sigma 150 idle speed

[fondelli]

I've just bought my first Caterham after owning 2 elises. I'm a happy owner. I've just had the ECU re-flashed with the latest map that does away with the pipe from the MAP sensor to the inlet manifold.
I've just cranked it up, but the idle speed is too low and it is stalling. Does anyone know how to raise this?

[Nicodema]

tweak the idle screw on the throttle bodies. You're looking to let a touch more air in at min throttle. The throttle stop screws are usually a pair of allen head set screws with anti vibration springs around them, on one side of the throttle cam. Make sure you get the right one (the one that the cam rests against when the tension is removed from the cable) and don't touch the set screw that sets the balance between the two bodies.

edit: I've uploaded an image for you on flickr

Edited by Nicodema on Wednesday 9th June 11:32

[fondelli]

Thanks. I got clarification from the CC workshop manual. Basically TPS voltage reset needs to be done and then the battery needs disconnected for 5 mins to wipe the TPS memory in the ECU (apparently TPS voltage is read at every start up)I just reset the voltage, but did not do the battery disconnect- so my ECU did not do a TPS re-learn. Tonight will tell a story

[fondelli]

It looks like I'm going to adjust the throttle bodies too. I followed the TPS reset procedure and I'm idling at 650rpm hot- which is too low. (should be 950)Do I just crack the throttles open a bit and then do the TPS reset again?

[fondelli]

I'm having posts with myself! I know a guy who runs a race preparation business and he came round and checked the flow rates on the throttle bodies. They were slightly low and out of balance. A few tweeks later and the engine is running as sweet as a nut.

[Nicodema]

Nice one! It always helps having an expert right there, hands on, rather than an enthuistic amateur making guesses over the internet.