Hoping someone maybe able to point me in the right direction tracking down an issue

Vehicle had an engine service last week, oil change, oil filter/air filter, new plugs and leads, running on 99octane tesco's fuel, vehicle is a 99 Xantia Activa Petrol Turbo

No warning lights on dash

When below 3000rpm the car has a very very slight hesitancy, like a very light misfire or slight pinking, in every gear (except 1st as it appears to be too low, ratio wise) it doesnt really want to take full throttle, so its a case of nursing it to 3000rpm, then flooring it

Above 3000rpm it boosts as it should

The car is totally standard

Any suggestions would be appreciated

Thanks

Hi ukactiva,

No turbo pressure ! Check air filter/intercooler for blockage and tubing/ducting down stream of turbo for leaks.

cheers

noz

Thanks for the response

Just so that I can fully understand this, it would be low turbo pressure, ie a leak

How come it would boost above 3K though ?

Would it be that the leak is so small (for now) that the turbo boosting would overcome the leak ?

I have had a quick look at the intake system and the tubes take quite a nice circuit of the engine bay, none of which seem very easy to access either, so I think I should book it in to my local performance car tuner for them to trace

Hi ukactiva,

My Activa was very sensitive to the type of plugs fitted. It hated Bosch, Unipart, NGK and Delco and gave the symptoms you describe.

I even thought I was doing the right thing by upgrading to NGK iridiums but it hated them too. Problems went away when I put new cheap-as-chips standard champions back in.

It also didn't like the performance (magnecore) silicone HT leads I bought for it either (misfire at low rpm - <2500) so I had to put the originals back on.

Given that all the plugs were brand new and the correct heat rating, my engineering brain cannot explain this anomoly.

Just one more pleasure of owning such a different and under-rated car (Activa) that retains the idiosyncracies of citroens that we all seem to view as a challenge rather than negative

I took your advice ref plugs, as I did purchase bosch plus's which were fitted with the service

I swapped back to cheapo NGK's and its running so much better

Thanks for all the advice

It turns out that although fitting cheaper plugs helped the problem, it was the lambda sensor that was at fault

Will be replaced on tuesday and should hopefully be back to normal then