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Car bogs below 3500 rpm/ boost leak test help

Bear with me here. So, I'm moving my car to my new home. It's about five hours away. First long drive in a long time (car had lots of problems being fixed over the past two years). Half way thru the drive it starts to hesitate intermittently at anything over 1/4 throttle and below 3500 to 4000 rpm. Boost will build and hold but no real acceleration or power. When she hits 4000 or so it feels like a new cam comes in, similar in feel to a VTEC engine. Pulls right away, sounds great, runs the way she's supposed to. I'm pondering the possible problems. First I'm thinking fuel, then maybe spark, and eventually convince myself it's a vacuum problem. Believe it or not I've owned #1316 since '04 and have never done a boost leak test. I unhook the air intake from the turbo, put on the tester. Two pumps of a bike pump and air rushes out of the filter. What am I doing wrong concerning the boost test? Do you think I'm on the right path to diagnose this hesitation problem? Should I refrain from driving the car another four hours this weekend? (I can drive around the problem by backing off when she hesitates and then easing into the throttle a little deeper) Thanks a lot y'all. I now live in the greater Syracuse area, if anybody is close by and willing to give me a hand it would be much appreciated.
 

1990ggsxnj

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Joined
Nov 21, 2008
Messages
525
Location
Blackwood, NJ
Hmm, sounds like it may be going throught the BOV back into the intake tract. What setup are you using? Information on the car would help, such as maf setup, vented vs recirc bov, etc.
 

mikus

Well-known member
Joined
Jan 11, 2007
Messages
2,763
Location
Aurora IL
ehh the "air rushes through filter" part is a flag, there shouldn't be any filter involved.
Are you pressure testing @ the turbo inlet (ie, pressurize the turbo through IC through intake manifold)?
 

1990ggsxnj

Well-known member
Joined
Nov 21, 2008
Messages
525
Location
Blackwood, NJ
If his BOV is leaking it can be going back into the intake inlet piping which the filter is attached to. But as stated, yes it's the "turbo inlet" where you can see the compressor blades which gets the tester attached.
 
Last edited:

I believe the MAF is unaltered. The battery has been relocated and an open element air filter sits in it's place. As for the BOV, I really don't know whether it's recirculating back into the system or going to atmosphere. I bought the car in the state that it's in, which is altered a fair bit from stock. I'll get in there and take a look today. Any suggestions on how to test the BOV? Thanks
 
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