Stalling at idle. Anti pollution fault and Code P0170! HELP!

[Ga73]

Hi all,

I had a 51 plate 2.0 petrol automatic 406 (not sure what engine code but told its the later engine as fitted to pug 407 if that helps!) which when I bought it had antipollution fault,

ive bought a code reader which gives me 1 fault of P0170 (fuel trim malfuction bank 1) and the car is very hesitant and also when i STOP at lights etc the engine just dies on me, i cant rev it cos its automatic, if i roll millimeters then it doesnt stall.

Ive changed the air filter, oil , oil filter, spark plugs, cleaned the idle valve which wasnt too dirty anyway but really stuck now as what to do next...

The car is proffesionally converted to LPG but its the same if the LPG is on or just on petrol so i dont think thats an issue.

Apart from checking the air pipes for cracks/splits can anyone give me some tips or advice on what to check next...can any of the sensors cause this fault and if so can they be 'cleaned' or do they have to be replaced.... with Christmas coming up pennies are at a premium so would like to do as much as i can myself, although no mechanic by any means.

Many thanks all.

Gary

[mjb]

First, you should put your location in your profile - if you're anywhere near me, I could plug my PP2000 setup into your car and see the same level of diagnostic information as the dealers can - whick includes the "official" suggested diagnostic routes

I think the only thing from your description that springs to mind to me is a duff idle solenoid (sometimes they can get knackered to the point cleaning doesn't so anything for them)

The antipollution fault *could possibly* cause the ECU to do stupid stuff though. Have you done a search on the forum for "antipollution"? Not dealt with it myself, but I think there's a few common causes and fixes

[Ga73]

Hi thanks for that but would the idle control valve cause an antipollution fault ?

Have searched the forum but no one seems to have the code P0170 registered and im in liverpool by the way!

Thanks

Gary

[HimBigChief]

Have a look here as this guy seems to have had the same problem and cured it. For him, it seems to have been a case of replacing the MAP and then resetting the ECU.