sr cutting out at boost! leak tested. what next?

[sicknamehere]

so my s14 sr20det is cutting out at boost. i had a REAL boost leak test done and there are no leaks. it's cutting out at about 5psi. i originally thought my bov was dead because i was starting to get compressor surge and the bov wasn't opening. so i got an hks because they're awesome and switched them out. i realized my T fitting was broken causing a small vacuum leak so i hooked my bov directly to the intake manifold and eliminated the T fitting. bov works, no more compressor surge, but still cutting out in boost. any advice?

[Mr.Y]

Had a similar problem on my s14 sr. Check coil packs, plugs, check what your vacuum is, mine read around -21 which is where it needs to be. Could be a dying fuel pump. I tinkered with my car for almost a month checking and rechecking, buying a pump and tps...ended up being bad wiring at the IAC valve, so i cut and resoldered the wires, Bamm, ran like a champ.

Hope you get it fixed, i know first hand the shitty feeling Good luck bro

[sicknamehere]

Originally Posted by Mr.Y

Had a similar problem on my s14 sr. Check coil packs, plugs, check what your vacuum is, mine read around -21 which is where it needs to be. Could be a dying fuel pump. I tinkered with my car for almost a month checking and rechecking, buying a pump and tps...ended up being bad wiring at the IAC valve, so i cut and resoldered the wires, Bamm, ran like a champ.

Hope you get it fixed, i know first hand the shitty feeling Good luck bro

wow, that was a lot more info than expected. thanks man. i'll start checking things

[Tantwoforty]

So i would check:
spark plugs
fuel pressure
timing
check again for a boost leak, where was the tester put in place?
how close to the turbo is the maf?
do you have a wideband? get one
could be the cas
could be the maf and or wireing
also, is it throttle related or boost related? like if you mash it before boost what happens?

[sicknamehere]

Originally Posted by Tantwoforty

So i would check:
spark plugs
fuel pressure
timing
check again for a boost leak, where was the tester put in place?
how close to the turbo is the maf?
do you have a wideband? get one
could be the cas
could be the maf and or wireing
also, is it throttle related or boost related? like if you mash it before boost what happens?

spark plugs are about due to be replaced.
boost leak tester was put in place through the hose that connects to the brake master (sorry, i'm a n00b)
maf is about 1.5 feet from the turbo
i have an aem digital wideband
it's boost related from what i can tell. it only cuts out in boost. i only go into boost when flooring it though. doesn't cut out in 1st below 7k (i don't push it to redline) cuts out in 2nd around 6k-6500, cuts out in 3rd around 4700. boost kicks in around 4500 rpms.

[wanabedrftr]

im having a similar problem too lol

done everything everyone has said still haven't solved it.. SO ANNOYING

do you have stock intake rubber tube? ive heard of those closing under boost causing lose of power.. im changing mine out tomorrow to see if it solves my problem

[sicknamehere]

Originally Posted by wanabedrftr

im having a similar problem too lol

done everything everyone has said still haven't solved it.. SO ANNOYING

do you have stock intake rubber tube? ive heard of those closing under boost causing lose of power.. im changing mine out tomorrow to see if it solves my problem

i don't think so. let me know though

[sicknamehere]

so, i'm going to try to keep this thread alive until i find the problem. i just read that a loose engine ground can cause the same problem. or just wiring in general. so, tomorrow while i'm fixing all the stupid shit in my altima, i'll try to at least cross a few things off the checklist.

[jonsparrow]

iv been having the same problem for months. it got so bad that i stopped driving the car. im currently waiting for splitfire ignition system to show up to see if that fixes it.

[fullthrottle]

Make sure your spark plugs are gapped correctly and your mag is clean. If you are running a stock intake, its probably collapsing under high suction.

Sent from my Desire HD using Tapatalk

[Tantwoforty]

I dont think thats a good way to do a boost leak.
Becuase that hose goes to the intake manifold, from there the pressure is going to escape through the throttle body, through the pipes, through the intercooler and to the turbo, but then its going to just escape out the turbo intake..
When i do boost leak checks i have a home made tester, it fits on intercooler piping and it uses a pressure gauge and small valve, i put it in place of the turbo outlet.. (the pipe that goes to the intercooler) and then i pressurize that, the pressure this way will go through the pipes, through the IC through the TB and into the cylinders (if intake valves are open, if not it will stop here.) and then since the pressure cant get out the valves (one set or another) you will begin to build pressure, i pressurize it to 5psi and see if it holds it or slowly decreases indicating a boost leak..
but i could be wrong..
my money is on boost leak from your BOV
what are your ARF's doing when it cuts out?

[fliprayzin240sx]

Well, when it cuts out, what the hell does your wide band say? Is it lean or rich? What fuel pump do you have? When it hesitates, does it puff black smoke like its dumping lots of fuel? Also, did you double check your CAS timing?!?!

[Sliderintrainin]

i know this is old but did you ever figure out your problem? if so what was it. having similar issues.thanks
when i get into boost afrs drop to like 9.9