Ok, for a while now I've been having some odd issues with my car, mostly weird cold start ups, and some surging while driving, but it'd go away quickly then the car would be fine for a while. Tonight as I was driving, car started to struggle, wouldn't boost past 5 psi, and threw an unmarked p0101, which as I was aware was a MAF code. I had to check my interceptor to see it, nothing showed up on the dash. After I cleared that out, it went back to boosting again, but then this time was boosting all the way up to 25 psi (I'm GMS1), maybe farther idk I let out, and I've been seeing less vac than normal too, showing up around 18-11 idling in neutral. I assume there's a boost leak involved, but I didn't see anything wrong, though I really don't know what to look for. Ideas?

 

Check your lower charge pipe there is a bolt holding a bracket on that is to long and will poke a hole into it. You will have to look from underneath the car.

 

I couldn't really tell, I can't get under the car far enough to look, I can't jack it up at home.

 

couldnt that be a map sensor or a waste gate issue?

 

Or take your lower and upper map sensors out and make sure they are not covered in oil. You might be able to reach down and under that charge pipe from the top and feel for the hole if it is there. There is a TSB on that charge pipe.

 

ya I was able to get a look at it, I can't really tell if there's a hole there yet or not, but there certainly is an indent.

 

What are your mods?

 

K&N intake, forge bpv, catless dp, GMS1

I'm gonna see if they can squeeze me in to get the car on the lift tomorrow at work. I was hoping to get tuned and dyno this weekend, but if this isn't an easy fix I guess not

 

oh and I should mention once I got off the highway (all this happened in about a 10 min drive on the highway), it went back to boosting normally, stopping around 21-22, and had ~18 vac. Tempermental bastard.

 

That code does generally mean a boost/vac leak. Your best bet would be a boost leak test, but I understand that most people don't have the resources (air compressor/regulator) to run one.

 

ya, nor have I done one before. With the weird levels of Vac that I've been getting that's kinda what I've been guessing, but I wanted to see what everyone else thought. And I'm sure my maf sensor could use cleaning as I've had a K&N drop in on the car since I got it (didn't know it had it till I got an intake), and now have a new K&N Filter, so it wouldn't be all that surprising if there was oil on it.

 

Was out checking around the car some more, definitely something off with it. You could year the DI tick like normal, but every so often it would pick up and tick REALLY fast for a few seconds, and sound like the idle died down a bit. I did the old hold a socket extension up to the motor and listen trick, and you could hear the middle left injector and intake manifold port were FAR louder than the other two. Definitely gonna have the mechanics at work check the car out some more at work.

 

Tommy the symptoms are pretty similar to what my dealer just had to fix on my car. The tang that holds the MF sensor plug in had go broken when they replaced the air filter. I guess not sitting in there really tight was causing inconsistencies reading the MAF? Anyway, they had to replace the plug yesterday and it smoothed the car right out. It was definitely weird. Drove it home Tuesday night it had huge boost and whistled like it had a boost leak. Wednesday morning it was like perma cat warmup, then suddenly limp mode, until I restarted it, then it was down on power then it was fine. Kind of all over the place.

 

^this?

 

Who installed your gms1?

 

Most likely, I've cleaned it once and the upper one is likely covered again, can't really get to the lower one. Need to get a catch can
a dealership local to me, haven't had any issues until recently, had it for over a year and a half.

 

Mines done it twice both times right after leaving speedway in the morning, some of the electrical tape was coming off on the mad sensor on the cold side and it was rubbing the ac lines just something to look at

 

Thanks I'll keep that in mind, I'll be looking at it myself while it's on the lift.

 

take it back to the dealer n tell em the problem while its still under warranty

 

A lot of times the gms1 sensors pull up on the side without a bolt and leak

 

Dealer isn't going to know what to do and the cars not going to act up or throw a code while they have it so they'll give it back saying there's nothing wrong this is a common problem with gms1

 

I work at one, so I got that covered it'll be there 8am tomorrow, unfortunatley so will I for 9 hours

 

What dealer are you at?

 

Stadium GM in salem

 

Ohh I am a tech at toyota in boardman didnt know if you were right up the street at weeny chevy