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my car idles really wierd. It goes up and down. Up and down. All the time even after it is warmed up. It will climb to about 3k and drop down to almost stalling.

I'm thinking I got a bad sensor somehwere but don't know which one. Please help.

reset your tps. check for vacuum leaks.

Have a read of this current thread;
http://www.mx-3.com/phpbb2/viewtopic.ph ... 368#314368

thanks for the info. Looks like my sunday is filled up now. LOL.

I just realized something. My car idles fine when the shifter is set in neutral. It goes into wierd mode when I put the tranny into gear no matter whether the clutch is engaged or not.


It seems like a vacuum leak would do this. Is there a specific place I should start? My clutch is really worn and I plan on changing it soon.

don't go changing setting (TP sensor )untell you have checked everything else out. try unpluging the idle controll valve first, check for vacum leaks, unpluged connectors. there are lot's of thing's that it could be try the simplest first then work to the harder & more exspensive last. i am sure they are every simular to the probe, but not possitive. if all else read the direction's (online manual) it would be the best thing to do

RodbeyBur wrote:I just realized something. My car idles fine when the shifter is set in neutral. It goes into wierd mode when I put the tranny into gear no matter whether the clutch is engaged or not.
It seems like a vacuum leak would do this. Is there a specific place I should start? My clutch is really worn and I plan on changing it soon.

This puts a whole new slant on things now. Two things to check. First would be the mechanical switch that engages when the clutch is depressed. I remember distinctly that (with old KL08 engine) whenever the clutch was depressed the idle would automatically step up a couple of hundred rpms which I believe would be generated by the ECU. I believe this is an intentional procedure as the ECU is anticipating the car being placed into gear and is basically a slight assist to keep the rpms up to negate any clutch grab and assist in launch when clutch is released. Second, I would check the intake tubing. Since the engine moves when put into gear (albeit) ever so smally, regardless, this may be all that's necessary for the flex tubing to move enough so that air is getting in through a possible crack. A crack anywhere in the ribbed intake tubing will generate a flucuating idle. If unable to find the crack in the ribbed tubing try a procedure that I posted in another thread using a butane lighter refill bottle. Basically spray in even patterns along the ribes of the intake tubing. If at any point the idle starts to surge up, you've found the problem area. Hope this helps.
*John*

I'll try looking for that switch. Any idea where it would be located?


I have a homemade CAI so I will look and see if any problems with the connections.


Thanks for the help.

the clutch switch can be found near the top of the clutch pedal assembly. just follow the pedal up until you see a a little rod attached to the pedal assembly, that slides in and out of a housing when you press or depress the clutch.