Ok, weird issue, 2002 camaro SS, stock. Car was running perfect, car sat for a couple weeks, finally take it out today. Starts up fine, drives fine until I get on it, hit 4500-5000RPM range and the car just doesn't want to go, almost likes its choked. And at the same time, I hear a rattling noise coming from the drive side, engine bay area, and the Service engine light starts blinking. I get off it, drive fine at the lower rpm range, doesnt make the rattling noise and the service engine eventually stops blinking and goes away.
Oil pressue is fine, car is not over heating.
I bought some octane booster, filled it up with super, drove it around for a little bit, same thing happening.

Anyone ever experience, have any ideas?

Thanks

 

Pull your valve covers. You have either a bent pushrod or a broken valve spring. Do not drive it any more than you have to or you might be buying an engine. Take the covers off and do a thorough inspection.

 

Sounds like detonation and a lean condition going from your description. Do you have any diagnostic equipment available to you? The flashing SES is an engine misfire and may help to quickly identify what cylinder is faulty.

 

P0171 -Running lean is the code I got.

 

tow it to a shop and look at the valve springs/pushrods.

 

You can try changing your fuel filter to see if that helps. There's a chance your fuel pump or pressure regulator is on the way out, but you need to check fuel pressure to verify.

 

+1 on fueling issue. As noted above, replace fuel filter, check fuel pressure. Also, look into having injectors cleaned. It's likely engine knock due to a lean condition; again as already noted. Once the knock sensors indicate engine knock, the PCM will reduce timing in order to reduce the chance of engine damage. The lean condition & reduced timing will cause the engine to bog.

Agree, as well, regarding having a look under the valve covers, just to be sure that there hasn't been any spring/pushrod damage resulting from the knock.