When mashing the gas in 1st gear, I get several loud backfires in high rpms, right before shifting into second. This only happens when starting out slow in first gear. On the highway this never happens. I have new plugs, wires, 02s, and no cat. Does anybody know what this could be? I'm hoping maybe a dirty MAF or bad coil. Opti maybe? Thanks for any advice.

 

Nobody has any suggestions?

 

Maybe a leaky intake gasket getting you lean at high rpm.

 

does it happen right after you let off to shift?

 

rev limiter?

 

There's no rev limiter on the car. This has progressively been getting worse. The car runs fine until high rpms, when the transmission wants to shift. My plugs and wires seem fine. Can this be my opti going bad?

 

I'd replace the coil first (a lot easier and cheaper than an Opti). Typically you'll see increasing ignition issues as RPM goes up, to the point where the engine might not rev past something like 5K and will be popping and backfiring like crazy. As the engine heats up, the RPM where this happens gets lower, until it dies.

Dave

 

I had a couple of backfires at high RPM under max load, and a slow cold start as well. Turned out to be low fuel pressure. New fuel pump solved it.

 

I( have had this too. It could be a couple of things.
1. fuel pump. test pressure at schroeder valve. usually a mechanic will check it free or small $$.
2. opti.
3. plugs/wires bad fouled.
4. fuel filter.
5. intake air leak.
I would check these out. these are the most likely sources I can think of from my experiences with owning 4 different LT1 f-bodies.
Good Luck!!

 

i had same problem, then i replaced my valve springs and problem went away. good luck.

 

I changed the coil and the problem was solved. I bought one from Autozone for $15.99 and it came with all of the screws and everything. Installation was pretty simple, I didn't have to remove the cold air intake or anything. My intake elbow tore though. Does anybody have one for sale?

 

intake elbow tore? you mean a stock elbow? I may have a stock one laying around. I'll look. How did it "tear?"