Hey guys a few days ago I had my car in for a supercharger rebuild and a new after market boost/vacuum gauge install from Glow Shift. My tech had my sc off of course & apart while he replaced my snout bearings, snout seal, & greased up my case needle bearings with the needle bearing grease all bought from zzp. It took a few hours but we completed the rebuild & put my sc back on. We also like I mentioned replaced my factory boost gauge which hasn't worked in years with a boost vacuum gauge from glow shift. We installed the boost gauge the correct way however it would flash & not work after closer inspection we found that glow shift had sent us a new gauge with faulty wiring as the wiring that went into the back of the gauge had a poor connection. The only way to make it work was for my tech to hold it in with his finger and the 2nd he let off it would go back to flashing again. Anyhow that's another story. So after the rebuild & gauge install we fired up my bolt & noticed that the idling kept bouncing around. My tech took it for a spin & the 2nd he got it out on the rd & attempted to shift into 2nd gear he threw the check engine light went into reduced engine power mode & threw about 5 other codes. We thought maybe it was the computer not liking where we spliced into the boost vacuum line for the boost gauge so we unhooked the boost gauge vacuum line since after all the dam gauge is faulty & I have to deal with glow shift on a new one & we reset & cleared the codes. After that we took it back out for a rd test and everything seemed fine. Well 2 days later I went to start it & my check engine light was back on again & the 2nd I went to go into 2nd gear I got the dreaded reduced engine power again. At this point I knew it couldn't be the boost gauge since we had unhooked the vacuum line. My car mind you has ran beauifully for years I haven't had this issue since installing my stage 2 kit. Anyhow I took it back to my tech after work today had him clean out my throttle body real good with throttle body cleaner & clear the codes. We took it out for a spin & everything seemed ok. We pulled off to the side of the rd & kept it idling while we looked at the poor connection on the back of that boost gauge. What was strange is my car was running fine however when my tech started to play with the faulty wires on the back of that boost gauge I started to get that idling problem again followed by the check engine light & reduced engine power. He checked his scanner & we had the same codes again. He cleared the codes & basically sent me on my way puzzled. In the mean time he is having me work with glow shift to get a new gauge so that he can replace that he also recommended that I pick up one of those pre cut silicone vacuum line kits for my bolt since some of my lines are becoming old & fraid. I'm turning to you all hoping that someone out there can shed some more light on this for me. So far after resetting the codes for the 3rd time & the TB clean out today my check engine light or REP has not come back however the only thing I did was drive home & I babied it in order to prevent that from happening. Below you will find the codes that have continued to pop up. My question is what could have or is still causing this ? Again my car hadn't had these issues in over 2yrs & she was running great until my sc rebuild & boost gauge install on Friday. Is it possible that dabree or needle bearing grease could have found its way into the throttle body ? If so then why did the TB clean not do the trick ? Or could this dam glow shift boost gauge with the faulty wiring be causing these issues ? Sorry for the long post guys I just wanted to be as detailed as possible & like the rest of you I have dumped close to 8 grand into my car in mods & labor & I can't have it all waisted on this.

Here are the codes that have been thrown each time.

P0069-SC inlet pressure SCIP-Barometric BARO pressure correlation

P0121-Throttle positions sensor malfunction

P1101-Intake airflow system performance

P0068-Throttle body airflow performance

I have a Injen CAI & a stock still original LSJ throttle body. I also have the GM stage 1 & ZZP stage 2 kit. My bolt is a 2005 Chevy Cobalt SS/SC LSJ 2.0L. She has about 173k miles on her. Most sensors including my MAF sensor were all replaced about 2yrs ago.

 

holy block of text.....

first of all, how can you have GM stage 1 and zzp stage 2? they consist of the same components. what pulley size is on the car and what tune are you using?

 

MY EYES.....

Did ANYONE flap the throttle body at all?

 

Sorry for the confusion on my stage kits what I meant was is I went to my GM dealer & had the GM stage one kit done which as you guys know was just the high flow fuel injectors and the re flash or tune of my computer & then I purchased the pulley & hub package from ZZP along with their stage 2 belt & had my tech install that which officially took me up to a stage 2. My pulley size is 3.0.

as far as flapping the throttle body if I'm understanding your question then yes yesterday when my tech cleaned out my TB with TB cleaner he did reach in & flap open and close the TB in order to make sure it was free & wasn't sticking & he said it was fine.

 

I had the same issue last year on my '05 SS. My setup is all OEM. I replaced the SCIP sensor, cleaned the baro sensor that's mounted on the engine, checked/cleaned the wiring, cleaned the MAF sensor and made sure there weren't any air leaks. I cleared the codes and it's been good ever since.

 

Most likely you have an intake leak