ok i had a previous thread on here talking about my CEL rondomly comeing on https://www.cobaltss.net/forums/2-0l-lnf-performance-tech-153/cel-207612/. just got car back drove about 40miles total CEL back on can the K@N drop in be affecting the car to the point it runs that lean? car runs and drives fine this time

the code was P2187 they did an induction clean as well as a TSB for cleaning fuel injectors, after this was performed i was notified that the car was missfireing on 2 and 3 they re cleaned the injectors and gave it back to me.

UPDATE
just got car back from the new dealer took them less than a day to find a vacume leak, wow im for sure not going back to randy wise.

thanks all, im so glad it wasnt the K@N ive never had issuse with them

 

Thats kinda weird, I mean the drop in obviously takes in more air but not enough to throw a CEL

 

wow.. never had happend to me yet with 3200 miles so far.

 

I forgot to reset my ECU after dropping the K&N drop-in in and the car hated it at first. If you haven't tried disconnecting and reconnecting the battery/ECU to reset the ECU and therefore the fuel trims, try doing that. It may be having a hard time adjusting.

 

Vac leaks cause the lean code. Check your PCV snout on the air intake to make sure you didn't crack it when installing the filter.

 

well thats very strange, I threw in the K&N and didnt reset my ECM and the car worked perfectly fine, lol.

 

if you have a way to look at fuel trims(dash hawk ext) see what your long terms are and that could tell you if its causing a problem ltft with the drop in are around 3 usualy and with the aem they go as high as 15
Josh

 

My fuel trims were 5% off with just Drop In filter.

With GM stage 1 it's almost 0% so you probably have something else going on that is causing this.

 

Exhaust leak?? BBG was throwing similar codes when he had his cutout open.

GMS1 does NOTHING with tuning for an intake or air filter....

 

Well I am telling you what I have seen. Maybe it was that i never reset my computer before GM stage 1.

 

Or maybe it was right after your flash and the car hadn't started trimming yet lol. I have a stock 09 and GMS1 09 file, exact same intake calibration.

 

Nah I have reset it a few times. It hovers from 0-1%

 

Well that's good for you! Can you monitor the STFT's too? How much swing do they have?

 

I was having misfire problems as well. They did the same tsb to clean the injectors but to no avail. They finally replaced the injector and I've had no problems since. except one of the coil packs died and had to be replaced. Did GM just use cheap components or something?? Makes me wonder what's next to fail. I hope I'm wrong.

 

well the code on it was the same as last time, this was with the stock air filter in it last night i take it out everytime i take the car in since they know me from my last car being modded.

decided not to take it back to that dealer they have a horrible REP and they never fix any of my car right the first time my parents wont go back there eather. its at a dealer in monroe, mi they seem to know alot about the SS cobalts so im happy i took it to them randy wise in milan had no clue of the rear brakes nor had the parts plus this hurts me to say this since im young there was no tech working the dealer that looked over 28.

hoping this dealer can fix it, thanks for the advice guys, my dads thinking someone put something in the tank while it was at friend appartment bad neighborhood

 

It's possible the oil from the K&N got on the MAF. A lot of people experience these issues after cleaning and over-oiling the filter. Try cleaning the MAF, as you received the same problem with the stock filter in place.

The dealer likes to jump to replacing the injectors on the TC's ive noticed, its not normally the issue.

 

System too lean at idle is almost always a small vacuum leak in the system. Clean the MAF and check all the vacuum lines, CPs, IC end tanks, etc. Seen that code happen because of a missing oil filler cap as well.

Stage 1 uses the exact same MAF tables as your stock tune because both are based on the stock airbox, filter, and snorkel so the fuel trims should be the exact same. If they are truely not the same as before there is no logical explination for that.

 

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