Hello, can anyone help please!
On friday my car (95-classic) started idling at 1500rpm and the CEL came on, as soon as I touch the throttle it goes out but when the engine speed falls back to 1500rpm it comes back on. The fault code it is comming up with is no.42 idle switch. I have changed the throttle body with TPS attached (to avoid adjusting the TPS) with a spare one I had and reset the ECU, but it has not solved the problem. I have checked the voltages at the ECU and I am getting 0v with the throttle closed and 4.8v with the throttle open, so everything seem to be as it should. Other than this the car is running fine and idling smooth all be it at 1500rpm
has anyone came across this before or does anyone know what else would cause a no.42 idle switch fault to come up.

Cheers, Jonjoe.

 

has anyone got any ideas, this is really doing my head in!!!

 

fault code 42 reccomends to check the following
check input signal for ecm - ok = repair ecm connector terminal/replace ecm.
check harness connector between ecm & idle switch - not ok = repair or replace harness connector.
check & adjust idle switch - not ok = replace throttle position senor.
hope this helps mate.

 

Cheers scooby tech, i've checked continuity of the loom from the ecm to the switch with a multimeter and that appeares to be ok. i've checked the voltages at the ecm and i'm getting 0v with the throttle closed and 4.8v with the throttle open which according to what i read is ok. is there any other sensor that might indirectly cause a 42 fault code.

thanks for your help!