un burnt fuel would mean a spark issue which would also cause your bad idol.

couple of things this could be -

Bad wiring in your coil pack loom - well known to go.

Coil pack failier.

Leads.

Could even be as easy as shite spark plugs bud...

do us a favour, go out and unplug your lambda's for me, see how it runs now???

Feel free to add me on MSN if you need quicker responces -

minirotty@hotmail.co.uk