03 g35 sedan 5 at.... p0102 code..cleaned MAF checks everything. Does it when it rains. No I do not have aftermarket intake, and no the MAF is not getting wet by what I can see. Any help would be appreciated please! I have been attacking this for a few days now. When its dry and sunny out it runs fine the CEL does not come on at all. When it rains, not even a heavy rain, just rain..... CEL (p0102) VDC and SLIP and limp mode. I am at a loss

 

Usually, when issues arise during rain storms, it can sometimes be caused by bad/corroded wiring or nicked insulation or wiring shorts to ground and such. The wet rain plays havoc with the wiring. Hard to troubleshoot short of having wiring diagrams and going through the harness tracing it all out.

Was the car ever in an accident? Does it have a salvage title? If yes, do you know where the hit took place? Just a though, as one of the reasons I tend to discourage buying salvage cars is because sometimes the accident pinches harnesses that do not get replaced, and sometimes you get wiring issues such as this.

 

It was in A smAll Fender bender dont know if it was fromt or back but all body parts are stock so it couldnt have been that bad

 

The dealer doesnt even know what to tell me, this is bullsh!@#! I dont get it I hvae never had such a weird problem. They said the harness checks out no vacuum leaks, he said the MAF looks new, now./.......I am thinking could this be an aftermarket MAF and when it is raining the air is much different than when not raining...could it be throwing it off because it is a piece of crap MAF, as apposed to the $565 MAF from infiniti? Also I have been seriously thinking that it is because water drips down to the IPDM

 

Even though mustang gave you all the ingredients, but you still can't make the potion. Look at each wire leaving the MAF going to the engine harness. It sucks but likely you have a SHORT when it rains because rain does not get into the intake in stock form.

 

and not be noticeable? thats the problem nothing is obvious the only thing that is is the ipdm gets wet, I havent opened it up yet but the outside of the box is definately getting wet, I love this car, but Its getting to the point I am thinking about selling it , I have been wanting a g35 for a while and finally get one and its a nightmare. I cant clear codes manually everytime I get into the car, I just cant

 

Also, just thought of this, (dont know why it would give me a p0102) but.....It first happened after I got two new tires put on it. But because of the stupid inner tire wear I had them put the rear tires on the front and the new on the back. they are cheap champion tires......got it done friday..drove good..saturday sunny...sunday rain all day. That night is when it happened and has happened since when it rains. But it is never on start up from the house, it is after I stop at a gas station or something and crank it again. Could it be the tires/rain?

 

and an oil change a day before that..and thats all that was done

 

I'll suggest you check the IPDM first, it might be causing the VDC and SLIP light too. Check if you got water pooling there.

 

Are those tires the same diameter?

You could be onto something here considering a VDC/slip light comes on

 

Same sizes just the rear are cheap and fronts now are michelins

 

the only difference is the fronts speed rating 94v, and the rear are 93 h....? could that affect it?

 

also, just measured and its i would say right at 3/4" taller in the rear, due to the fronts being worn down

 

There's no way you're going to loose 3/4" in height from worn tires. I think you'd be pushing it to loose 3/4" in circumference. Are front & rear tires the same profile? As in 55, which is stock - 215/55r/17.

 

YEh