Ok i have a z28 with 89,000 miles all stock no mods and is my DD. The other day before going to work i start the car early to get some game and upon starting the car makes a loud popping nose and start making this loud knocking nose. The only light that is now on is the service engine soon and there is no oil leaking or any other problems. here is a video of start up and running for a few seconds. Any help would be great and thanks you guys very much!!



Video of start up

[autostream]http://autostream.com/camaroz28/?page_type=firebirdplayerthumbnail&framepage=2635& transactionid=1337453198-7017676224&posted_by=Z28Goat_www.camaroz28.com&you tube_video_id=SgkgPz29iW8[/autostream]

 

Is the engine running rough? If it is not running rough, I would say it sounds like an exhaust leak. If it is running rough,I would pull the valve covers; you may have a broken rocker stud or a collapsed lifter.

 

Have you scanned it for codes?

You're going to have to provide more info, like the year of the car. Not all years of the LT1's are the same.

 

Hard to say where the noise is coming from. Can you pinpoint exactly where it might be? It does sound like something like an exhause leak, but hard to tell. Does your oil pressure look normal? You can buy a stethoscope and listen to the valve covers and other things to help locate the noise without removing anything. Sounds real bad and I would not even run it, except to diagnoise. Had a broken crank years ago and sounded very close to yours.