Background:

2009 Cobalt SS/TCProblem:

I just finished installing my upper and lower charge pipes, as well as the intercooler, and decided to take it out for a spin. Took it down the road, less than a mile, moderate boost (~10 psi or less) through 1-3 gears , then shifted to 4th hit ~17 psi and heard a loud pop. Pulled off ASAP, popped the hood, inspected. Nothing leaking, no oil/fuel/coolant spraying, etc. Drove the car back home (car had zero boost in all gears and threw a CEL but ran okay - no indications of mechanical/engine damage). Pulled in the drive way and identified that the coupling from the turbo to the upper charge pipe was very loose (likely source of the loud pop) but did not completely disconnect from the turbo itself or the charge piping, just loose.

Before I tightened up the T-clamps on the coupling, I pulled out the Code Reader I have (Actron CP9680) to see the exact code. It was P0101 (MAF sensor problem). I unhook the code reader properly, let the engine cool, and proceed to tighten up the coupling. After I re-tightened, I started the car up to see if the CEL would clear - it did not. The car started fine, no issues, no problems with the sound of the engine, everything was okay, besides the CEL. So I pulled out the code reader to clear it.

After I cleared the code, I tried turning it over, it started fine (no noticeable engine problems, again, the car ran fine home after the pop, and started fine prior to clearing the code after I tightened the coupling). However, the car shutdown shortly after I turned it over (like losing all power) and the oil pressure light came on. There are NO CELs currently on the car, but the car will not stay running after the initial start up. It succumbs to the oil pressure light and turns off but the car starts fine and normal.

Questions:

1) How tight are the T-clamps on the couplings for the charge piping suppose to be?

2) What code(s) are you suppose to get if the charge piping comes loose?

3) Has anyone ever experienced clearing a CEL with a code reader only to get other alarms, like the oil pressure trouble light, immediately after clearing the code? I do not have an oil pressure reader so I do not know the exact oil pressure. However, there are no apparent indications of problems with the oil system.

4) What ideas do you guys have as to fixing this "issue"? Any suggestions or past experiences?

I really appreciate any and all insight to this issue!!

Ryan

 

You have another charge pipe off, the loud pop was the charge pipe blowing off the connector. Recheck every connection not just the turbo to hot side.

 

Agreed. As for how tight the clamps should be, tight enough that they don't come off, but don't compress the pipe.

Also, hairspray, use hairspray on the ends of the charge pipe to get them to hold to the intercooler better. Spray the inside of the couplings and spray the outside of the intercooler inlets.

P0101 is a boost leak about 90% of the time. We have seen it a thousand times.

Check all of your connections. Could be the hot, cold side or at the turbo.

 

Thanks for the replies! Couple things were wrong: the MAF sensor was partially disconnected, and the outlet of the intercooler coupling to the lower charge pipe inlet partially came loose. I made the corrections and took it out for a spin. All seemed well but I have a couple of questions:

I didnt really step on it, but when I did, the boost seemed to cut off early and not go as high. Does this seem normal? I have GMS1 installed with an intake, exhaust, downpipe, upper/lower charge pipes, and intercooler. I reached 17 psi in 4th, ~14 psi in 3rd, ~12 psi in second, nothing in 1st. I felt like I had higher boost with the OEM intercooler and charge piping. Does anyone have any thoughts??

Thanks!

 

GMS1 should be 21-25 psi and be in that range for 3rd and 4th gear.

Keep checking for leaks because it seems like you still have one.

 

Same thing happened to me when my lower CP blew off the intercooler. Oil pressure light came on, my wideband went to 9:1 and the car died.

 

I had the same symptoms (oil pressure and would not stay running) when my lower CP blew off the throttle body a week or so ago, Im also on a hahn lower CP and stock IC, with similar issues with lower boost but I attributed that to MAP sensor issues ive been having, I will have to do a full boost leak test and see, it sounds like a logical issue however.