Misfire and slow tick-over - help needed!

[S1 Roly]

It was all going so well.... Took the S1 out for a spin today and after stopping for a bit of fuel on the way home, the little git started to misfire. At juncs/r'ndabouts when pulling away in 1st, the revs would die off, before kicking back in again - never known that before! Dipping the clutch as it starts to die seemed to help, as did pulling away in 2nd. Misfired at low revs most of the way home...

Got home and the tick over seems far too low - oil pressure at minimum, and probably turning over only at about 700rpm.

I'm guessing at an ignition problem - so maybe a points and plugs change?

Really not sure, so any suggestions gratefully received.

Best,
Roly

[Jaye R]

Roly

Sparks & plugs always a good place to start - but it could be the old pesky Throttle Pot problem - worth a check??

Cheers
Jaye

[ChrisGadd]

Is it smelling of petrol? if so I'd disconnect the TPS and see if that solves your problem. I had a similar issue when the TPS was giving a fully open throttle reading to the ECU all the time which over fueled the engine on idle and at low speed.

Chris

[Barkychoc]

Did you run the tank very low before you filled up?

You could have pulled some dirt through out of the tank or maybe even you've bought some dodgy fuel - it does happen particularly if the filling station is running low.

[Roy C]

Erm, S1 - so 2.8 & no TPS.

[CTE]

The smallest airleak on the intake side can cause poor running. Check from the air filter housing right through the system to the inlet manifold, all the rubber pipe connections. Use some soapy water.

[GreenV8S]

CTE said:

Use some soapy water.

Better to use a flammable gas such as a cold start spray, or lighter gas.