Ok, I just replaced the clutch on our 02 Elantra and now it won't idle. It constantly fluctuates from 1200 to 3000 rpm every 2-3 seconds. I've unplugged the throttle position sensor and the idle control valve, and neither effected it, except for lowering the rpm overall.

While detaching the transaxle from the engine, I mistakingly removed the two small diameter, but very long, screws directly on the bottom of the bellhousing, thinking they would need to come out. Do these have anything to do with the crank position sensor? I'm imagining now that they hold part of it in place or something. Have I screwed up? and how bad? If it is the crank position sensor that is likely causing this new headache, can anyone give me some detailed instructions on how to adjust it?

Other than the engine not running correctly now, everything else came out fine, lol!

 

Those bolts are for oil pan. Nothing there. Now when you did the clutch did you replace flywheel with a aftermarket? Have seen incorrect flywheel do this. Other then that maybe you made vacuum leak by dropping engine too far down. Pulled a vacuum hose ...air flow boot not on all the way...ck grounds? Alot of things can do this. Retrace your steps.

 

Turns out, when I dropped the engine to gain working room between the block and tranny to get the clutch out/in the cruise control cable connected to the throttle body got yanked about 3mm. The only visible evidence of this was that upon VERY close inspection you could see a bit of shiny new cable sheathing exposed where it exits the cruise control actuator (again about 3mm, less than a 1/4 inch). This in turn was putting the slightest pressure on the throttle body butterfly. Even though it appeared fully closed, it lacked maybe one degree of rotation from being fully seated. The extra air apparently threw the engine into a paranormal state, lol.

A real quick adjustment of the cable tension alleviated the problem and the car drives great now.