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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Problem @4500 RPMS

  • Thread starter Thread starter 396LT1
  • Start date Start date Mar 18, 2006
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Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Mar 19, 2006
#21
  • Mar 19, 2006
  • #21
396LT1 said:
I can do that with my scan tool.. In the scan tool it reads that the frp is 6psi. But im still looking for a way to hook up a gauge when the rail has no service port.

Thank you Stang GT we will look into this tomorrow. It's a easy mistake that could of been made.

Would anyone happen to know the cost of the dual cobra pumps and the fuel tank?
Click to expand...


fuel rail presure reads 6 psi?? wow i bet the rail presure sensor is bad at 6 psi that thing would hardly run if it would run at all.
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
Mar 19, 2006
#22
  • Mar 19, 2006
  • #22
396LT1 said:
Im kinda new to this site so i hope i have this in the right section.. Im posting for my service manager at the shop i work at, he has a 01 mustang Gt thats been fully built for performance but seems to have a fuel delivery or spark issue when the car reaches 4500 Rpms. Im not a mustang guy so bear with me here. Here are the mods

4.6 Dss Supermod Level 10 racing motor
kenny bell twin screw blower w/intercooler @ 9psi of boost
DSS blower cam
DSS Racing Heads
42lb injectors
Ford focus Fuel pump
K&N Cai
75mm Tb
Bassani cats & catback
Ford Racing Shorty headers
B&M 5 speed Tranny
3.73 gears w/stock rearend
Unknown Fuel Management unit
Dyno tuning & Fuel Management unit done by Anderson Motors in Clinton, IL

Codes i pulled with my Snap on scan tool are random multiple misfire after i delete that code it will return in a couple of days, Not right away... Engine appears to run ok and not be down on power it dynoed 501rwhp but when you take it up to 4500 rpms or higher it seems like it's needing more fuel and not getting it. with my scan tool the FRP(psi) is 6psi and it reads that from idle to about 4k. Now i have attempted to check fuel pressure but on the fuel lines there isnt a port to hook a guage up to. So How do you check fuel pressure with a gauge? What should pressure be on stock 4.6? What would be Optimal pressure for a setup like above? If there is anything that you recommend checking, or can suggest i look into i would appreciate it. were trying to get the car runing to it's full potiential rather quickly for the upcomming racing season.
Click to expand...

I'd like a little more info on this problem.
1. Is he using the BAP along with the focus pump, or just the focus pump?
2. What is the symptom of the problem that made you look into it in the first place, if it appears to run ok, and isn't down on power?
3. When you say he is runing 6psi of fp from idle to 4k, is that only under WOT, or is that all the time?
4. What was the frp after 4k, or did you stop checking it at that point.
5. I assume the problem didn't show up during the dyno tune. Has the setup changed since then.

It does sound the the fuel pressure sensor may be the problem, but at that hp level I don't think the focus pump is enough.
 

MadDog2020

New Member
Jan 3, 2004
27
0
0
Kansas City
Mar 19, 2006
#23
  • Mar 19, 2006
  • #23
396LT1 said:
Would anyone happen to know the cost of the dual cobra pumps and the fuel tank?
Click to expand...

For my car's previous owner, it cost $370 for the fuel pumps and $190 to install them and modify the gas tank.
 
3

396LT1

New Member
Jun 1, 2004
29
0
0
Mar 19, 2006
#24
  • Mar 19, 2006
  • #24
jstreet0204 said:
I'd like a little more info on this problem.
1. Is he using the BAP along with the focus pump, or just the focus pump?
2. What is the symptom of the problem that made you look into it in the first place, if it appears to run ok, and isn't down on power?
3. When you say he is runing 6psi of fp from idle to 4k, is that only under WOT, or is that all the time?
4. What was the frp after 4k, or did you stop checking it at that point.
5. I assume the problem didn't show up during the dyno tune. Has the setup changed since then.

It does sound the the fuel pressure sensor may be the problem, but at that hp level I don't think the focus pump is enough.
Click to expand...

1.Yes he is using The BAP that came along with the kenny bell kit.

2. The car started hesitating at the rpm.. Like it wasent getting enough fuel.

3. That was with the car in neutral and the rpm was being raised steadly to 4500. My scan tool read 6psi all the way up to about 4k before i stoped. I havent taken the car out on the road yet with the scan tool hooked up.. Talk about running the motor too lean is keeping us from wanting to take the car up that high again.

4. Stopped checking but it was still at 6psi

5. The problem was noticed right after the motor and blower setup was installed that was still with the stock fuel pump as well. We thought the problem was because it needed to be tuned. Unfortunally i havent view the dyno sheet to see if it's appearant on the dyno sheet but i will.

*I Want to update on the mods list* The fuel management system is a IV PMS setup it was installed by anderson motorsports. If you have the latest 5.0 mag May 2006 edition it's on page 96.

Im going hook my gauge up through a T at the fuel filter and see what the psi is at. If anyone has a spec on what the stock fuel pressure should be so i can have a target range to be within i would appreciate it.
 
3

396LT1

New Member
Jun 1, 2004
29
0
0
Mar 19, 2006
#25
  • Mar 19, 2006
  • #25
MadDog2020 said:
For my car's previous owner, it cost $370 for the fuel pumps and $190 to install them and modify the gas tank.
Click to expand...

Are you still running the stock fuel tank? Is the 03 Cobra fuel tank a direct swap or is there some modding needed.
 

MadDog2020

New Member
Jan 3, 2004
27
0
0
Kansas City
Mar 19, 2006
#26
  • Mar 19, 2006
  • #26
396LT1 said:
Are you still running the stock fuel tank? Is the 03 Cobra fuel tank a direct swap or is there some modding needed.
Click to expand...

Yup, still running the stock tank. The previous owner of the car had the work done. I think it just involved removing a baffle of some sort.
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
Mar 19, 2006
#27
  • Mar 19, 2006
  • #27
396LT1 said:
1.Yes he is using The BAP that came along with the kenny bell kit.

2. The car started hesitating at the rpm.. Like it wasent getting enough fuel.

3. That was with the car in neutral and the rpm was being raised steadly to 4500. My scan tool read 6psi all the way up to about 4k before i stoped. I havent taken the car out on the road yet with the scan tool hooked up.. Talk about running the motor too lean is keeping us from wanting to take the car up that high again.

4. Stopped checking but it was still at 6psi

5. The problem was noticed right after the motor and blower setup was installed that was still with the stock fuel pump as well. We thought the problem was because it needed to be tuned. Unfortunally i havent view the dyno sheet to see if it's appearant on the dyno sheet but i will.

*I Want to update on the mods list* The fuel management system is a IV PMS setup it was installed by anderson motorsports. If you have the latest 5.0 mag May 2006 edition it's on page 96.

Im going hook my gauge up through a T at the fuel filter and see what the psi is at. If anyone has a spec on what the stock fuel pressure should be so i can have a target range to be within i would appreciate it.
Click to expand...

For the fuel pressure,
Engine Running 30-50 psi
Key On Engine Off 25-40 psi
Get the fuel pressure issue straightened out, and let us know if it was a sensor issue or pump issue. (I'm betting it is a sensor issue)

I'm not sure how much I would trust that PMS with it being a piggy back system, I'm not sure if would cause any kind of conflicts with and of the sensor operations. I looked at their website, and it doesn't look like it does anything that can't be done in the EEC so he might want to look into a different setup like SCT's pro racer package, and a wideband o2 setup.
 
3

396LT1

New Member
Jun 1, 2004
29
0
0
Mar 19, 2006
#28
  • Mar 19, 2006
  • #28
jstreet0204 said:
For the fuel pressure,
Engine Running 30-50 psi
Key On Engine Off 25-40 psi
Get the fuel pressure issue straightened out, and let us know if it was a sensor issue or pump issue. (I'm betting it is a sensor issue)

I'm not sure how much I would trust that PMS with it being a piggy back system, I'm not sure if would cause any kind of conflicts with and of the sensor operations. I looked at their website, and it doesn't look like it does anything that can't be done in the EEC so he might want to look into a different setup like SCT's pro racer package, and a wideband o2 setup.
Click to expand...

Thank you for the fuel pressure specs. Is there a better place to check pressure on a system without a port besides at the fuel filter area?

As for the pms system i believe it was recommended to him directly from anderson when they had it to do the dyno tuning.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Mar 19, 2006
#29
  • Mar 19, 2006
  • #29
396LT1 said:
Thank you for the fuel pressure specs. Is there a better place to check pressure on a system without a port besides at the fuel filter area?

As for the pms system i believe it was recommended to him directly from anderson when they had it to do the dyno tuning.
Click to expand...

a 01 should have a schrader valve, if not I would just go have him buy the adapter to plug in between the fuel line and rail.

and I agree with Jstreet about the sct pro racer package
 
3

396LT1

New Member
Jun 1, 2004
29
0
0
Apr 26, 2006
#30
  • Apr 26, 2006
  • #30
Update

*Update*

Jim The owner sent the car out to victor ford while on vaction to have everything over looked. Well They found that the fuel rail pressure was indeed 6psi like my scan tool read, the focus fuel pump that was installed was not a svt pump & the car was badly mistuned.. victor ford has since installed the dual cobra pumps & tank, upgraded the fuel lines, upgraded the fuel injectors, raised the rail pressure to 12 psi.. and removed the fuel management system and retuned the car.. It picked up 78rwhp and the misfire code along with the higher rpm cutout problem is gone.

We want to thank everyone that posted in this thread with the helpful information & tips I just wanted to let everyone know the update on the car.. He should be recieving it back within the next couple of days.

 

stangGT97

New Member
Dec 22, 2004
1,299
1
0
Boston area, MA
Apr 26, 2006
#31
  • Apr 26, 2006
  • #31
396LT1 said:
*Update*

Jim The owner sent the car out to victor ford while on vaction to have everything over looked. Well They found that the fuel rail pressure was indeed 6psi like my scan tool read, the focus fuel pump that was installed was not a svt pump & the car was badly mistuned.. victor ford has since installed the dual cobra pumps & tank, upgraded the fuel lines, upgraded the fuel injectors, raised the rail pressure to 12 psi.. and removed the fuel management system and retuned the car.. It picked up 78rwhp and the misfire code along with the higher rpm cutout problem is gone.

We want to thank everyone that posted in this thread with the helpful information & tips I just wanted to let everyone know the update on the car.. He should be recieving it back within the next couple of days.

Click to expand...

great to hear everything worked out!
 
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