I think im fuel cutting if anyone can help please do

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I think im fuel cutting if anyone can help please do

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I think im fuel cutting if anyone can help please do - 2/29/2008 6:03:41 PM

arielrojas

Posts: 17
Joined: 2/29/2008
Status: offline

I have a 98 GSX everytime i boost 10 or more pounds it feels like its cutting i think its fuel. i pressure cheked the line and im well within spec so i know its not the pump. also, im waisting too much gas way more htan normal a quarter tank will take me about 30 miles you can even smell it in the exhaust, unburned fuel. so i know im running ritch. i repleased front O2 sensor replaced plugs and wires replaced fuel filter and still doing it. and its not throwing any DTC's if anyone can give me some opinions i would aprreciate it

Post #: 1

RE: I think im fuel cutting if anyone can help please do - 2/29/2008 9:09:03 PM

Sebba

Posts: 13345
Joined: 2/20/2006
From: San Antonio, TX
Status: online

boost leak.

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Cheap + Reliable = Not Fast
Reliable + Fast = Not Cheap
Fast + Cheap = Not Reliable

I have found a median. I call it, DSM

(in reply to arielrojas)

Post #: 2

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 7:42:15 AM

TheEngineer

Posts: 10171
Joined: 1/25/2006
Status: online

i doubt its a boost leak cuz i dont think the car wouldnt boost right but this is more fuel. It sounds like something is telling it drop more fuel in and its overloading the injectors giving boost cut. Do you have a check engine light

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quote:

ORIGINAL: pilsenblue
Even tho My car looks great It will never be fast. Kinda like a hot girl that dosent give it up

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Post #: 3

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 10:47:46 AM

EMonz57

Posts: 10955
Joined: 5/13/2005
Status: offline

quote:

ORIGINAL: TheEngineer

i doubt its a boost leak cuz i dont think the car wouldnt boost right but this is more fuel. It sounds like something is telling it drop more fuel in and its overloading the injectors giving boost cut. Do you have a check engine light

hense a boost leak. a boost leak will make you run rich like that john. the car can run fairly normal even with a boost leak. I would suggest doing a boost leak test before anything since it is the cheapest and easiest solution.

Have you changed anything on the car prior to this problem starting??

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1993 Renn Red Supra Turbo 6spd

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Post #: 4

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 12:46:35 PM

Sebba

Posts: 13345
Joined: 2/20/2006
From: San Antonio, TX
Status: online

It will still boost that.... but with a lot more fuel in the mixture. A huge astronomical boost leak would prevent you from reaching that boost, and due to the massive change in a/f ratio, the car wouldnt even move.

Thanks Mike : )

_____________________________

Cheap + Reliable = Not Fast
Reliable + Fast = Not Cheap
Fast + Cheap = Not Reliable

I have found a median. I call it, DSM

(in reply to EMonz57)

Post #: 5

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 3:48:24 PM

EMonz57

Posts: 10955
Joined: 5/13/2005
Status: offline

well what happens on boost leaks is the turbo ends up working harder. and if the MAF is making readins for X amout of airflow yet some of that air is not making it into the motor then john what does that give you? added fuel for the MAF reading x amount of air. when that air is not present you burn extra fuel and run nice and rich ,you know that

< Message edited by EMonz57 -- 3/1/2008 5:15:33 PM >

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1993 Renn Red Supra Turbo 6spd

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Post #: 6

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 5:02:28 PM

Sebba

Posts: 13345
Joined: 2/20/2006
From: San Antonio, TX
Status: online

Yup

_____________________________

Cheap + Reliable = Not Fast
Reliable + Fast = Not Cheap
Fast + Cheap = Not Reliable

I have found a median. I call it, DSM

(in reply to EMonz57)

Post #: 7

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 6:45:07 PM

arielrojas

Posts: 17
Joined: 2/29/2008
Status: offline

I recently did a boost leak test and i couldnt find any leaks. alot of people tell me im fuel cutting and that i need to upgrade my fuel pump. but i dont think thats the case. I think this car should handle more than 10psi before it cuts. plus if it was the pump than why am i running extremly ritch. i tested my MAF sensor today. its good. im running out of options the only other thing that i think it might be is a bad ECU but i dont think so. i bought the car not too long ago and the bad thing is that the other owner was messing with the car and put all kinds of things into it and took everything off when he sold the vehicle. things would be alot easier if the car was stock. its got 3 inch downpipe full exhaust blowout vale boost control and i took a look at the ECU and i can definetly tell someone been playing with some wires in there. so i dont know what to do. Thanks alot guys for your comments you guys are great. keep them coming

(in reply to Sebba)

Post #: 8

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 7:11:26 PM

EMonz57

Posts: 10955
Joined: 5/13/2005
Status: offline

are you on the stock tuurbo? does it have an SAFC or anything. what type of boost controller does it have? Try lowering the boost controller all the way so its setup to run off the wastgate only and see.

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1993 Renn Red Supra Turbo 6spd

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Post #: 9

RE: I think im fuel cutting if anyone can help please do - 3/1/2008 7:30:27 PM

arielrojas

Posts: 17
Joined: 2/29/2008
Status: offline

i took off the boost controler and routed all the vacum hoses back to stock and every once in a while when i dont fuel cut i boost around 15-16 pounds. i think thats a little too much for a stock turbo. im not sure if its a stock turbo. but i think the waste gate should open up sooner than 15psi. i want to get a AFC to get the vehicle tuned but im not sure if that would fix the problem. but know that im reading some messages i think ive noticed that even when i boost ten psi the engine does not feel like a strong pull it it used to but i guess its cause air/fuel is all out of spec.

(in reply to EMonz57)

Post #: 10