My 2000 ES has had a high or erratic idle since I purchased it. When you start the car it jumps up to about 1500 RPM and stays there until it warms up and then it drops down to about 1000RPM. Sometimes when you start it the idle will surge up and down. When you put it in gear it steadies out. I’ve checked the IAC and it is OK. I’ve checked for a vacuum leak and found nothing. Before I pull the intake manifold off to check and see if it’s cracked I thought I’d check the throttle position sensor and the oxygen sensors. The problem is the TPS costs $60 and you can’t return it. My question is ‘can the TPS or the O2 sensors be bad be bad without throwing a code?’ I’m not getting any codes at all from the car.

 

I had a high idle problem with my 05 sxt. it turns out the throttle body hose that connects the throttle body to the intake had came lose and was letting fuel escape. I think the engine heat caused it to get soft and while it was soft i ran it hard and it came off. check that.

 

So the TPS is $60

Depending on how many miles it has, by my logic these sensors are going to need to be replaced if you're over the 100,000 mile marker.

I know the 02 sensor will throw a code once it's completely gone