Hey Scotty, I have a 1999 Toyota 4Runner Limited 3.4L Auto 4WD with 248,000miles on it. I’ve been having an issue with the idle, it idles at 600rpm when fully warmed and stays there even when the A/C is on. Sometimes when I stop at a light it drops down to 500rpm, but then shoots back up to 600.
The idle causes the interior to vibrate and it’s extremely annoying. I’ve replaced the IAC, Hoses, Coolant temp sensor, Water pump, belts, suspension, upper and lower ball joints, MAF, Spark plugs, Coil packs, TPS, and even adjust the throttle cable. I’m seriously out of things to replace, might I add I replace ALL MY PARTS with OEM Toyota parts. Any idea what it could be?
A classic example of why you should correctly diagnose a problem first, before replacing any parts.
Do you have any trouble codes? Already checked the fuel pressure? Any trouble going up inclines or any hesitation while acceleration?
Watch Scotty’s video - https://youtu.be/-PsP6ZBKZPE
@InThrustWeTrust I cleaned the TB and replaced the gasket that connects to the upper intake manifold. Still idles poorly.
It’s time to take your vehicle to a professional mechanic to diagnose it properly before you spend any more $$$ on new car parts.
Vacuum leak...smoke test. Rotted hose, intake manifold gasket, etc.
@heyinway I just ordered a hose kit for the car, will update and let you know if that helps any. Thanks!
Definitely check the fuel pressure.
@yaser alright I’ll try that and see what pops up!