Shortbus

First off heres the info on the car

2008 cobalt ss/tc
8,000 miles
k&n sri
zzp catless d/p
stock tune




heres the issue

Just recently i have been having a issue with boost, No CEL, and no codes on the car. When i first put the sri on the car it ran fine, bpv sounded like it was opening and closing properly. Now weeks later it is sounding like the bpv is not working properly, it will spool but not make a lot of boost, 10-12 psi MAX. This usually happens when the car is warmed up also, doesnt do it around 100* but around normal driving temps. To me it sounds like the bpv is opening when it shouldn't be. I would like to get this figured out before i do the zfr and other mods. Any ideas? Maybe the car doesnt like the k&n on stock tune?

AARON-SS-TC

iTrader: (3)

wait a minute, you have 8,000 miles on your car? damn...lol

Shortbus

Haha yea, lucky find. It's pretty much brand new.

Shortbus

Problem solved, cleaned maf and changed the position of the k&n filter.

AARON-SS-TC

iTrader: (3)

Scooooooore...with 8k miles, i couldnt imagine anything major wrong with it

Shortbus

Same thing I was thinking, the first 6k of this car were babied by a old guy.

Terminator2

And you know he never tuned or modded the car more than likely. What a find I want another SS/TC but I want a sedan this time.

Shortbus

Very lucky find sir!

Problem is back, turbo just makes a whistle sound, low boost. Bpv is not functioning I believe, but still no CEL wtf!

rukkee

iTrader: (3)

I had a similar problem when mine was new .... ended up being the wastegate actuator had a bad connection . Plugged the connector in all the way and was good to go.

Shortbus

Hm, ill have to check it out. Thanks!

Terminator2

Check for leaks. It takes a big leak to trigger a rich code or MAF out of range code.

Shortbus

Ill check, the weird thing is yesterday it ran fine, then the next low boost again. Wouldn't a leak be constant?

Maccoy316

iTrader: (1)

I had the same problem even with a Forge BPV. New tune and cleaned the MAF sensor and it's good to go. Haven't had the problem in a long time.

Shortbus

The other day, I changed the position of the k&n filter and cleaned maf. That worked for a little while then it went back to doing it, still does it on my new tune i got yesterday, no changes from stock tune to new tune.

Terminator2

Check the WG rod but you have to get under the car to check it. Check BPV diaphram to make sure it is not ripped.

Shortbus

Thanks, ill check them!

Shortbus

Now randomly runs fine again, bpv working wtf!? Then when it gets to operating temp same crap, low boost bpv not working.

BaDAssCoBalt08

have you taken it to the dealer or a professional yet?

alerosaint

These cars have the weirdest intermittent issues! Smh... I have a similar problem.. My car sometimes dump boost randomly a one minute
And pulls fine to 26 psi the next

Shortbus

Same thing it's doing, I'm getting frustrated at this point! Currently have the car in the air.

Shortbus

Not taking it to a dealer.

Terminator2

Could be a dirty boost solenoid or in the case of a car running 26 psi p0106 or other boost related code may not be disabled in the tune.

alerosaint

Funny thing like shortbus, I am not getting a code. I would WOT in 3rd 26 psi shift, then wot in 4th and get 20psi......try it again get 26 psi in 3rd, shift then get 26 psi in 4th. I am getting ready to throw a boost solenoid at it. P0106 is enabled tho

Terminator2

Turn p0106 off and see if it stops. If not clean the boost solenoid out with carb cleaner and check the plug as well.

Shortbus

Where exactly is the solenoid located?