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The MSM is now regularly backfiring on the 1-2 upshift under full throttle. Happens every 40th time or so, a small pop from the exhaust. Couldn't figure out what the noise was at first -- it isn't very loud -- but I have now determined that it's either a backfire or else someone is hiding in my trunk and shooting a gun.
Any cause for concern here? :confused:
S.
Is it running rich? Any sign of black/soot around the tail pipe?
is it a factory exhaust? i friend of mines car will pop like that between shifts as well.
Not much. Certainly not more than I've had in any other car. Certainly, some gases aren't fully combusting in the engine, but I don't know whether this is cause for concern. I do want to answer this question before I install the FM downpipe. ::MrT::Quote:
Originally Posted by sammm
Yes, it's the factory exhaust.
S.
How many miles? Have you checked the gap on the plugs? Is the air filter clean?
RJ
5,000 miles. Can't imagine it's the plugs. I did drop a K&N filter in a while back. Hmm....:scratch:
S.
My 87 camaro used to backfire like crazy, but the timing was off.
Quote:
Originally Posted by srivendel
Lemme guess... you're shifting right about 5k?
Mine does that too... the a/f goes WAY rich right there as teh boost kicks in. If you let off and shift before winding it out a ways you can get a backfire. Mie got worse with the FM DP.
Its' pretty easy to replicate if I want to.. also easy enough to avoid...
My '02 does the same thing... 3/4 throttle or more, shift between 4500 & 5500, POP!Quote:
Originally Posted by rx7gslse
Ding ding ding! We have a winner.::EvilBanaQuote:
Originally Posted by rx7gslse
Glad to know I'm not alone. Interesting that it got worse with the DP. I admit: it does make me feel pretty ricey (in a bad way).::Oscar::
S.
Quote:
Originally Posted by srivendel
I dunno if it really got worse, or if it just got louder with the elimination of a silencer... Eitherway, I noticed it more :)
But yeah.. I've got the wideband gauge in teh car, and you can just see it pegg teh needle at about 4.5-5k rpm for anything under positive boost pressure. Drops right down below 11:1
would na's have a small series of backfires? i have a borla and TP. and i get it sometimes. doesnt bother me though. just wondering if that was it. ;)
My car used to backfire every once in a while in between full throttle shifts.. That was before I went FI and I had no cat so.. im guessing thats why :rolleyes:
if you have a turbo car with a bov vented to atmosphere it will backfire, and if you shift at the rev limiter with no muffler it will shoot out a flame
My FM turbo pops a lot. I LIKE IT!:drive: