Hittin fuel cut at 9psi......Why...?

[TBMSPED]

So I guess I need to get a fuel cut block, and the MSP has been flashed. But I know it is the cut because of the massive shut down of the engine. Has anyone else had this problem?

 

[03.5YellowMSP]

yeah iget that too. its happens becasue it is getting cold out.

 

[TBMSPED]

How.....?

Whats the cold have to due with it? So it wont do it in the summer?

 

[BremertonMSP]

Re: How.....?

Whats the cold have to due with it? So it wont do it in the summer?

Theory is, with the denser air the MAF sees more air at a lower PSI. Once the threshold is reach, fuel/spark cutoff is triggered. That's why you may not see fuel/spark cut at 9psi in the summer.

 

[TBMSPED]

So How...

Do you get around that....get a fuel cut block?

 

[03.5YellowMSP]

When the air gets cold it becomes more condensed. As the cold air passes through the MAF sensor the ECU tells the car it needs more fuel. If the car cant put enough fuel in which would cause the motor to lean out. This is when it cuts and causes I sudden lose of power. It is just the ecu trying to protect the motor. FCD will get rid of this cut but you must be careful that you dont boost too much or it will lean out and then BOOM.

 

[TBMSPED]

Got ya...

What about putting somthing on there to add more fuel?

 

[03.5YellowMSP]

A complete stand alone unit would be perfect. Those can be expensice from what I have heard. If you got the cash I would say that would work best. I think there is S.D.S. is a good one.

 

[turboge]

Or a haltech.....

 

[t3ase]

Or you could do as many people do and turn the boost down when it gets cold outside to protect the engine/turbo.

 

[jersey_emt]

Yeah, I was running 9psi for a while, but now it's back to stock because of the fuel cut.

Stock 7 psi at cold temps is almost as fast as 9 psi in warm/hot temps.

 

[t3ase]

exactly

 

[spoolup]

So what if you got bigger injectors.....will that stop it from leaning out?

 

[Jeph]

You can't just add bigger injectors, you'd need a way to control them. Your ECU isn't going to know what to do if you just add bigger injectors. A piggyback, or Standalone is the only way to go if you don't want to hit the "spark cut"
I think Perf stated there was no such thing as a fuel cut, and it was caused by the MAF being maxed out. Too much air...

 

[Dexter]

why would you want to CUT fuel. that makes LEAN. that means YOURE ******.

 

[Jeph]

Hence the "there is no fuel cut" comment

 

[vodapas77]

So any guidance on running a FCD? I got Joe P's and his MBC. I live in Hawaii so I don't have to worry about the cold. How much boost can I run on a flashed car with an FCD before I start running into the danger zone? I want to spike at 12 and then down to 10-11 psi range. Is this safe in constantly warm weather or too high?

 

[MazdaDryvr]

If I turn the MBC all the way closed will that return things to stock boost or will that shut the boost off completely?

 

[azian6er]

^ it will be stock boost

 

[MazdaDryvr]

you are 100% certain?