Well, you can definately tell when it happens, usually feels like you're hitting a goddamn brick wall, your car bucks.

As for telling right before it happens, log your knock, IDC, A/F, etc. You'll be able to tell when it's gonna happen

 

unless your are obdII, you can throw knock and IDC out the window. your car will just sort of fall flat on it's face with lack of fuel.

 

I must have a freak car. No matter how hard I push it and how high the IDC's go, I don't seem to have ever hit "fuel cut".

 

Right after I install my Maft I started to get fuel cut. But only when its cold. It sucks! I have to be above 4K rpm to have it run right. Could it be spark blow out? Sold my logger and now I need one.! ha

 

Right after I install my Maft I started to get fuel cut. But only when its cold. It sucks! I have to be above 4K rpm to have it run right. Could it be spark blow out? Sold my logger and now I need one.! ha

Sounds more like spark blowout to me. Although I've never personally had that either. hehe

 

Thanks for the swift replys, but i feel i should explain myself better, I have a stock 94 GTO TT (with 93 electronics) I have just fitted an MBC and gauge and will be logging with TMO, I plan to log the following :-

- Air Flow
- Air Temp
- RPM
- Injector pulse width (duty cycle IPW x RPM / 1200)
- Knock
- Oxygen sensor
- Throttle position
- Timing Advance

I plan to turn up the boost 1psi at a time logging 3rd gear runs as i go.

My question is this, if i start to get knock i will see it in the log, so how do i no if i am getting near fuel cut?

 

My question is this, if i start to get knock i will see it in the log, so how do i no if i am getting near fuel cut?

As far as I know, you can't really tell when you're going to hit fuelcut til you do.

In my DSM, I used to hit fuelcut when I had horrible boost creep (wastegate pressure set to 10, then it'd creep up to 25psi). In my Stealth, the previous owner completly disconnected the wastegates, so it'd hit fuelcut somewhere around 15psi.

 

OK so its a matter of increasing boost untill knock or I hit the wall and then backing it off a bit.

Also should I tune when the ambient temperature is high or low?

 

You can log MAF frequency right? Fuel cut varies by RPM but 2000-2200Hz is on the edge. Above that you'll probably hit it.

 

You can log MAF frequency right? Fuel cut varies by RPM but 2000-2200Hz is on the edge. Above that you'll probably hit it.

Ah! That's why I've never hit it. My 9B's seem to max around 1600Hz. Of course, I should have plenty of fuel by turbo upgrade time anyway.

 

At 1600Hz you've got alot of fuel left over.

I see a hair over 2kHz at 29-31 psi.

 

At 1600Hz you've got alot of fuel left over.

I see a hair over 2kHz at 29-31 psi.

Been reading up on it. I think I'm just hitting the 1604Hz limit. Hits there around 4750RPM and holds it. Different MAF and fuel control in the future.

 

You can log MAF frequency right? Fuel cut varies by RPM but 2000-2200Hz is on the edge. Above that you'll probably hit it.

Cheers mate, thats what i was looking for.

 

you can also check your injector duty cycle, above 100%, you're most liekly going to hit fuel cut. I usually hit it at 105-110%

 

you can also check your injector duty cycle, above 100%, you're most liekly going to hit fuel cut. I usually hit it at 105-110%

Probably car-specific. I constantly run the piss out of my stock injectors and the log shows 125-134, which as I understand is 20 high, so that's 105-114% and I have never hit fuel cut.

 

EDIT: Forum sucks. That is all. Thank you.

 

I would recommend caution in that many loggers (TMO too I belive) can only display values up to 1600HZ. You can have numbers higher in the ECU but the loggers only show up to 1600HZ. If I remember correctly. So you will never really know from the logger if you are close.

The TMO manual likely explains this limit.

Best regards,
Sean

 

I would recommend caution in that many loggers (TMO too I belive) can only display values up to 1600HZ. You can have numbers higher in the ECU but the loggers only show up to 1600HZ. If I remember correctly. So you will never really know from the logger if you are close.

The TMO manual likely explains this limit.

Best regards,
Sean

Specs on the Scanmaster3 state " Engine Airflow, in Hz, this is the engine airflow sensor signal". Would this however suffer from the same 1604Hz limitation as other loggers? I'm curious if the Scanmaster displays the actual Hz value. Anyone know?

 

http://www.stealth316.com/2-rpmfuelcut.htm