Big bang in 3rd gear on boost??!!

[zacksgsx]

Yikes, what happened!!?? From a stop I am coming up smartly through the gears. Just as I jump on it and shifting into 3rd gear (3500-4000 rpm) I hear and FEEL a big boom! The engine stops and the trans kicks out of gear. While coasting I push in the clutch and start the engine. No problem, it starts, runs and sounds fine. So I re-engage the trans and drive on. Now I am gun shy about pushing it. Any thoughts on what may have caused this? Thanks, TP
Car-97 GSX, 109,000 miles, stock engine with bolt on's (intake, bov, 3" down pipe and cat back. 5 speed.

 

[95gs200k]

mine used to do the same thing every once in a while. My mechanic told me it was loading up with fuel when it was coming up on boost. We traced it to a bad FPR that would let my fuel pressure spike as high as 95 psiWTF . Might want to look at your fuel pressure.

dj

 

[sawnuoff]

how much boost was you doing, maybe check out bov? have you tried gettin on it in just 1st,2nd?
had an experience similar ended up being stock bov bolts had come lose and one fell out, but my did not quit running or pop outa gear. sounded awful.

 

[Deadly BlaZe]

Yikes, what happened!!?? From a stop I am coming up smartly through the gears. Just as I jump on it and shifting into 3rd gear (3500-4000 rpm) I hear and FEEL a big boom! The engine stops and the trans kicks out of gear. While coasting I push in the clutch and start the engine. No problem, it starts, runs and sounds fine. So I re-engage the trans and drive on. Now I am gun shy about pushing it. Any thoughts on what may have caused this? Thanks, TP
Car-97 GSX, 109,000 miles, stock engine with bolt on's (intake, bov, 3" down pipe and cat back. 5 speed.

I think what you've just experienced is called fuel cut. It's when you're boosting more than what you're fuel system can handle, therefor the ecu cuts off fuel supply to the motor to avoid any major damage. What you felt was probably a very violent jerk right? Also, did this happen while the motor was still cold, or after it warmed up? If you don't already have a boost gauge, get one to see how much you're boosting in 3rd gear. That 3" down pipe and catback can make you're boost spike higher than stock.