engine running rough

[Chris@Nitron]

Hi guys, i have just rebuilt a caterham superlight R with a slightly modified k-series engine.
when i start the car it doesnt like to idle very well and when the revs are increased it seems a lot smoother, i tried to drive it up and down the road, but the engine didnt being under load, when i floored it, it felt as if the engine had a limiter because it was missing so much.
ive been through the wiring, but cant think what the problem might, any help would be much appretiated.
Thanks Chris

[dutchy]

Chris,

I've been having very similar problems with my SLR!

I may have fixed it but I'm not saying for definite as I thought I had before.

Things to check :-

1. All earths from battery ( both ends), clean them up and the one engine to chasis.
2. Check your TPS and check resistance as per MinisterPower.
3. Check the temp sensor (brown one) is working, disconnect and fan should cut in.
4. Air temp sensor, I had a spare to swap round.
5. Battery voltage, and also if its charging
6. Fuses (this may have been fault with mine), under dash clean up or replace ECU and Fuel pump fuses. Mine were very oily and had been arcing creating higher resistance.

There were a few other things such as throttle body settings and leak down tests but check the others first.

Good Luck

Steve