Hi Guys,

I've been having a problem with my 1999 Octy 1.8i 20v for a couple of months and cant quite track the problem down. I thought someone here might be able to help.

I took the car to a local garage for an MOT, no service, and when we got it back the car was running really rough when first started. We had it back to them and they replaced the "check valve" and it run a lot better but the power still fluctuates when first started for the day.

The same problem seems to occur when cruising on the motorway when the power just drops off. The problem goes away when you lift off the gas.

By the look of the spark plugs the car is over fuelling.

Had it into a Dealer for diagnostic and no fault codes. Also I ran through fuel and injector cleaner, but the problem is still here.

I've searched some of the forums and the only similar things I have found is faulty MAF units. If i'm right the 1.8 20v has two sensors, one on the air intake and one on the throttle body. Is it worth replacing both of the sensors?

Any ideas greatly received.

:iagree:

To double-check, pull the wiring connector. If the car goes onto the default map and runs better, you need a new MAF.

Thanks, I pulled the MAF wire yesterday and the car seemed better until pulling away from a roundabout when the power was lost again.

Will replace it and see how I get on.