Air Mass Meter Disconnected

[Graham 70]

I have been trying to cure a misfire under load. I have replaced all usual parts and have discovered that if I disconnect air mass meter connector, car runs fine. Can I assume meter is faulty and can I do any harm driving car while connected? Thanks.

[Crasher]

Have you had a fault code read done? What are the “usual parts” as the first usual part is the AMM? What is the engine code and year?

[Graham 70]

Hi, 1998 AGG Engine. I have replaced rotor,cap,leads,plugs,fuel filter. Garage had 2 fault codes; Coil pack,Lamda sensor, Both replaced. AMM was inside allowed parameters, Thanks

[Crasher]

They can’t have read a coil peak fault code, the AGG engine ECU doesn’t support coil pack fault code abilities. AMM failure on the AGG is extremely rare, they are very reliable units. Disconnecting the AMM is showing you that altering the fuelling and stopping the misfire which is probably overfuelling. It would be interesting to see some lambda sensor voltage figures, I have seen the front pipe gaskets leak and cause the lambda sensor to think the engine is running lean and start adding too much fuel.