3sfe idle too high

[GT101]

purchased me a st191 nz assembled 96 corona with a 3sfe for 2g

since ive had the car sits at 1200rpm at idle and ive tried all the usual things like the screw/bolt on the throttlebody etc and checked the fuses , reset the computer.

still cant seem to find out whys its sitting that high

also just did the thermostat and when the temp gets up the fan ins't kicking in.

i thought it was stuck in cold start mode because of the faulty thermostat

anyone got any ideas or had similar issues?

[.:O4AGTZ:.]

Maybe we could swap some idleage, my idles low

[rollaholic]

could be stuck in cold start cos the temp sender is not so good. is your fan getting power?

[XS1V]

For idle high check for vacuum leaks by spraying a can of brake clean or similar around the manifold and intake etc and if it idles up it is sucking it in.

Idle low is normally a setting with either TPS or AFM (if fitted). How low is low though?

Brad

[GT101]

just checked the power going to the fan and theres no power getting to it

and i think the temp sensor is getting none aswell

so i can replace the temp sensor but what about the power to the fan plug problem?

i checked the fuse and it looks ok , spose it could still be faulty?

[XS1V]

There will be no power getting to the fan untill the temp sensor at the radiator tells the relay to switch on the fans. To test the circuit you want to make sure on of the pins to the fan has a constant earth and the other connects to one of the pins on the fan relay in the fusebox. Also make sure the relay is working and there is power getting to the relay. There should be four pins on the relay, one will be 12V with ignition on coming from the fan fuse, one full time power (may be ignition supplied also), one going to the fan plug as mentioned above and the other going to the temp switch on the radiator. If you remove the ground signal on the wire going to the fan switch it should close/click the relay and put power on the wire going to the fan. Hope that makes sense.

The radiator fan sensor will have ground going into it and the other pin will connect to the fan relay with a ground signal at all times until it gets to hot at which time there will be no ground signal to the relay and the fans will come on.

The engine temp sensor should have no power going to it at all. One wire is a full time ground normally from the intake manifold and the other is the signal wire to the ECU.

Brad

[sergei]

There will be no power getting to the fan untill the temp sensor at the radiator tells the relay to switch on the fans. To test the circuit you want to make sure on of the pins to the fan has a constant earth and the other connects to one of the pins on the fan relay in the fusebox. Also make sure the relay is working and there is power getting to the relay. There should be four pins on the relay, one will be 12V with ignition on coming from the fan fuse, one full time power (may be ignition supplied also), one going to the fan plug as mentioned above and the other going to the temp switch on the radiator. If you put a ground on the wire going to the fan switch it should close/click the relay and put power on the wire going to the fan. Hope that makes sense.

The temp sensor should have no power going to it at all. One wire is a full time ground normally from the intake manifold and the other is the signal wire to the ECU.

Brad

I would like to make a correction:

Fan switch relay is always on when there is ignition (you can feel it being hot), it uses "Open when relay ON, Closed when relay OFF" contacts to drive the fan.
When you disconnect the ground from relay coil (what Temp switch does when it reaches certain temperature) the relay turns off and closing the fan contacts.

It is done this way because of failsafe, if temperature switch wire is permanently disconnected the fan will be always on, also to allow pressure switch from A/C system to be in series of the circuit to turn on the fan whenever it disconnects it.

[XS1V]

100% correct as always Have edited above post to include what i missed.

Brad

[GT101]

Sweet cheers for the info once again guys

was just talking to a friend about testing the relay last night.

will give it a go tonight in the shelter of my garage as its getting a tad windy around here.