MG ZR 1.4 'pinking'??

[daemon]

My son has an MG ZR and its 'pinking' quite badly, to the point whereby its quite undriveable.

I had the car to my mechanic yesterday and they replaced the plugs, no change, so they replaced both coil packs. That seemed to cure the problem, but today the problem is back.

No water in the oil, and no oil in the water and the engine otherwise seems fine.

Anyone got any ideas?

[Mr2Mike]

Are you absolutely sure the car is pinking and you aren't hearing e.g. an exhaust leak between the manifold and rest of the system?

If so has the head gasket been replaced in the cars history? It's possible to skim too much off the head and raise the CR enough to cause pinking.

[daemon]

Mr2Mike said:

Are you absolutely sure the car is pinking and you aren't hearing e.g. an exhaust leak between the manifold and rest of the system?

If so has the head gasket been replaced in the cars history? It's possible to skim too much off the head and raise the CR enough to cause pinking.

No, its definitely pinking.

Car had been running fine since we got it three months ago. just started doing this...

[tuscan66]

naff fuel ??? try an additive and some high oct top up worth a go

[alfa pint]

Take it to a cheap garage and have the fault codes read. If it's pinking, then there's an issue with the timing which is due to something like the ecu playing up, the dizzy having issues, fuel not being right etc etc. The problem with new cars is the variety of things that can go wrong, but at least they tell you what it is!

[mgmrw]

The plugs you had dropped in, they the "platinum" jobbies? or just normal ones?

Know mine used to have to have specific ones.