C20LET Fault 21 and idle at 1500rpm.

[krobinson]

Well just when I thought I had my Nova running 100%, the ECU light popped back on.

When started from cold it idles perfect at 1k. When it get's close to running temperature the rev's rise to 1.5k.

I've changed both the ICV and TPS for brand new units.

The ECU light flash's out 21 = TPS voltage high fault.

Any ideas folks?

Keith

[krobinson]

I've now checked the loom and it is mint at the TPS. I've had the ecu off the past 6 hours and i've check the terminals. Started and the fault returns, it idles at about 1100rpm on cold, and rises to 1500rpm when it gets warm.

I've noticed that even when my pipes are quite hot, the temperature gauge in the car isnt rising at all, could the temperature sensor be faulty and thus causing a fault?

I'm baffled at the moment.

Keith

[Adam]

Check the small connection on the thermostat housing for the dash gauge.

The sensor the ecu uses for coolant temp is different to the dash one

[krobinson]

I'm baffled really at this stage, Would plugging the car into Tech 1/2 give any better diagnostic than the paperclip trick?

Keith

[krobinson]

Bttt

[Lee]

I would definately tech 2 it Keith!

[Rich]

tech 1 would give you the definate fault code, and you will be able to check what temp/revs the ecu think its at

[krobinson]

I think it may be the wireing to the TPS, I took the tophat cover off and jiggled the wireing about, the rev's shot up to 2-2.5k and back to 1.5k each time I moved the wires. So i'm going to have to strip it back and see what could be causing it.

Maybe its bare and earthing against something causing the high voltage fault? Hopefully its something easy sorted, i hate wireing!!

[mikey14sr]

Might be an intermittant break in one or more of the wires?

[krobinson]

Might be an intermittant break in one or more of the wires?

Fingers crossed thats all it is.