Newbie - rough running problem

[TVR+Bubblecar]

Recently got the car I always wanted - "w" chimaera 450 with 14k on the clock.

I now have the two extremes - 285bhp TVR and a 10bhp Messerschmitt bubble car !!

The Chim is great but it doesn't like running under 2000 rpm - it hesitates and seems like it is misfiring - it also smells rich if that makes sense - overfuelling ?. The problem is worst when it get up to normal temp - 90 ish. If I drive it hard no problem !!!

I have ordered the bible but looking through the archives I can see references to Stepper motor and SNB802 as favourite problems

Could someone explain what each does

many thanks
Chris

[Li'l pugs]

Without my Bible to hand, don't know what the SNB802 is, but can deff recommend cleaning the stepper motor as a starting point. Should only take 10 minutes and does the world of good !

[glynlucas]

The SNB802 measures the temperature of the engine coolant as it circulates the engine. It sits to the right of the Plenum (looking from the front) and has a single connector. It's nothing special, just a thermistor. However, they are prone to failure becuase of the high temperature of the Chim' engine bay. You can obtain a replacement from TVR for about £15.00 or order directly from a good motor factor for about £8.00. As the Bible points out, at that price, they are one of the parts that you can afford to replace just to see if it helps.

If you suspect over fueling is an issue, I think you are certainly looking at the two most likely suspects. When I bought my Chim' I began to think I would need to get used to lumpy lowend running. However, with careful setting, cleaning of the stepper and replacement of the temp sensor, it is now as smooth as any other car I've driven!

[TVR+Bubblecar]

Thanks for the info

Will sort it at the weekend if I can stop driving the car !!!

Chris