Ive recently bought a onyx firecat kitcar which uses all mk1 uno running gear.

Only had it two weeks and it's been fine. Taxed it yesterday and proceeded to take it out on its maiden voyage and this is when the problem started.

It's sputtering, almost like its firing on three and kicking out black smoke.

Anyone experienced the same problem or might know what it is?

any help would be greatly appreciated.

Hugh

Jammed-open airflow meter flap? Perhaps the unique installation has caused oily residue to run down to the airflow meter and maybe it just needs a clean?

Or maybe throttle position switch stuck in the 'full throttle' position, causing the ECU to tweak up the mixture strength.

Or, fuel pressure regulator busted diaphragm, or kinked return line to tank causing excess fuel pressure?

I remember reading about these Firecat things using the FIRE engine (hence the name) - the Uno Turbo engine is quite different but they have figured out a way to fit it, then?

-Alex

As per your other Thread on the same subject.

Try the easy / cheap bits first.

Spark plugs first, then spark plug leads in my opinion. Does it have any service history? If not give it a good service, oil, filter, airfilter & some fresh coolant mixture. If it still mis-behaves you know it's not the obvious that way.

Next I'd look at timing / fuelling, but those symptoms can come from a dodgy coolant temperature sensor, making the ECU think the engine is cold & over-fuelling it, like having the choke out on an older car...

Thanks for your help guys.

I've fixed it now, turns out the return fuel pipe was blocked.

The onyx is a cracking little car and great fun to drive, it's about the same weight as a bathtub so it's goes like hell..

cheers..John