Boost leak = Backfire => Question
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Boost leak = Backfire => Question Last night I took my uncle for a ride in my car and it just wasn't the same. The only thing I've done differently is I had welded up the cold pipes so I didn't have any more couplers than I needed.
If I eased into the throttle there wasn't a problem, but if I just went WOT then there were several small backfires. So this morning I went out there and looked it over and found that the vacuum cap I had covering the throttle body port was broken. I put a new one on and we went for another ride and we were all good. There wasn't a miss at idle or anything. I'm guessing the vacuum pulled it shut, but once it his boost it threw the air out creating a lean condition and backfiring out the intake.
My question is, what is everyone doing with that port on the throttle body to prevent this BS?
If I eased into the throttle there wasn't a problem, but if I just went WOT then there were several small backfires. So this morning I went out there and looked it over and found that the vacuum cap I had covering the throttle body port was broken. I put a new one on and we went for another ride and we were all good. There wasn't a miss at idle or anything. I'm guessing the vacuum pulled it shut, but once it his boost it threw the air out creating a lean condition and backfiring out the intake.
My question is, what is everyone doing with that port on the throttle body to prevent this BS?
i just have a cap on mine that has held up so far,
a friend though had his welded up and smoothed along with the coolant passages underneath and it cam out nice
a friend though had his welded up and smoothed along with the coolant passages underneath and it cam out nice
Last edited by Tally TransAm; Mar 7, 2010 at 04:34 PM.
I've been through 2 of those caps, mine never came off completely though. Everytime I take a pipe off for whatever reason I always presure up the cold side and spray it with soapy water to check for leaks. Both times the caps were dry rotted and had just started to leak.
Thread Starter
11 Second Club
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From: Summerville, SC
I've been through 2 of those caps, mine never came off completely though. Everytime I take a pipe off for whatever reason I always presure up the cold side and spray it with soapy water to check for leaks. Both times the caps were dry rotted and had just started to leak.
Thread Starter
11 Second Club
iTrader: (43)
Joined: Aug 2006
Posts: 5,364
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From: Summerville, SC
