I recently had a nitrous backfire that blew a hole in my intake manifold. I swapped the LS6 intake with the stock LS1 intake and the engine runs fine. Recently I have noticed that the engine will backfire at WOT tip in and sometimes at low rpm's. I have HPTuners and a wideband and I was just wondering how I would go about getting started on finding this problem and fixing it with the software; and how I would determine if it is a fueling issue vs. a timing issue.

Thanks everyone

 

I might be way off here,but did you check your plugs after the nitrous backfire?
You could of smoked 1or2 and that is your back fire (missfire) now.

 

I checked a few of the plugs, and the ones I checked looked fine. That's probably a good idea though to check to rest of them. The only reason why I DO think that the plugs are fine is because the backfire and misfires are intermittent, if I had a smoked plug/s I imagine the frequency of the backfires and misfires would be greater. Thanks for the advice though, maybe I should check the rest of them.

 

did you replace the MAF?

 

You should check all of your plugs and do a compression test on the cylinders. Also look inside the intake for an excessive amount of oil.

I had a big nitrous backfire that blew the back of the intake out... it ended up toasting one of the pistons (broke a ringland) albeit the car still ran good. It eventually started having really bad blowby.

 

What cylinder did you have a problem with the ringland? I heard on LS1's the very last cylinder on the drivers side will always go first during leaning, or nitrous backfires and such.

 

#6 was my downed soldier.

I've seen a bunch of motors break from nitrous... never any real consistant #7 damage. I've seen #6 more than i've seen #7. I've also seen #8 quite a bit.

On a big backfire... it's usually going to takeout whatever piston has the intake valve open and exhaust valve closed at that time.