Possible way to raise fuel cut limit ??

[jamiep]

Hey guys, this maybe a total noob question but i cant find an answer by searching.
From what i have read on here, fuel cut seems to be determined by volume of air flowing thru maf sensor (correct me if i'm wrong). If i wind the bypass screw back on the maf sensor (the one under a blob of silicone) and allow a bit of unmetered air thru, would this not fool the ecu and as well as leaning the mix out, wouldnt it raise the fuel cut limit ?? I have already wound the restricter screw out and there is a definate increase in power and a slight boost increase but as i have removed my boost controller not sure if it will affect fuel cut yet and the weather in wales in not permitting me to tinker......if only i didnt have a broken V6 sport clogging up my garage lol

Thanks ppl

[aboo]

Only way to raise fuel cut safely is by flashing the ECU.

[jamiep]

Only way to raise fuel cut safely is by flashing the ECU.

So what i said wont fool the ecu then ?? Found it as part of a tuning flow chart by road runner racing(?) for leaning out the AFR.

[aboo]

Not that I know of. I have done the MAF mod & I didn't notice much difference. If you want to mess about with the AFR's you'll need something like a Innovate MTX-L Wideband Gauge.

[jamiep]

Yeah as it stood it was running quite rich so i leaned it out on trial and error but it seems to be running much smoother, a little lumpy at idle but i can live with that. Next purchase will be a gauge so i can optimise it. Thanks for the quick reply tho dude

[BraindG]

Don't do the MAF mod, it's proven to increase knock dramatically - for proof please see my "removing the knock" thread.

Get it back to normal ASAP, only once you have facilities to flash an ECU reconsider this.

[Kryton]

Remap or fcd. Foxdie can help with the remap or I have a hks fuel cut defender here for £35

[jamiep]

Excuse the noobness but im completely new to tuning petrol turbo cars. So would i hear knock or something as the car has never run better since i done the mod. Will take ur advice and wind it back to where it was until i get an AFR gauge and lean it out properly via ecu.

[jamiep]

Remap or fcd. Foxdie can help with the remap or I have a hks fuel cut defender here for £35

How does the fuel cut defender perform, does it make sizable increase to fuel cut limit. Looking to set boost to around 14psi at the moment so would it allow for that much of an increase.

Running at 11 psi with maf sensor modded, runs at 8psi stock.

[Kryton]

The HKS FCD is an electronic device developed to properly raise the factory fuel cut level on factory
turbocharged vehicles.

As modifications are made to optimize engine performance , the factory fuel cut is often triggered by higher boost levels
which activate a fuel delivery cut-off as a failsafe procedure.

Symptoms of fuel cut are hesitation, bogging, and/or illumination of disgnostic indicators.

The electronic signal from the FCD will raise the fuel cut level to accomodate for the additional boost without triggering
fuel cut and/or an engine diagnostic light. The FCD installation is designed to be easily integrated with the VPC/F-CON or
factory ECU harness.

[foxdie]

How does the fuel cut defender perform, does it make sizable increase to fuel cut limit. Looking to set boost to around 14psi at the moment so would it allow for that much of an increase.

Running at 11 psi with maf sensor modded, runs at 8psi stock.

Hi Jamie,

A fuel cut defender "clamps" the amount of air being reported to the ECU, so you could be boosting at 1.3 bar and the ECU will only see 0.9, FCDs are a good way to get around fuel cut but if mistreated and set up incorrectly, they could cause problems. Generally though, they're good value for money and do their job (let you boost a little more).

ECU tuning however can not only raise fuel cut, but also adjust boost to whatever you desire (within safe boundaries), without the need for a boost controller, although a boost gauge would help for monitoring (as the ECU can on very rare occasions boost-spike, this is generally dealt with by good mapping and safety margins). Speaking of remapping, I'm based in South Birmingham (so not too far away) and typically charge around £60 for a remap and can do every VR-4 ECU, even pre-facelifts

Kind regards,
Jason

[jamiep]

Awesome explanation guys thanks. @Jason Im actually taking a friend to warick to look at an mr2 next weekend, a sunday probably so maybe i could swing by and let you loose on the ecu if its convenient for you.

[foxdie]

Awesome explanation guys thanks. @Jason Im actually taking a friend to warick to look at an mr2 next weekend, a sunday probably so maybe i could swing by and let you loose on the ecu if its convenient for you.

Unfortunately I'm visiting family that weekend, but do have all of the following week off? Friday the 31st I'm at Atiks working on his car in Wednesbury?

[jamiep]

Unfortunately I'm visiting family that weekend, but do have all of the following week off? Friday the 31st I'm at Atiks working on his car in Wednesbury?

No worries, im not guna have chance the following week so i'll definately catch up with u soon and arrange something. Thanks dude.

[Davezj]

If you have a flashable ecu then raising fuel cut level via an ecu reflash is definitely the bet way to go. And Jason has the gear to do any AFR the 3 variations of vr4 ecu.