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Re: rattling engine sounds

What is the octane rating of your petrol?

I find that my '95 Mondeo glx performs poorly on our (Australian) standard unleaded petrol mixture, with quite a bit of rattling evident under light engine loads or very heavy acceleration.

A quick and easy fix has been to use high octane petrol - one side effect is better fuel economy.

Two local dealers agree that the engine is 'pinging' but are unsure what the remedy is (have already reset and tested CPU, replaced MAP sensor).

Hope this helps,

Cheers.