Anyone running boost with fuel injection please help!

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Anyone running boost with fuel injection please help!

Postby SamPartlow on Thu Aug 01, 2013 1:27 pm

I know theres gonna be some heavy hitters showing up this weekend and it looks like many of them are boosted. I really hope some of you see this and can help me with a problem I cant figure out.
When I start to build boost, the engine goes real lean and looses all power. The weird thing is that its not loosing fuel pressure. Ive recorded data with my aeroforce gauges and I dont see any drops in fuel pressure when it goes lean - the fuel rail pressure actually increases with boost as it should so I know my regulator is working properly. I tried back flushing the injectors to see if there was anything gunking them up, but this made no difference either. I logged MAF counts and there doesnt seem to be a problem there either, though I must admit I dont know exactly what values I should be seeing, but they do go higher and lower depending on how much air the engine is breathing so I assume its working properly. I just cant think of why this would be happening when there's not a fuel pressure issue. Does anyone have any ideas?
thanks
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby red_RPM_hatch on Thu Aug 01, 2013 3:49 pm

What all does your fuel system consist of? (injector size, pumps, etc......)

I imagine with the amount of power the car has, its been converted to a return style system instead of being returnless. You say the car isn't losing fuel pressure on your logs, how do you know its going lean? Via wideband? Have you pulled any plugs to read them?
red_RPM_hatch
 
Posts: 109
Joined: Tue Jan 23, 2007 4:14 am

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Thu Aug 01, 2013 6:15 pm

Fuel System: Sumped Tank -12 to Magnafuel 750 Fuel Pump (MP-4103=2500hp) Lethal Performance Stalker 340lph Intank Pump -10 line to Fore Fuel Rails -10 to Fore Regulator -8 Return to Tank Lethal Performance 105lb/hr injectors
The Aeroforce gauges' analog inputs are connected to a wideband o2 sensor and a gm 3 bar map sensor. All other information like fuel pressure and MAF count is logged through obd2.
Sorry I'm at work right now so I can't reply very quickly.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby red_RPM_hatch on Thu Aug 01, 2013 6:57 pm

Really curious what the plugs look like. Have you changed anything on it recently? Upped the boost without a retune? The plugs will help further show what you're dealing with. It's really hard to determine something like this through the Internet. With going lean and the fuel not dropping something has changed to where it's not getting enough. What RPM's is it leaning out at?
red_RPM_hatch
 
Posts: 109
Joined: Tue Jan 23, 2007 4:14 am

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Thu Aug 01, 2013 7:03 pm

I should add that I pulled the plugs and they show that it's running lean too.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Thu Aug 01, 2013 7:11 pm

The whole car was built and tuned and working perfectly Then it just started acting up a little at first and then progressively got worse and worse. I spent some time chasing other suspect problems before I finally figured out what was going on with the air/fuel when I logged boost and air/fuel together on one gauge while I logged fuel pressure on the other.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby red_RPM_hatch on Thu Aug 01, 2013 7:11 pm

Keep in mind with it being a twin turbo car exhaust/boost leaks will cause lean issues as well.
red_RPM_hatch
 
Posts: 109
Joined: Tue Jan 23, 2007 4:14 am

Re: Anyone running boost with fuel injection please help!

Postby red_RPM_hatch on Thu Aug 01, 2013 7:16 pm

What is the fuel pressure at?

How much does it go up through the RPM's?
red_RPM_hatch
 
Posts: 109
Joined: Tue Jan 23, 2007 4:14 am

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Thu Aug 01, 2013 7:23 pm

I have 5 different tunes for five different boost levels and it does the same thing no matter what boost level I run.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Thu Aug 01, 2013 7:27 pm

Fuel pressure goes up as the boost goes up I think it was like 77 psi when I was trying to run 21 pounds boost, but you can watch as the boost comes up so does the air fuel ratio. It's almost as if the computer isnt seeing the extra air and giving it more fuel like it should.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby red_RPM_hatch on Fri Aug 02, 2013 7:16 am

SamPartlow wrote:Fuel pressure goes up as the boost goes up I think it was like 77 psi when I was trying to run 21 pounds boost, but you can watch as the boost comes up so does the air fuel ratio. It's almost as if the computer isnt seeing the extra air and giving it more fuel like it should.



Do you have any logs to compare from when the car was running good to now? The more I think about it, something has gone or going south with your fuel system. If 77 psi was peak pressure I don't see that being enough. My car only makes a touch over 400 to the wheels and mine goes up to around 65-68 on a WOT pass in the upper RPM's.

It may be something as simple as a clogged fuel filter. Or you may have a regulator issue.
red_RPM_hatch
 
Posts: 109
Joined: Tue Jan 23, 2007 4:14 am

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Fri Aug 02, 2013 12:05 pm

Unfortunately I don't have any data logs. Idk if you've ever seen aeroforce gauges, but basically they are just small digital gauges that get their data through the obd2 port. They display two selectable values each, the values can be anything readable through obd2, or any add-on sensor like the wideband 02 sensor and 3 bar map sensor I have connected. You can set the gauges to record whatever they are displaying for something like 20 or 30 seconds, then you can go back and replay it later to see whats going on, but the data cant be saved to any kind of storage media, its just there on the display to look through until the next time you record a pull. That is all I have currently for logging data.
Fwiw, I've already changed my fuel filter and cleaned out my injectors and it made no difference. I'm beginning to wander if there's a problem with the custom MAF sensor. I know its sending a signal, but Idk if its in the range it should be in. It just makes sense that if there is extra air going into the engine that the computer isnt seeing, it would naturally go lean under boost. Too bad this thing couldn't just be an off the shelf unit cuz id try a new one.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby red_RPM_hatch on Fri Aug 02, 2013 12:26 pm

I know what an Aeroforce gauge is. I run their single unit in my car.

For reference if this were my car I would keep records of your logs to help diagnose problems like this in the future. Just keep them written in a note book. I really think it is a fuel pressure issue but no way of knowing since you have no logs from when the car was right.

How is the car tuned? Via a hand held or a chip? If it is a handheld you can also data log with it and it will actually give better details then the aeroforce.

I don't see your meter being the issue. What meter is it? I would guess its something like a Anderson Ford DBX meter or an SCT BA-3000.
red_RPM_hatch
 
Posts: 109
Joined: Tue Jan 23, 2007 4:14 am

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Fri Aug 02, 2013 2:47 pm

The meter is a custom unit from PRO.M racing.
Fuel pressure isn't dropping at all. It baselines around 55 to 60 psi as it always has, then increases proportionately as boost increases. That's what is so confusing about this, the fuel is there but the computer isn't giving it to the engine when it needs it. I haven't made any changes that brought this along either. It just started doing it on its own. Is it possible for the tune data on the flip chip To become corrupted? Or could my PCM be taking a crap?
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

Re: Anyone running boost with fuel injection please help!

Postby SamPartlow on Fri Aug 02, 2013 2:57 pm

Oh yeah I forgot to mention the car was professionally tuned and all of the tunes for different boost levels are loaded onto a Delta Force flip chip. It can hold up to 9 custom tunes and you just switch between them with a rotary knob switch. I don't actually have a programmer or software or anything. All I have is a burner that can load tunes onto the chip, but no tuning software.
04 Mustang Cobra
5.1l DOHC 32v Twin Turbo
T56 Magnum 6 speed
1,111 whp @ 27 psi on E85
Street legal, full interior, cold a/c, dvd navi stereo w/sub
SamPartlow
 
Posts: 25
Joined: Fri Jul 26, 2013 3:37 pm

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