Shifting to Neutral causing car to shut off

[DSMnOOb00]

I'm having this idel issue with my car, I just had the engine rebuilt and it runs like a great. It's only when I come to a stop, I let off the throttle, put the car in neutral, when the car's RPMs will drop fast and car dies..
3
when I start the car, its idels good, and when im shifting from gear to gear it shifts okay... its only when going from gear to neutral.

I'm thinking maybe that I dont have enough air restriction? since everything I ported or larger then stock?


my upgrades in my profile are upto date
here are a few of the upgrades in my car

Bolt-on Modifications:
Stock Rebuilt 4G63 7 Bolt
MHI 16g turbo (PORTED)
Injen intake 4" Air filter & MAFT adapter
Dejon Tool Upper & Lower hard piping
Slow Boy Evo3 Exhaust Manifold
Greddy Type-RS BOV
o2 Housing (PORTED)
3' Apexi exhaust system
3' Magna Hi-flow cat (cali legal)
1G 60mm Throttle Body with Port-match intake-Manifold
Walbro 190lp Fuel Pump

 

[keviebaby]

Your IAC (Idle Air Controller) may be out of whack or one of the coils dead on it. This link may be helpful

http://www.dsmtuners.com/forums/newbie-forum/365202-what-does-iac-sensor-do.html?highlight=IAC

This one is how to test the IAC

http://www.dsmtuners.com/forums/newbie-forum/193052-checking-iac.html?highlight=iac+test

 

[twicks69]

If possible, do a boost leak, also, what are you using for tuning?

Are you recirculating your BOV?

Post a picture of your engine bay and we can always do the simple check of seeing if there is any obvious standing out to us.

 

[dahawkster]

I am also having the exact same problem please lmk know what fixes your car when you find out....

 

[stukyl28]

do you have aftermarket cams?

 

[SchroederGSX]

what it could also be is, that when your coming to a stop and throw it in neutral are you letting the turbo despool? because in my car when i hit boost and throw it straight to neutral (emergency only) the car will die. i have a feeling thats just a safety measure but i have no clue.

 

[twicks69]

No, it is not a safety measure. It is related to tune, or a problem that causes the car to more than likely to have too much fuel causing the stumble or shut-off or it is an idle speed controller issue that cannot compensate and the stepper motor isn't working properly.

Either way, I have my money on boost leak, or MAF overcompensation causing the stumble/shut-off.

 

[keviebaby]

what it could also be is, that when your coming to a stop and throw it in neutral are you letting the turbo despool? because in my car when i hit boost and throw it straight to neutral (emergency only) the car will die. i have a feeling thats just a safety measure but i have no clue.

I don't see how the car dying at speed could be considered a safety measure. Locked steering wheels and no power steering aren't exactly safer than when they are working.

I agree with Twicks that a boost leak or improper air metering should be to blame. Mine used to do this all the time around stop lights and my IAC was shot. I don't see that you have any way to tune the car. Are you still running the stock injectors or did you upgrade and not account for them?

 

[DSMnOOb00]

do you have aftermarket cams?

I Still have the Stock injectors, Cams and cam gears... at the moment I'm not using anything to tune but plan on getting DSMLink in the next few months..

I am also having the exact same problem please lmk know what fixes your car when you find out....

Will Do!

If possible, do a boost leak, also, what are you using for tuning?

Are you recirculating your BOV?

Post a picture of your engine bay and we can always do the simple check of seeing if there is any obvious standing out to us.

I have the Greddy Type RS recirculating back to the intake, I will post a picture soon..

altho to add a bit more info, I have my wastegate's vacume source off the intake manifold.. I was told to use a source closer to the turbo and then add a MBC inbetween them. Altho I dont really see this being the issue..

thanks

 

[97mitzugst]

I had this problem for a while and finally made myself a boost leak tester. It was a big leak right at the turbo. It ran great after that, but it's doing it again and I can't find any leaks and I'm pulling a code P0170 (Fuel Trim Bank 1). I'm trying to narrow mine down as well.

 

[DSMnOOb00]

<img src="http://i102.photobucket.com/albums/m82/raullags/photo-2.jpg" border="0" alt="1997 GSX"></a>

I had this problem for a while and finally made myself a boost leak tester. It was a big leak right at the turbo. It ran great after that, but it's doing it again and I can't find any leaks and I'm pulling a code P0170 (Fuel Trim Bank 1). I'm trying to narrow mine down as well.

What part of the turbo was leaking boost??

 

[2GFWDbeast]

This same problem happened to me when i upgraded the fuel pump. If you don't have anything to tune with, your stock ecu cant compensate fuel quick enough. Also if you have a lighten fly wheel computer cant keep up with with the fast rpm drop of a lighten fly wheel. I would definitely get some sort of tuning device such as safc or it you want all control get ecmlink. Tho you will need Eprom ecu in order to do the ecmlink. That was my issue, after i got a flashed ecu from dsmchips the problem went away.

This might not be your problem at all, theres other issue's such as iac out of whack, tps out of adjustment, dirty throttle body.

 

[97mitzugst]

I'm sorry. I didn't mean to make it sound like it was the actual turbo leaking. It was the coupler I had on the outlet of the turbo.

 

[DSMnOOb00]

I Think I'm just going to upgrade all my intercooler clamps to T-Bolt Clamps

 

[dsm4ever1337]

I have the same problem,

I actually had an accident the 2nd day i got the car..had the AC running..and it was humid...and i boosted..and when the turbo despoiled the rpm went so low that the car shut downed..and i was turning the steering @ the speed 80kmh and the steering got stiff and i hit the pavement..!! its kinda dangerous..still having the problem..and i have been running on the problem for almost a year..no one in my country knows how to fix it...

 

[DSMnOOb00]

just thought I would do a follow up, I replaced the piping and problem went away, it was a boost leak!

thanks guys!

 

[Spoolin92GSX]

Thank you for updating! I'm having what sounds like a very similar issue on my 1G, can I ask if you had any other symptoms? Power loss out of boost, sudden boost kick, rough idle? I'm trying to narrow down my problem as well. Thanks in advance!

 

[DSMnOOb00]

Thank you for updating! I'm having what sounds like a very similar issue on my 1G, can I ask if you had any other symptoms? Power loss out of boost, sudden boost kick, rough idle? I'm trying to narrow down my problem as well. Thanks in advance!

I add power lost after depressing the gas pedal

Rough idle (high)

Altho I never had a boost kick

I didn't think it was a leak at first, I had replaced every clamp with no results.
Then I just replaced the entire thing with hard pipes and problem went away

 

[my dreamt dsm]

Glad your car is working. Now see you around town.

 

[Spoolin92GSX]

I add power lost after depressing the gas pedal

Rough idle (high)

Altho I never had a boost kick

I didn't think it was a leak at first, I had replaced every clamp with no results.
Then I just replaced the entire thing with hard pipes and problem went away

Gotcha.. I'll be doing a BLT in the morning so we'll see what happens.. And congrats on getting your car back up!

 

[DSMnOOb00]

Well see said the blind man

Just got the car back, I was planning on smogging it next paycheck then I get this bull CEL! Had my seats ripped out of the car along with my boost gauge and rear view mirror!

It all happend over the labor day weekend.

Just got some junk seats and parts from a crashed gst, all I need now is smog, insurance n registration and I'll be ready to roll!

 

[DSMnOOb00]

Gotcha.. I'll be doing a BLT in the morning so we'll see what happens.. And congrats on getting your car back up!

Let's us know how things work out spoolin92

 

[Spoolin92GSX]

Well see said the blind man

Just got the car back, I was planning on smogging it next paycheck then I get this bull CEL! Had my seats ripped out of the car along with my boost gauge and rear view mirror!

It all happend over the labor day weekend.

Just got some junk seats and parts from a crashed gst, all I need now is smog, insurance n registration and I'll be ready to roll!

".. to the deaf mute." Damn that sucks man, kinda odd list to take but at least that's all they took. And I will definitely put up the results of the test, experience always helps and I haven't seen anyone else with my symptoms, so maybe it'll help someone else out there.

 

[DSMnOOb00]

any results yet?

 

[Spoolin92GSX]

Nope, took the chance to make a junkyard run for a bunch of misc. parts I need, then couldn't find my bike pump til it was dark (I'm working in a carport right now ) So I'm definitely doing it first thing in the morning.. I'm hoping it's just a loose/cracked vac hose, I need an easy fix haha.