So I recently got a cobalt ss/sc g85 with stage two. I noticed that it wasn't pulling like a stage two should. I took it into the shop they replaced the thermostat, MAF, and an o2 sensor cured the engine light problem but car still didn't pull like it should. I would get the correct 15lbs of boost but no pull. My buddy had said that it might have a clogged cat so we pulled an o2 sensor out to make an exhaust leak to see if the power had increased and still nothing. Any ideas on what this could be? It seems to me like it's an airflow issue somewhere whether it is actually still a clogged cat or if its something else like my intercooler. Help please. Everything on the car is stock besides GM stage2.

 

Make sure your intercooler pump is working. If your cat was clogged you'd be over boosting a few psi. And gm's canned tune isn't going to be that great anyway get a custom hpt tune.

 

Is there anyone around you with HP tuners? They can data log your car there Make sure the tune is ok and then look at other problems like heat exchanger messed up, or intercooler pump not working.

 

what he said

 

The dealer checked my tune to make sure that it was good and they even reprogrammed to pcu so that isnt the issue i dont believe. Also to the over boosting i have hit 18 psi.

 

If you're overboosting your cat is most likely clogged.

 

this^^^ and check you ic pump

 

alright ill check it out if that doesnt work ill post again thanks everyone for the help!!

 

If ur cat is clugged dont order another stock one waste of money get a zzp downpipe or just cut out that obe for a temp fix, catless will sound like **** tho.

 

yeah i would check you ic pump and take a look to see if the cat is clogged.

 

yeah i plan to order a full zzp exhaust, long tube headers, 3 in DP and 3 in exhaust. thanks for all the help. Does anyone know about any good shops to get a tune in Milwaukee area? I found shops that tune obviously but i can't find any that have good tunes for the LSJ.