HELP !!!!!

[AndyTiv]

I''ve just driven home from the pub in my Chimaera 450 (sobre of course) and half way home it started jerking as if it was about to run out of petrol. I stopped the car waited 5 mins and drove off again. One minute down the road the same again. Feels like fuel starvation. I managed to limp home on what seemed like 50hp. Any ideas before I call out the RAC on Saturday morning. By the way, I filled the tank up with super unleaded only 10 miles previous. AndyTiv

[Graham-S]

You don't say how old the car is. I had a similar problem with a low mileage S2 a few years ago. After numerous visits to Interpro rolling road etc etc and £100's wasted on re-tunes and new leads, coil etc etc a classic bike enthusiast told me to check inside the petrol tank. The previous owner had always stored the car through the winters, but with next to no petrol in the tank. Result= one large headspace in the tank filled with moist air which was causing the tank to shed fine rust particles. The rust sludge settled at the bottom of the tank and the engine jerking/fuel starvation only occurred after the tank contents had been stirred up around fast bends. Getting a new tank was a different story......(before Steve Reid could supply them)

[bryanlister]

Seems like a good suggestion. Something else that can cause these symptoms is a clogged breathing hole on the petrol filler cap. Never heard of this on a Chimp but I have seen this happen with other cars. If the 'pin' hole on the filler gets clogged, air struggles to get into the petrol tank i.e. a partial vacuum is created. I could be wrong, but maybe worth checking as it is a 2 minute job. Just clean up the cap with some methys and unclog the hole with a piece of wire.