Car will not idle/boost and stumbles under acceleration
10-21-2007, 12:38 PM
#1
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Car will not idle/boost and stumbles under acceleration
Last night I was driving home and everything was fine boosting good.
One thing I noticed was after the venturi delete I could not hit higher than 15 psi on the boost guage, no matter how high I turned my dial o'doom.
Before I did the venturi delete I could hit 20 psi easily.
I think the check valved hose might be the cause of that.
Anyway, as I pull away from a light I'm pretty sure I was under boost all of a sudden the car falls flat on its face so I step off the throttle and the next thing I see [!] warning light and no oil pressure so I think:
1. OH **** blew a rod bearing
2. OH **** timing belt went kaboom
I pull over with the engine turned off, pop the hood, dont see anything funny or smell anything funny, no fluids pouring out from underneath...
so I get back in cross my fingers and try to restart the car.....it fires right up goes to idle, starts stumbling and dies.
I figure I didn't hear anything funny engine fired just fine so I try it again and this time as soon as it fires I rev the engine, and it revs up fine.
Anyway, the rest of the drive home was a crash course in Heel/Toe driving, but I made it home.
HERE ARE THE SYMPTOMS:
-car fires right up, will go to idle and starts stumbling after 2 seconds then it will die.
-I can keep the engine running with the throttle.
-The car accelerates fine in 1st/2nd but in 3rd/4th/5th if I push the throttle too much it will hit a wall at 2500 rpm and start stumbling really bad.
If I ease on the throttle it will accelerate fine.
-THE CAR WILL NOT MAKE ANY BOOST. I can make maybe 5psi in first then it hits a wall and stumbles like crazy and wants to die.
I'm thinking its a huge vacuum leak somewhere, but all my hoses look fine.
I can't see much of the J-boot though, so maybe there is a hole there somewhere....
One thing I noticed was after the venturi delete I could not hit higher than 15 psi on the boost guage, no matter how high I turned my dial o'doom.
Before I did the venturi delete I could hit 20 psi easily.
I think the check valved hose might be the cause of that.
Anyway, as I pull away from a light I'm pretty sure I was under boost all of a sudden the car falls flat on its face so I step off the throttle and the next thing I see [!] warning light and no oil pressure so I think:
1. OH **** blew a rod bearing
2. OH **** timing belt went kaboom
I pull over with the engine turned off, pop the hood, dont see anything funny or smell anything funny, no fluids pouring out from underneath...
so I get back in cross my fingers and try to restart the car.....it fires right up goes to idle, starts stumbling and dies.
I figure I didn't hear anything funny engine fired just fine so I try it again and this time as soon as it fires I rev the engine, and it revs up fine.
Anyway, the rest of the drive home was a crash course in Heel/Toe driving, but I made it home.
HERE ARE THE SYMPTOMS:
-car fires right up, will go to idle and starts stumbling after 2 seconds then it will die.
-I can keep the engine running with the throttle.
-The car accelerates fine in 1st/2nd but in 3rd/4th/5th if I push the throttle too much it will hit a wall at 2500 rpm and start stumbling really bad.
If I ease on the throttle it will accelerate fine.
-THE CAR WILL NOT MAKE ANY BOOST. I can make maybe 5psi in first then it hits a wall and stumbles like crazy and wants to die.
I'm thinking its a huge vacuum leak somewhere, but all my hoses look fine.
I can't see much of the J-boot though, so maybe there is a hole there somewhere....
10-21-2007, 02:28 PM
#2
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You popped off a charge pipe. happened to me the other day. check the pipe from the turbo to the intercooler, and from the intercooler to the throttle body. this is a MASSIVE boost leak.
Mine happened when I was trying to impress a girl.. throttling up to show off boost, shifted, and heard a "POP! PSSSSSSSSSSSSSSHHHHHHHHH" sounded like a guy with an obnoxious blow off valve in his WRX. Girl was impressed... until I told her it was a bad thing and stumbled the car home to take her MINI to the destination...
but EXACT same symptoms. won't idle, stumbling, won't go above 2,500 RPM... go through, check all the charge pipes, etc. do you have a factory airbox? Mine was the connection between the intercooler and throttle body, on that "T" connection opposite the bypass valve. not immediately obvious because the airbox snorkel was in the way.
Mine happened when I was trying to impress a girl.. throttling up to show off boost, shifted, and heard a "POP! PSSSSSSSSSSSSSSHHHHHHHHH" sounded like a guy with an obnoxious blow off valve in his WRX. Girl was impressed... until I told her it was a bad thing and stumbled the car home to take her MINI to the destination...
but EXACT same symptoms. won't idle, stumbling, won't go above 2,500 RPM... go through, check all the charge pipes, etc. do you have a factory airbox? Mine was the connection between the intercooler and throttle body, on that "T" connection opposite the bypass valve. not immediately obvious because the airbox snorkel was in the way.
