 12mm hex head bolt - make sure it's tight and that the cable hasn't fractured where it is connected to the eyelet.

Comment above re. atmospheric dump valve worth checking too. If you have the standard dumpvalve fitted, would be worth taking it off and seeing whether the spring has lost its temper (i.e. the valve doesn't snap closed).

 

Cheers chaps i will check that in the morning and post the result, I cant say the cable is even something obvious i have seen.