need4z

iTrader: (5)

Hey guys. I got my Z06 going last week after 1 year of everything. lol.. I fixed 3 noises soo far. I get a flashing check engine light now and then. Sometimes it goes sway after 5 seconds and sometimes it stays for a minute. By the time I get my scanner o it it reads no issues. I think it could be O2's since I used a lot of wd40 to reconnect the exhaust. Anyway getting to my question. I did a baseline mail order tune just to get it up and running by a very reputable east coast company. haha. Cant afford a complete dyno tune yet. They say they get the tune as close as they can without having the car there and having a wide band etc.. Could this pop bang noise be related to the tune? Can you get a backfire from the throttle body area because I know thats where it s coming from. It happens either simultaneously when the engine catches or a second after the engine fires. Otherwise the car is running amazing for just a mail order tune and all my mods. Could a MAP or Mass airflow sensor out of tune or my ported LS2 TB for that matter cause this? It only happens on startup only. Its not super loud but you can definitely hear it. Didn't hear it when the Z06 was ice cold but every time its started after being warmed up its there. Hoping its fixed in a tune. Suggestions fellow LS gearheads? Mods in sig. May I add its almost slightly metallic almost like a backfire from a carb sorta.

Thanks soo much

Derek

Edit:: I have checked all my valves and they are fine.

need4z

iTrader: (5)

thanks LS1tech. I get the first noise like that in the history of LS1 engines which no on one has any idea about. Oh well time for a real mechanic now.

01 Bad Mutha F*****

I had a 2000 Buick LeSabre that was doing the same thing. I let the car sit for a week and when I next started it the intake manifold exploded and there were four foot flames when I opened the hood. The car was a write off.

My advice - check for a fuel line leak or bring it to a mechanic

need4z

iTrader: (5)

AC compressor rattle.. low refrigerant... removed ac belt and the sound is gone. Remarkable how things work sometimes! LOL