I've had this happen to me a few times and Freaked the hell out me. Mostly in 3th or 4th gear , out of no where the car feels like it hits a Wall. My understanding from a search on evom is that this is a Fuel Cut off. I want to verify that this "feeling" is Fuel Cut. Boost is @21 around 4-5Krpm. I have basic boltons No tune. Planing a tune after Cam/pump install.

I've seen alot of FuelCut off but never saw how it "feels" when it happens.... so am I correct to say that Fuel Cut off feels like the car hits a wall ? thx

 

Yep, just like that.

 

Oh yeah....might be overboosting due to your basic bolt-ons...have someone with a tactrix cable raise the boost limits a hair to work around it for now until you get a TUNE!!!

 

Alright.. so could be fuel or boost. Either way nothing is broken LOL... I just need a tune very soon.

I have the Cam/pump just need to find one to install them. (only reason why they're not installed).

Alright thanks for the help I feel better now having an idea whats going on. FYI wideband was showing 10.5

 

I would like to know technically how does a fuel cut happen...

How does the ECU interpret the fuel cut necessity?

Is the EGT? Is the MAF? lambda? pressure?

I suspect that the stock fuel pump (Evo 8) becomes too hot when driving hard and temporarily decrease the amount of fuel causing a lean condition, then raising the EGT and throwing a fuel cut...

 

Well, here's why you're confused. There is no boost cut - only fuel cut. However, fuel cut is caused by running too much boost (sorta). The ECU is programmed to cut fuel if the MAF senses a certain max airflow. You reach this higher airflow not only by raising boost but by reducing taper. The reason why reducing taper is important is because we flow the most air at higher rpms, so your peak boost isn't what's important, but rather your sustained boost at high rpms. If you run enough boost at high rpms without a tune, you will hit fuel cut.

That's one of the reasons you should NOT be driving around modded without a tune while waiting on cams. You should get a basic $50 eflash for now, then get a custom flash when the cams are installed.

 

^^^ What he said!

TTP Engineering and Mellon tuning provide basic flashes for cheap!

 

I'm having the same problem.... going to install my walbro fuel pump tommorow so see any difference.

 

So is fuel cut something that is able to be removed with a reflash? Or is it a matter of just increasing the point at which fuel cut is reached?

 

with the cable/software you can fix your fuel cut problem

or

you can work with a tuner and they'll do it for you and fix the tune so that it gets the most out of your mods.

 

Huh? I suppose you didn't read what I wrote. Installing a fuel pump won't do anything except make you run richer. Get a tune and remove fuel cut - it's simple.

It can be removed.

 

You get an A for effort, but next time you would be better off just asking the question and getting the correct answer.

1. There is no sensor for which the ECU would be able to tell the exhaust gas temperature, nor is it any indication of the need to cut fuel.

2. The fuel pump does not overheat and drop pressure based on hard driving.

3. There is no hypothetical or actual lean condition that is measured by the ECU and to reiterate, no EGT sensor.

To answer the question. There is a preprogrammed "boost limit" which is LOAD BASED / ENGINE RPM. If the MAF frequency exceeds the level on the grid for the respective ENGINE RPM, then one would experience "fuel cut" as not to exceed that level.

When adding open air conical filters to the MAF sensor, the karman vortex signal is amplified at certain rpms and not only will that make the car add additional fueling as it is now hitting other areas of the fueling map, it will also reach the boost limit earlier.

Solution: Any time you change your intake system or increase the boost over factory levels, you should have the car retuned.

We offer this service under the mail in or eflash title available here:
http://ttp-engineering.com/catalog/p...roducts_id=265

 

depending on where you are in Tampa...make the drive down to TTP ..very good installs, and good price too...check their website...I promise the 45-1hr drive home will have you going "weeeeee" all the way home...

What cams do you plan on running? And other supporting mods too?

 

Well I have a few things to install. 272 cams, O2,LICP, Fuelpump and a tune. All the parts are sitting here cant find no one to do the work or tune it... ITs like my car has been blacklisted...lol

This was alot of info thanks.

 

get the parts installed and get with me for the tune when you're ready.