I finally got my car back from getting GT28R and Walboro fuel pump done, everytime i accelerate to over 4500rpm the motor loses all power and jerks forward! The car used to rev all the way to redline without hesitation, now it chalked it up to being fuel cut but the way hits now feels more like the car is missing something. Any ideas??
Im still running stock MAF, injectors & ecu. If thats any helpful.
Fuel cut off at 4500rpm! Whats the problem now?
Re: Fuel cut off at 4500rpm! Whats the problem now? (JDMSIL80)
Do you have a boost gauge????JDMSIL80 wrote:I finally got my car back from getting GT28R and Walboro fuel pump done, everytime i accelerate to over 4500rpm the motor loses all power and jerks forward! The car used to rev all the way to redline without hesitation, now it chalked it up to being fuel cut but the way hits now feels more like the car is missing something. Any ideas??
Im still running stock MAF, injectors & ecu. If thats any helpful.
Re: Fuel cut off at 4500rpm! Whats the problem now? (Nowhere)
No boost gauge, my car is bone stock with only GT28R and fuel pump.
I just drove around and discovered more information on the problem.
If I use only partial throttle, it will let me rev higher up to 6000 without cutting on me.
But stepping on the throttle a little more, the boost/fuel would cut on me and the car jerks forward.
The power is unstable at full throttle and cut off early at only 4500.
At partial throttle, I could rev up higher but still cut off before hitting redline.
Whats seems to be the problem??
I just drove around and discovered more information on the problem.
If I use only partial throttle, it will let me rev higher up to 6000 without cutting on me.
But stepping on the throttle a little more, the boost/fuel would cut on me and the car jerks forward.
The power is unstable at full throttle and cut off early at only 4500.
At partial throttle, I could rev up higher but still cut off before hitting redline.
Whats seems to be the problem??
Re: (F3600)
The stock MAF is really that restrictive..
So even with stock ecu at 7psi, I have already maxed it out?
So even with stock ecu at 7psi, I have already maxed it out?
Re: (JDMSIL80)
How do you know you're at 7 psi? Get a boost gauge..
Re: (Nowhere)
I thought stock ecu only gives out 7psi?? correct me if I'm wrong...
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Dattebayo
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Yeah, this one has been discussed at length recently.
Did you search this one at all? Because I did and came up with a buncha threads that apply.
You sure do start alot of new threads and I see alot of people get pissed because of it. Its kinda like a whiny child nagging at its mother for candy or something. Can you just keep one thread or something? All we ever see anymore is your issues and it is kind of redundant to see them stck up one after another!!!
Did you search this one at all? Because I did and came up with a buncha threads that apply.
You sure do start alot of new threads and I see alot of people get pissed because of it. Its kinda like a whiny child nagging at its mother for candy or something. Can you just keep one thread or something? All we ever see anymore is your issues and it is kind of redundant to see them stck up one after another!!!
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[email protected]
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Standard injectors and MAF should be fine with that turbo up to about 14psi.
What you describe sounds like fuel cut. Fuel cut is a safety mechanism in the ECU to prevent engine damage on standard cars. When a certain engine load is measured by the MAF the ECU stops injecting fuel. Then when the load has droped below this limit it will inject fuel again. Fuel cut is usually quite violent - not a mooth cut at all.
An air leak after the turbo (between turbo and throttle body) can cause fuel cut - if air leaks out the MAF senses a very large air flow, the ECU thinks the engine is under a very high load and cuts the fuel.
What you describe sounds like fuel cut. Fuel cut is a safety mechanism in the ECU to prevent engine damage on standard cars. When a certain engine load is measured by the MAF the ECU stops injecting fuel. Then when the load has droped below this limit it will inject fuel again. Fuel cut is usually quite violent - not a mooth cut at all.
An air leak after the turbo (between turbo and throttle body) can cause fuel cut - if air leaks out the MAF senses a very large air flow, the ECU thinks the engine is under a very high load and cuts the fuel.
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float_6969
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You could have continued this in your previous thread that we had already been talking to you about all of this on. Regardless, as I stated in your other thread. It sounds like the MAFS is getting maxed out. The computer doesn't control the boost, the wastegate does. Are you sure you've got the wastegate vacum reference line hooked up? Do you have any leaks in the intercooler piping? Get a boost gauge and see how much pressure the turbo is creating. The stock MAFS is pretty restrictive, but I don't see it maxing out at 4500rpm at 7psi on that turbo.
Re: ([email protected])
I've checked and confirmed there's no leak after the turbo.What other things may cause the boost/fuel cut?
My car is actually faster with little partial throttle as I can rev higher.
Once I stomp into the gas pedal, there's no boost.fuel and cuts off really early.
My car is actually faster with little partial throttle as I can rev higher.
Once I stomp into the gas pedal, there's no boost.fuel and cuts off really early.
[email protected] wrote:Standard injectors and MAF should be fine with that turbo up to about 14psi.
What you describe sounds like fuel cut. Fuel cut is a safety mechanism in the ECU to prevent engine damage on standard cars. When a certain engine load is measured by the MAF the ECU stops injecting fuel. Then when the load has droped below this limit it will inject fuel again. Fuel cut is usually quite violent - not a mooth cut at all.
An air leak after the turbo (between turbo and throttle body) can cause fuel cut - if air leaks out the MAF senses a very large air flow, the ECU thinks the engine is under a very high load and cuts the fuel.
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boost_boy
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Re: (JDMSIL80)
If you've confirmed at your ecu that there's no codes, then safely assume your afm is probably faulting. But if you have not checked your ecu, you may want to suspect the TPS as well. There's a few variables that can also cause that issue, but my 1st guess would be the AFM, then the TPS or even a faulty knock sensor.JDMSIL80 wrote:I've checked and confirmed there's no leak after the turbo.What other things may cause the boost/fuel cut?
My car is actually faster with little partial throttle as I can rev higher.
Once I stomp into the gas pedal, there's no boost.fuel and cuts off really early.
Dee
Re: (boost_boy)
Does anyone know how much boost is the wastegate set at on GT28R?
Stock ecu has a boost/fuel limiter set at 10psi, Im thinking my wastegate might be boosting above this so thats why the ecu is cutting me off.
Stock ecu has a boost/fuel limiter set at 10psi, Im thinking my wastegate might be boosting above this so thats why the ecu is cutting me off.
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float_6969
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Re: (float_6969)
I have ordered the Blitz gauges (boost/temp/pressure) but they wont be here for another two weeks.
Just curious to know what Im boosting at the moment...
Just curious to know what Im boosting at the moment...
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float_6969
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Re: (float_6969)
Im gonna be getting a Blitz ecu with boost/fuel limiter removed and see if it solves the problem.
If it works and Im still running stock intercooler, is it safe to run at 14.7psi?
If it works and Im still running stock intercooler, is it safe to run at 14.7psi?
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NeedCAforS13
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NOOOOOOO. the stock intercooler is about as worthless as that crap I just took.
instead of paying for a blitz ecu, why not upgrade your intercooler? MUCH more worthwhile, seeing as you don't know what the Blitz ECU is tuned for! (regardless what the ebay seller says it is tuned for, they really have no concrete proof. Its not like its written on the ECU.
instead of paying for a blitz ecu, why not upgrade your intercooler? MUCH more worthwhile, seeing as you don't know what the Blitz ECU is tuned for! (regardless what the ebay seller says it is tuned for, they really have no concrete proof. Its not like its written on the ECU.
Re: (NeedCAforS13)
I already have the SSautochrome intercooler ordered, (it was purchased before the manifold otherwise I would have buy ARC). Hopefully its worth the price and function the way it should, and wouldn't screw up my motor!!
The Blitz ecu only costed me $130 shipped, wasn't too bad.
Looks like I should get install the intercooler installed before the ECU.
The Blitz ecu only costed me $130 shipped, wasn't too bad.
Looks like I should get install the intercooler installed before the ECU.
Re: (JDMSIL80)
Guys I have finally found the reason of the fuel/boost cut that I had previously.
So yesterday I replaced the stock filter box & resonator with a HKS intake filter. Mainly for the looks and sound, so I didn't expect much at all. As I was driving later that night, I revved it up just to see if it may sound any different. To my surprise for the first time the boost is kicking hard and I revved it to redline so quick that I didn't expected. It was wet on the road and my rear tires was spinning like crazy in 2nd gear, also for the first time I can hear the noise from the internal wastegate.
I cannot believe all that problem was caused by the stupid air filter!! I can finally make use of my brand new turbo!! The car feels a lot stronger with noticeable increase in midrange torque, and this is still with stock ecu!! Can't wait to put in my intercooler, manifold, downpipe and see the further improvement.
Thank you guys for all your help in this issue!
So yesterday I replaced the stock filter box & resonator with a HKS intake filter. Mainly for the looks and sound, so I didn't expect much at all. As I was driving later that night, I revved it up just to see if it may sound any different. To my surprise for the first time the boost is kicking hard and I revved it to redline so quick that I didn't expected. It was wet on the road and my rear tires was spinning like crazy in 2nd gear, also for the first time I can hear the noise from the internal wastegate.
I cannot believe all that problem was caused by the stupid air filter!! I can finally make use of my brand new turbo!! The car feels a lot stronger with noticeable increase in midrange torque, and this is still with stock ecu!! Can't wait to put in my intercooler, manifold, downpipe and see the further improvement.
Thank you guys for all your help in this issue!