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Discussion Starter · #1 ·
Allright, so first off i have a s13 with a redtop swap, fmic, 3 inch exhaust, and a walbro 255.

So heres what happens, I can be driving fine in everyday driving, but when i step on it, an really get it to make high boost it will just die, almost like a fuel cut

it wont hit rev limiter, it will just die. ill have to wait a about 9 or more seconds to even get throttle response. im soo lost on this.

llast night i was at the drag strip. and launched in first and as soon as it high boost it just cut out. engine still idleing but just no throttle response, i waiting about 8 or more seconds for it to get back to having throttle response and i ended up making it back down the track but for an amazing time of 24.55! woooooo

someone please help me haha

thanks
 

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How long has it been doing this for? Is it happening when your shifting or is it only when it hits high boost "around 3500 RPM"?
 

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Discussion Starter · #3 ·
since ive basically finished the swap,

i replaced spark plugs today and it didnt fix anything, switched out MAF with my buddies blacktop MAF and didnt make a difference, im stumped
 

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Discussion Starter · #6 ·
turboxs MBC, and 10psi, stock sr MAF


and highboost i mean like full throttle around maybe 6000rpm or more(havnt done cluster swapp yet!)

It doesnt do it all the time though, when it happens it wont diie, the car will still stay on and then if i put the clutch in and bring it back down to idle then ill have throttle response again
 

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turboxs MBC, and 10psi, s

and highboost i mean like full throttle around maybe 6000rpm or more(havnt done cluster swapp yet!)

It doesnt do it all the time though, when it happens it wont diie, the car will still stay on and then if i put the clutch in and bring it back down to idle then ill have throttle response again
I would probably be suspect of a bad throttle position sensor or its wiring....
 

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Im just wondering, how come you put in a fuel pump? I was thinking it could be your injectors, you know high flow pump but stock injectors. But if everything is stock then no need for a walbro pump stock ecu can handel 12 psi with no mods.
 

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Discussion Starter · #10 ·
whats your plug gap?
im running the NGK bkr7eix so therefore, no gapping


And the reason for the fuel pump was because i figured that it was dying because lack of fuel, so i upgraded, hoping that would fix the problem. but turns out it didnt.

I was reading up on some things, seeing at some people refer to it as boost cut? or even that my maf may not be large enough, but i dont see how thats possible because it would happen to more people then just me.

Seeing as a bad TPS my car would idle highw without my foot on it or even bog out or stall at idle? i coulld be wrong just what ive read.

im getting sick of this porblem!
 

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Unless you have a leak in the boost line to your gauge? This leading you to believe your making 10 psi when you could be making more...this is honestly, a guess!

Oh and as a quick test on the theory of the tps ...unhook it and drive around to see if anything changes...real easy cheap test. :)
 

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Not the hijack your thread or anything. but Im having the same problem. same mod. but this never happen to my t25. only when i put the gt2560r on. but its only happens at the top of my 3rd gear and 4th. never 1st or 2nd. Im running stock boost. :(
 

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Discussion Starter · #13 ·
Not the hijack your thread or anything. but Im having the same problem. same mod. but this never happen to my t25. only when i put the gt2560r on. but its only happens at the top of my 3rd gear and 4th. never 1st or 2nd. Im running stock boost. :(

alright so, think ive narrowed it down to 2 things, electrical, or the one im more sure into the problem being is a boost leak, blowing a coupler off at higher revs.

as the boost hits during higher rpms it causes a coupler to blow off, since being in gear there is still boost being fed but because the coupler blows off there is no throttle response.

its only until you bring the car down to idle rpms that you will have throttle response again. becuase the coupler becomes a closed circuit now.

someone correct me if im wrong but its just my .02
 

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Need more fuel (injectors, Z32 or equivalent MAFS, computer and tune)

Try this:

1. set your boost back to stock and give it a try and let us know what happens.

3. then if you have a way to check the voltage drop at high boost (may have something there)

pretty sure your not getting enough fuel.


rev your car from the engine bay if you have a loose coupler you would notice.
 

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Not the hijack your thread or anything. but Im having the same problem. same mod. but this never happen to my t25. only when i put the gt2560r on. but its only happens at the top of my 3rd gear and 4th. never 1st or 2nd. Im running stock boost. :(
Need more fuel and better airflow management. The volume of air drawn through the airflow meter will be greater on the 2560r verses the t25 at stock boost. The 2560r may be calling for your ECU (A/F Ratio) to stretch the stock 370cc's to their max (30% over) which is well out of their efficiency range.

Or the stock SR20DET MAFS voltage signal range can not cope with the 2560r on throttle (top of my 3rd gear and 4th).

My advice:

injectors (555cc will cover you), Z32 or equivalent MAFS, computer and tune and please :bawling: don't keep doing this to your motor cause if you starve it of fuel on load she may blow.
 

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Discussion Starter · #16 ·
Need more fuel and better airflow management. The volume of air drawn through the airflow meter will be greater on the 2560r verses the t25 at stock boost. The 2560r may be calling for your ECU (A/F Ratio) to stretch the stock 370cc's to their max (30% over) which is well out of their efficiency range.

Or the stock SR20DET MAFS voltage signal range can not cope with the 2560r on throttle (top of my 3rd gear and 4th).

My advice:

injectors (555cc will cover you), Z32 or equivalent MAFS, computer and tune and please :bawling: don't keep doing this to your motor cause if you starve it of fuel on load she may blow.

very understandable. its weird thing, hasnt done it since for me. my walbro is giving it enough fuel so i know its getting fuel.

but i am looking at getting a tune, but from where i live, the question is "where?!?!" i am going to upgrade my injectors, MAF and to a t28

just need to find a tune!
 

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if your motor cuts out when you're at wide open throttle check all your lines and see if they didnt accidently pop off during max boost. I blew a vac line off the nipple and my car died spontaneously like yours did. unless you're mechanically savvy and know what you're doing. just thought I'd mention though.
 
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