Fuel Cut: What is it? How do I fix it? [merged]

In 3rd gear at 3000rpm, the car begins to hesitate and shudder. I can hear the turbo spinning and boosting way too much,very loud. I'm not sure if could be the wastegate or maybe the fuel cut is on because of the wastegate malfunction but I wanted any more helpful hints. The motor is strong with no smoke and with out a load it revs up fine but after driving it and hitting 3rd gear, it just starts.

it has new plugs,O2sensor,gaskets,hoses,..etc tuneups

 

That does not sound like fuel cut. You would definitely know if it was fuel cut. The car would not shutter at 3000 rpm. It usually hits at about 5000 and it's like hitting a brick wall. It could be anything from the clutch slipping to a lack of fuel flow or a lack of voltage flow..... Have a shop put it on an oscilloscope, that usually finds the problem quickly. I thought my wires were new, but I found out there was a burn spot from making contact with a hot area under the hood. The oscilloscope found it, Good luck...

 

I had the same problem a while ago.Turned out to be spark pluug wires.

 

plugs and wires for me caused the problem.

 

Okay I have a problem. I know some of you DSMtuners may have the same exact problem so I'm just trying to get mine out. Well, my question is how do i stop my car from hitting fuel cut? I went and bought an HKS fuel cut deal that makes it so it wont hit fuel cut, but my car still does. I top the car out at 140mph with fuel cut and I wanna know how fast my car would go with the damn thing hitting fuel cut. I'm pretty sure i hooked up the HKS thing right into the ECU. So now I'm stuck how to stop the motor hitting fuel cut. If anyone can Help, thanks.
-Rpmvulocity

 

Here .

 

I'm pretty sure it's the fuel cut because i can jus feel it. If my car was hitting the rev limit it will hit the rpm and jus stay there for awhile and rev in high RPM but it seems like it jus laggin so im sure it's hitting fuel cut.

 

I have a 97 GS-T, with stock fuel. At what RPM does the fuel cut occur.

 

And trust me, you'll know it when you feel it

 

I Havent seen anyone ask this question yet, sorry if someone already has but, I have a 1990 GSX with an ACV Controller removed airbox and exauhst system... I have been hitting 15-16lbs of boost acording to my aftermarket boost gauge. which is all good and dandy but just about the time I hit 16psi, I get that HORRIBLE FUEL CUT "BUCK" Does ANYONE know of any cheep fixes to get around fuel cut or even if its not cheap what i need todo, i hate being limited from my cars true potential that I know it is capable of if it would hit fuel cut. Thanks DSMers

 

any suggestions on new injectors and pump and afc? also is it possible to totally avoid fuel cut besides turning down boost, because we all know as DSMers, BOOST=SPEED

 

It is not necessarily caused by running lean. Lots of folks get fuel cut in the midrange (2800-4400 rpm) because the ecu senses that TOO MUCH air is going into the engine for that rpm, load, and throttle position. The ecu intentionally runs the entire powerband rich. But the airflow meter says to the ecu...hey, I have 500 cfm going by me. The ecu says...hey, that's too much air...the bov or the wastgate is stuck and the boost will destroy the motor...lets slow things down a bit...
contact these guys at http://www.technomotive.com. They are the best dsm ecu gurus around and can explain it way better than i can. BTW, a stock engine can be made to hit fuel cut with free mods.

 

I just hit a fuel cut the other night. I run a 16G with a VR-4 BOV and K&N Intake. I tool the car up to about 3500 rpm's in the third, and then just stepped on it. At about 4000 rpm I hit a fuel cut. I looke in the mirror to see if my tranny was behind me. Now I'm worried to take the car above 3000 rpm's. I couldn't find a fuel cut defencer for a 2G. Does anybody have any ideas. This guy is selling me a HKS fuel cut defencer, but the instructions say it fits 1G turbo eclipse. Please help.

 

This is the first time it happened since I had the turbo upgrade (about 4 months). Would a bigger pump be sufficient cause I don't have the money for new injectors or s-afc. What about some kind of fuel cut defencer.

 

Be careful with the FCD. If you are running into problems with feul cut and you have no feul management than gittin a FCD may ruin your engine. Start with feul management, set boost levels at conservative levels. The 16g is a high effeciency turbo that can likely boost hard and blow an engine, heck the 14b's can do serious damage by itself. Save up for some sort of feul management sys, and your buddys FCD wont work on your car, he has the k3 if he owns a 1g, you need the standard according to the HKS website.

 

What is the cheapest form of fuel management for a 2G, and the only FCD I could find of hks' website was the one for a 1G

 

safc is the most tunable and userfriendly for its price. You can go wit some used fcon units but it still not as tunable as the safc. HKS lists its three diff models, 1g DSM/supra, RX7, and everything else falls under standard. I would call HKS to confirm this to be sure.

 

Ok, I have an upgraded fuel pump, to go with my mods. When I go into 3rd and punch it, she starts to jerk.......again! Why is this happening? Could it be because I don't have upgraded injectors and S-AFC? Thanks for any input!

 

Jerks? From what I've heard fuel cut is like hitting a wall, your car basically just shuts down the fuel supply. Did it do anything similar before you upgraded the pump? check your plug and wires. Maybe a better description will allow others to help you better

 

It did this before the upgraded fuel pump, only worse. What it feels like it's doing, is choking, or pardon the expression.....coughing. I have new plugs and 8.5mm Magnacore wires. The harder I press the gas, the more it does it. When I slowly hit the gas, it doesn't do it. The jerk's are pretty rough, and begin around 5k rpm's. Very frustrating. Is that a better description?

 

i don't think its fuel cut b/c i have had it before. it hurts like a biaotch. when you have it you know it. you look in your rearview for your tranni. you might just have dirty fuel injectors.

 

uhm.. thats happening to my car when im cruising, new injectors, new fuel filter, new plugs/wires.. the only thing my mechanic can suggest is.. coil pack.. the engine not getting spark when it needs it.. so thats why im replacing next.. =\ and if it fixes it, that might be ur problem too.!

 

Sounds like it's an ignition problem...i think a DIS-2 is in your future. My car suffered the same symptoms that you described until i threw in the DIS-2...I pull smoothly to redline now.