A few times over the last month or so when I give my car some gas. About half throttle or maybe a little more the car just seems to fall flat on its face and not really accelerate . It feels like it very lightly stumbles. I let off the gas and then go back into it and it builds boost fine and acts totally normal. It does it very rarely really. Only seems to be when its raining or the day after a heavy rain fall. Im not sure if that would cause anything to happen. The car is bone stock other then gms1 and an oil catch can. It only has 26,000 miles and runs great and pulls hard normally. Im just wondering if anyone has experienced their lnf fall flat on its face. And then all of a sudden work normal. It seems to build its normal 20-21 psi form the gms1 kit. Any thoughts or advice ?

 

Moisture on the MAF sensor perhaps?
I did have this problem although it was a long time ago so my memory isn't super clear.

 

Its building nearly full boost. But it just falls flat on its face and stumbles. Then the exhaust pops a bunch. Then 30 seconds later it will work totally normal.

 

Could it be spark blow out ?

 

Any other details? Dash light flash at you?
Kind of sounding like misfires to me but that could have a number of causes.

 

No engine light on or flashing... what can cause misfires?

 

start with easy stuff, change plugs, clean maf, ect

 

Could the fuel filter cause it intermittently?

 

Quicksilver, how are your AFRs looking? Lean? A clogged fuel filter/dying fuel pump could cause lean AFRs and hard-starts in the morning.

 

I have no way of checking my afr. So I'm not too sure what they are . But the car on cold starts ups seems totally fine. It really onlys falls on its face during or the day after a rain fall. And even then its only maybe once or twice threw an entire day.

 

I would start by cleaning the MAF before I spend money on replacement parts that I may not need. I have a scanner so I could bring it to a meet and look at your a/f ratio and trims.

 

Check the lower T-MAP. Make sure it's seated properly and also look at the wiring if you can for both the IM T-MAP and the lower. I'd also clean the MAF with the appropriate cleaner as others have suggested.

 

That would be great. It would be good to know whats going on a little more in depth. Also , im about to post my winter tires off my 06 to sell soon so I can pick up your SS/NA wheels for my TC this weekend. Can you pm me your cell number again. My phone is sent out to have a new screen put in it. And I dont have any of my contact numbers anymore. Thanks

 

Its really hard to get a good look at the lower sensor. But it seems to be sitting flush. I think ? I cant really tell all that well ....