My 2006 STi is back firing when I rev my engine around 5k-7k The exhaust and DP are still all stock. BOth cats are still on but I can hear mycar backfire from the muffler. HOW BAD IS IT TELL ME MAN!!
How loud is it? What about a warranty, are you stilll covered? If so, just go to the dealer. 5-7 under heavy load? I thought backfires were more common in the sti, could be wrong... Otherwise, do you have a stock bov? Could check for leaks. running rich? Maybe check for any leaks at the gaskets throughout your exhaust.
My vote's for overly rich. My NA car does it, too, when you get off the throttle in a hurry and a few unburned hydrocarbons cosy up to that toasty warm exhaust manifold. It makes them very excited. Stuart.
Ok, backfire or afterfire?? Backfire is going to go through the intake, and afterfire is going to go through the exhaust. A afterfire happens when you cut the throttle and it goes lean. The is just enough in the system to produce a explosion in the turbo when it hits the hot turbine wheel. That will be normal when you free rev your motor to 7k. Now if you are backfireing through the intake, you will have some problems. Russ
man dude if you think you have a noise problem or issue just hit me a Pm. I'm from the same area I could swing by on my day off or something and take a look at it.
Most people don't know the difference. Don't know why that is. One of those words that gets misused so much it just takes on the popular meaning, I suppose. Stuart.
That is why I explained it. Everyone also thinks it happens because of a over rich problem. Another false statement that gets thrown around like it is a law. Russ
if it was actually backfiring into the intake manifold you would see boost on your boost gauge. I have had this happen before. not very fun. also the popping/cracking noise will come from the engine bay not the muffler.
If you have an atmospheric BOV, your engine does run rich everytime you free rev or shift. I have the wideband logs to back it up.
But it is the lean condition that creates the poping, cuz I have a recerc bov and my car does it. I also have wbo2 logs to back it up.
