ok just like it says. On a normal day my idle is a nice steady 600-700. As soon as theres any moisture outside my idle drops to like 450-500. If i have anything like my headlights or defroster or wipers on it really starts to bog. It has never stalled on me but its annoying. I tried increasing the idle speed with the small screw on the throttle body (the exposed one not the one under the cap) and it worked for about a day untill the ECU figured it out and rest my idle right back to where it was. Any thoughts or suggestions.

 

It's the MAS that actually reads the relatively humidity in the air that it sucks in right? Any mgmt system available to adjust for that?

 

that's really weird. it kind of sounds like the more electrical load you put on the car the lower it idles. have you had your alternator and battery checked out?

 

well heres the thing, it only happens when it raining. The alternator has been replaced, like less then a year ago. How do you tighten the belt that runs the alternator. Maybe that belt is slipping on me when its wet ?

 

You have to get under the alternator and loosen the bottom bolt. Then you can push back the top of it to tighten the belt. I think the bolt that you have to loosen is on the drivers side of the alternator. Make sense?

 

If it makes you feel any better mine has run ****ty on humid days forever.

 

the tensioner is back towards the firewall, the bolt that goes through it and the bolt that attach it to the bracket it is attached to all go through a little square piece... not sure if that makes much sense--but just take a look down there and you should see what i mean.

i do not believe you need to loosen/tighten the pivot bolt to tighten the belt, but if you do it's a 14mm (if i remember correctly) and it's easily accessible from under the car. the pivot bolt is right there under the alternator.