sidewaysil80

I have a 240 hatch with an sr, built head, gt28r@11psi, z32 maf, light weight fly wheel, AFC neo, and a bunch of bolt ons. I just got tuned but the problem is after high rpms or "really getting on it" when I press the clutch (could be when I back of throttle, not sure) the car will just die, howeve immediatley start right back up, sometimes its gets real close to turning off but kick back up... The tuner says its because I'm not using a re circulated bov. I looked into it but I just don't infestand how when I clutch in and coast to stop and it turns off is a result. If anyone has any other ideas of what's causing this or any ideas or things I can try to fix it PLEASE let me know. Thank you in advance

renegade_ewok

When your slowing down and you take the load off the motor, the BOV might not have enough pressure from the vaccuum source to stay closed

What is your BOV?

sidewaysil80

Its a Greddy type rs. It was way worse and I brought it back and he messed with the bov and it got better. I assumed he tightened the spring. (maybe that helps) should I give the bov its own vacum source? Um stumped because ive never used a mafs till now and never had this problem

0wn3r

Loosen nut and turn the adjustment hex bolt more towards "hard". Then recirculate haha, unless your fuel controller adjusts based on the missing air...haven't learned much about fuel controllers yet since I'm basically stock.

Ever notice any stuttering issues when accelerating too?

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97 240sx se

sidewaysil80

Matter of fact first will stutter a lil in higher rpm or usually if its floored, btw I have an adjustable fpr as well (figured that's worth it to mention) also, I appreciate everyones input and help. Hoping to have this issue resolved this weekend

0wn3r

Mine seemed to stutter when flooring it in low rpm's somewhere between 2nd and 3rd gear. The recirculation definitely helped me

If I had access to the photo right now, I'd post it up

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97 240sx se

sidewaysil80

ok i've narrowed it down, the rpms drop ALOT while the car is in gear and the clutch is pressed. when its in neutral and the clutch is pressed it does nothing. also at idle, SOMETIMES, usually after "getting on it" they will drop just as low. sometimes it causes the car to stall, sometimes it shakes and shit like it will and at the last second jump up rpms. at part/half/wide in first and some of second it sputters real bad and the car will buck. it also breaks up at high rpm and is running quite rich. pretty sure the breaking up is a result of fouled plugs from running so damn rich. Any suggestions?

jdm510

i have a s13 with a sr20det and the previous owner said it was normal for it to do what yours does cuz it dont have a recurculation

well after finding lose bad plugs, vacum and boost leaks, then the main problem i found i had was bad injector seaLS

now it runs soo good it drops rpms a lil bit after rev, but never dies no more i can push the clutch and coast to a stop

renegade_ewok

My car has the same BOV and I turned it up, more towards hard and it helped the low range hesitation. I didnt have stuttering/stalling, but it was obviously a factor. I tightened mine all the way until the turbo still fluttered at 4-5psi. THat essentially eliminated the bad bogging I experienced.

Dont worry about compressor surge, tighten away. Some motors in jdm land never came stock with a BOV and surged their way well into the 100k range. Also, its not true surge, true surge sounds really wierd and youll know it when you hear it.

0wn3r

if you ever figure out this problem, fill me in...I think there's several people with the issue. alot of times people, me included, have the a/c on too.

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97 240sx se

sidewaysil80

turns out it was on the wrong setting (2in 6 out as opposed to 5 out) and the dec air feature on the neo wasnt set or programmed. they are retuning with the new settings and programming the dec air feature. but if you look in the neo manual the dec air prevents 99% of what i described.

((sr)) kelly

its because you have your bov open to atmosphere... all the air the maf JUST meterd is released and cannot compensate for the fuel the ecu is dumping into the engine becuase it has already gotten the signal from the maf and is expecting all the air the bov just released to actually be used

renegade_ewok

I have the same BOV on my SR and I vent to atmosphere and never stall out no matter what I do.

It just runs rich. Thats really it.

sidewaysil80

i've run this same set up before the only difference is now i have the afc higher/boost/adjustable fpr. the tune was a bit rich, but the stalling was as result from the dec air function not being set.

lightsource

Yo, I think I'm having the same problem.

Have you found a solution?

YouTube - SR20DET RPM Drop after high rpm's

^^^ is it like that?

lightsource

lightsource

lol_1337

Do the basics. Check for vacuum / boost leaks... wouldn't hurt to check your MAF sensor.
Injectors / Fuel Pump/Filter. Maybe you just have a bad BOV :x. Take it out, replace with a 20 dollar pipe, put in the stock recirculator BOV and try it out.