Hello all thanks for looking,

I have an 09 Cobalt ss tc with the following mods.

KN Typhoon SRI
ZZP catless DP
ZZP charge pipes
MPx Intercooler
Brand new motor/turbo(stock)
Trifecta tune

Heres my problem.

I live in Guam and had "chevy" diagnose my car because I wasn't getting full boost and there was a stripped screw on the BPV. I bought a new turbo from ZZP(stock) and asked them to replace it. They did but installed in-correctly. I was told thick white smoke was pouring out as soon as they installed it and would not stop, they told me turbo seals were bad.. Long story short got a new motor and turbo due to cylinder 2/3 leaking(im not good with cars) They finally installed and got it back.. FYI chevy here is NOT chevy in the states.. They have no clue what they are doing. Anyway.. I got the car back... does not boost correctly. I did some troubleshooting, bought the zzp lower charge pipe(plastic one was still on) so I changed it anyway.. No luck. Bought a new BPV solenoid, maf sensor, map sensor(both on manifold and charge pipe), still no luck. Open the BPV and no rips or tears and spring is still good.. Reinstalled all charge pipes and intercooler and tightened all connections with t-bolt clamps.. nothing. Checked for boost leak with tester from modern performance.. Hope I did it right? I hooked the tester to the upper charge pipe and clogged the turbo with a cloth, opened the oil lid like SSlowbalt said.. used a compressed air from the on base car shop and used an attachment used for adding air to tires(it had the white stick with numbers on it) pumped it to 23 psi and it was holding.. no leaks that I could hear and sprayed soapy water and no bubbles... So Idk if I did it right?

After all that, I got trifecta to tune it(during motor swap I had ZZP tune my original ecm with their tune) even with that tune I had no boost.. So I talked with trifecta and they said its a can tune and they dont tweak the small things needed.. So they send me a stock file I data logged and sent it back they revised and said fuel trims were spot on.. Still nothing.. no boost.

So my question is.. Can it be the wastegate actuator? On a new turbo? My motor/turbo has about 2k miles on it. I boost 0 in first gear, maybe 5 psi in 2nd gear, 10-14 in 3rd gear, 4th and 5th ill make 15 but in ALL gears it will drop to 0. The power is not there either. I dont feel like its even stock power right now. Can anyone help explain what it may be? I have searched for weeks and with no avail... I have replaced sensors and such due to searching but they have not helped with my issue. I have tried doing the tank delete and bypassing the solenoid but did not work.. But have not messed with the Wastegate due to the fact i dont want to mess it up..

Lastly,

NO CODES. Thank you for reading.. I do have torque app and have no stored codes, pending codes, or anything.. Nothing

 

bump

 

bump nothing?

 

Need to see a data log from this car to tell you more because it sounds like you checked for boost leaks and a few other issues. Any Pending DTCs if you scan the car? The wg preload should have been setup correctly when the turbo came to you so that should not be an issues but check to make sure the arm is in the middle of the rod (there are 2 holes driled in the rod and the arm should be in between those holes).

 

Thank you for replying! I actually have my tune throught wot-tuning.com. But I can upload the tune for you.. The tune is my wot pulls that they are currently looking at. I can also share a pic I took of the wastegate. I just have to figure out how haha.

 

 

Can I send the file to you? Its a datalog from ezflash in the .tdlx format.. I dont know if I can post that on here?

 

only people that can read a .tdlx is trifecta.

Definitely is either a boost leak or something's messed up in the tuning. Best thing to try again the soapy water trick. Get a spray bottle with water and dish soap, don't shake it to get bubbly, turn the car on and let it idle. Spray everything and I mean everything. Map sensors, intake manifold, charge pipes, vac lines, etc... Just about anything can cause **** issues. Even if it's something small.

 

I figured it had to be something before the motor/turbo install since I had boost issues before that... I just cannot pinpoint it.. Ive tightened everything I could tighten.. Ive changed all vacuum tubing. Ive changed map(both) maf, and boost solenoid sensor.. tried bypassing the vacuum tank but no luck. I completely lost.. I do have a tad rough idle at cold start after the cat warmup but as soon as the engine gets warm it goes away and I sit at -19 to -20 for vacuum.. I get 15 psi in 4th but it drops to 0 pretty quick and under the trifecta tune I get nothing close to 23 psi and still drops fast.

 

Also AFR is crazy. I am sitting around 14.8 under wot and it jumps all around during cruising.. never ever seen 12.8 or anything close during wot. Also have no codes and no pending codes or any history of codes.. Only time I will see a code is if I unplug a sensor but as soon as I plug it back the code is cleared.

 

Anyone else??

 

Possible Evap issue as far as the A/F but never seen an Evap issue cause lack of boost. I keep thinking boost leak.

 

If its a boost leak... where? I know its not in my piping, sensors on the piping, and the bpv ive checked all numerous times and the t-bolts are to the point I can barely turn anymore.. I feel I might bend the pipes if tightened anymore.. haha.


Could it be on the turbo? Even though that was pre-built by ZZP and then chevy installed it, but here in Guam chevy doesnt have tech 2 or anything like that.. They literally didnt know what a boost leak was.. Also the metal clip was missing on the wastegate actuator sensor but I put a new one on.. Didnt work, and the sensor itself moves(not tight) could that be it?

 

Could be that U should never goto Chevy again and they didn't install right and u got exhaust leaks. Find a different shop to do ur work if they are so bad at it.