Thread: weird idle

my idle has been very weird latly. it will take a long time to drop down to 900rpms even with the clutch peddle pushed in. it will also randomly sit at anywhere between 900rpms and 1500rpms. any suggestions on what to check. i replaced my tps a few weeks ago and also ive been playing with the throttle cable but its not helping.

clean your IACV. check for cracked vacuum lines.

I have the same problem. My first thought was also IACV. Small hijack: my oil pressure light flickers at idle; checked for oil leaks/burn and found none. Faulty sensor?

Or bad pressure. Check to make sure you have the proper level, and proper weight.

As for the OP, if the IACV doesn't solve your issue, check for vacuum leaks.

I checked the level a few times already, it's fine every morning. As for weight, I went Syntec 10W-30...

definitely not something to bawk at. If that dummy light is flickering, it needs to be figured a.s.a.p. I would not assume bad sensor and just write it off. You could try a different or new sensor, or go with a real-time aftermarket to make sure you know exactly what the psi is, but whatever you do, don't leave that as it is. Too much at stake to just assume it's bad.

I will go real-time, I'm waiting for that tax refund... Until then, what should I do since it is my daily driver. It only flickers at idle, and it goes away once the engine revs up. I heard a faulty sensor at idle could be causing it since the engine wobbles more at idle...

To be honest, drive it as little as possible until you know what's up. You don't want to have to deal with rod knock from something being funky and having low oil pressure. Better safe then sorry.

Considering 2 of my 3 engines got rod knock, I don't take any chance anymore when it comes to my fluids. Last time I got a light for the oil, going around a very sharp corner, I went so far as to turn off the car instantly, pull to the side, and call a friend to bring me a quart of oil. I'm just that paranoid nowadays.

Check TPS adjustment.
Make sure throttle cable is not hanging up and throttle is closing at idle.
Check base idle and timing adjustment.
Clean throttle adjust valve and re-set idle.

When you throw in the clutch with the car moving it is normal for the idle to hang up for a few seconds. This is controlled by the ECU - I think that the ECU is "expecting" you to put the car back in gear and do something so it "reckons" you are going to need some RPMs to do that smoothly. Once the speed drops below 15MPH the ECU lets the engine go to a normal idle. I just mention this to recommend that you evaluate idle issues with the car stopped rather than coasting with the clutch in (if that's what you were doing.)

Also, when you make a change like cleaning the TB or swapping the TPS it takes the ECU a while to learn the change and cut down on the idle excursions. Just something to keep in mind.

Thank you for the heads up. My friends, dad, and I all drove it and checked and the oil was fine when cold, light came on every now and then while idling low, etc. so we all think it's the sensor. My plan right now is to replace the sensor, drive it to check, and see if that solves it. If not, I'll take it to a shop for a diagnostic since I honestly have no clue where to start. I'm thinking if not the sensor maybe the oil pump.