[Leevan42]

hi guys
got a problem with my 99 corsa 1.2 16v
when accelerating or when the engine is under strain e.g uphill, there is a small rattle after which the eml comes on and ive got reduced power until the eml goes out again.

I will be buying a opcom diagnostic system soon but was wondering if anyone knew about the rattle, sounds a bit like a diesel accelerating lol.

thanks in advance

 

[taurus]

Very hard to say without hearing it. A rattle could be pre-ignition, or worn components (timing chain, valve gear), or a loose engine mount, or exhaust.

It could be something as simple as a dying AFM which is causing too lean a mix, that will cause the pre-ignition rattle and the EML coming on. But that's just a wild guess. You're right to invest in opcom and track it down properly before spending on parts.

(If it is the AFM then don't buy a cheap one, they are useless. It has to be the genuine one.)