Fuel Cut: FAQ....

[MSP#735]

Ok guys/gals i recently installed a MBC (JoeP) and i am having problems with it and its pissin me off...

Fuel cut occurs almost every time i go into 3rd gear around 3K RPM! (bang)

If i get a FCD, will this is in anyway harm my engine/turbo? I am only gonna boost 8/9 PSI WITH supporting mods....

Why exactly does Fuel Cut happen?

Anyway that you can alter your driving conidtions and NOT get fuel cut or is a FCD the only way to rid this bulls*** problem??? (dunno)

THANKS!!!

 

[Metal MP5]

depends on the amount of air that's passing through your MAF sensor. depending on that, your MAF sends a voltage signal to your ECU which cuts ignition at a certain point to avoid problems ... the FCD will let the voltage raise and stop it at one point and keep it going at the same level. this will hurt your engine if you boost too high or in the event of a boost spike ... but if you stay at 8-9psi, you should be fine (intake and intercooler are a VERY good idea if you are gona do this)

i ran 10psi all summer and the car still runs great

contact Turfburn about an FCD, he has a great one coming (i tested it)

 

[MSP#735]

how much is Turfburns FCD?? i DONT have a FMIC though, i DO have the Injen CAI....like i made mention i plan on runnin no MORE than 8 PSI year round........is this the spool control or the wastegate creep?

 

[Metal MP5]

none of those, its the Fuel Cut Defenser

i guess 8 or 9psi will be ok without the FMIC, but the thing is, you have nothing colling down the air on it's way to your engine. that's why the FMIC (or upgraded SMIC) is important. but it's more expensive ... it's up to you. i'm sure alot of people are running that amount of boost with no FMIC and are doing just fine

there is no price on the FCD yet since it was not officially released yet

 

[Brian MP5T]

Subscribing...

 

[MSP#735]

this is definately an issue that i am going to have to rid......i love the extra boost but if its gonna jeopardize my turbo/engine.....then im gonna remove the MBC....boost spike is another BASTARD of a problem that i am having spiking to 10PSI.....damnit will the madness and bulls*** EVER STOP?????

 

[BlkZoomZoom]

lol.

Take the mbc off if ur skeered of breaking anything. You have to be able to pay to play.

 

[Metal MP5]

you will get boost spikes with an MBC for sure

since i got my exhaust, my stock boost is a little under 9psi ... without even using my boost controller, my boost spikes at around 0.90bar all the time, then goes down to a solid 0.60bars (8.7psi) ... but sometimes when it's cold and the car is not warmed up completely yet, i will spike over 1bar ... i've hit 1.2bar before (17.4psi) and my engine is still alive

it probably hates me ... but it runs fine. the clutch is gone though
on the other hand ... my friend had a 17psi boost spike on a stock motor with CAI/FMIC and MPI running rich and bent a rod. you're never safe

if you dont wana have problems with your car, don't change anything. like blkzoomzoom said, you have to be able to pay to play

 

[MSP#735]

Hmm so what to do, what to do?!?! damn this sucks......

 

[Metal MP5]

HP is expensive with this car, unless you can do the whole thing yourself (bend your pipes for an exhaust, weld, etc)

You have to take it in stages if you don't wana pay for an engine rebuild ... CAI/SRI being the 1st thing you should do then i think an upgraded intercooler is required. From there, your air intake and air temperature is taken care of ... at that point, i would up the boost a bit.

I wouldnt play with boost before having those 2 parts installed ... but that's just me. I just really didn't wana have to deal with a blown engine, so i did those 2 before upping the boost, and i had my electronic boost contorller the whole time ... it was hard to resist =)

 

[FlyinMSP]

Personally I think the no. 1 thing to do is the exhaust if that's not already done. It's a relatively cheap mod and there are quite a few poney to find in there! I wouldn't mess around with a FCD unless there's some better fuel management. It's there for a reason! Then, of course intake and a better intercooler (nor necessarily a FMIC). As for the intake, no need to spend mega $$$ for something flashy, but that's my opinion
Finding the right setting with a MBC is kinda hard cuz by their nature they're crude devices.
my 2 pennies...

 

[MSP#735]

hmm well since i really havent stated my supporting mods ill go ahead and do so and you guys can make from them what you think....and how much i should boost ect.

2.5" flow Apex DP with high flow cat
NGK plugs (one step colder)
Injen CAI
JoeP MBC (set at 8PSI...for now atleast spiking to 10PSI (bang) )
(FCD possibly, if i keep this pace up.....fuel cut and all)

 

[STAR 80]

No where in your "supporting Mods list" do you have any form of engine management or intercooler.

Uping the boost on a stock car with no front mount or upgraded side mount will net you engine damage before any real performance gains. Simple as that.

Doing any boost change to this(especially) or any car without proper engine managment is really asking for it. One could hardly call a DP, some plugs, oh and a CAI Supporting Mods, When in fact if you were to of saved the money and bought a afc instead you would probly be netting higher numbers than with those mods on a stocker.

And you mentioned that, this is all really pissing you off. Jesus, Man, do some research before you blow your engine and come back to the boards bitching on how the FS sucks and Mazda sucks cause thay are not going to cover it.

Don't mean to sound like a dick, cause I'm not trying to be, but really If you love the car do it right. Get you some fuel managment, free up the exhaust from the turboback, and a front mount. Do these and you will be very proud of what you have, and then you can safely move forward towards the balance between performance and reliability. Good luck bro.

 

[MSP#735]

well s***! guess i better sell the MBC then huh? defintely not ready to drop $550 on a SMIC (rite now atleast) or i COULD hold on to the MBC, wait til i get the SMIC....oh, ill probably need a FCD too.....Hmm im such a dumbass!! thanks......

 

[BlkZoomZoom]

star 80- 13.15 @ 105 w/ the stock pipes and intercooler........I guess I haven't gotten any performance gains yet....I can't wait!!

 

[yashooa]

No offense Star 80 but you are a dumbass. My car is verifiably faster at 13PSI even with the stock IC than it was at stock boost.
I would like a new SMIC but even without it the raise in pressure has had a very positive effect of my car's performance.

 

[Uturnman]

well s***! guess i better sell the MBC then huh? defintely not ready to drop $550 on a SMIC (rite now atleast) or i COULD hold on to the MBC, wait til i get the SMIC....oh, ill probably need a FCD too.....Hmm im such a dumbass!! thanks......

Easy there Jeff, you don't need sell anything. If it worries you that much then remove the MBC for now until you can at least get a FCD. Then install both at the same time. Be aware that fuel cut will get worse as the air temperature gets colder. Remember that BLU has been running with the MBC and FCD for over a year at 10 psi with an otherwise stock car and has not had any problems. You just have to avoid doing stupids things, like flooring the car from low rmps in 3rd, 4th or 5th, for example.

 

[Metal MP5]

the big difference you will notice when upping the boost with the stock IC is that as you go, it won't pull as hard as it did when you started the car. I was loosing about a tenth of a second every run at the track with the stock IC, up to about 0.5sec

stock, i would run a 15.4 then drop to about 15.9/16 after a few runs

 

[MSP#735]

Easy there Jeff, you don't need sell anything. If it worries you that much then remove the MBC for now until you can at least get a FCD. Then install both at the same time. Be aware that fuel cut will get worse as the air temperature gets colder. Remember that BLU has been running with the MBC and FCD for over a year at 10 psi with an otherwise stock car and has not had any problems. You just have to avoid doing stupids things, like flooring the car from low rmps in 3rd, 4th or 5th, for example.

yea that is true i think what im gonna do is lower the boost for know to around 7 ish and wait for Turfburns FCD to come out and put that one on....looks promising so we will see...as for hitting fuel cut....i ALWAYS hit it shifting from 3rd to 4th at 3500+ RPM...kinda odd. im tryin to "relearn" how to drive the car now, kinda difficult though....

oh, hows the car comin? is she all done? id love to see her and see how she runs!

 

[STAR 80]

I work closely with one of the fastest MSP's to ever hit these boards. I know exactly what upping the boost on the MSP changes, stock or otherwise.

I also have been tuning forced induction vehicles for almost 15 years. But, I'm the dumbass eh?

I was mearly trying to help the guy. as was everyone on this thread. But I guess you guys showed me huh. lol

And Blkzoomzoom, props to your accomplishment with the stock setup, I follow your progress rather closely here. Ups and downs. And you know first hand what a blown FS looks like, there be it almost intentional.