Fuel pressure falls under boost...
01-14-2009, 12:29 PM
#21
4th Gear Member
Join Date: May 2006
Location: Fort Mcmurray, Ab
Posts: 1,126
If I plug in the factory connector into either FPDM, the car runs and drives.
The FPDC still maxes out at .500 with any sort of aggressive throttle input.
Here's everything I've tried so far to get this to work properly:
http://www.modularfords.com/forums/s...99#post1292999
The FPDC still maxes out at .500 with any sort of aggressive throttle input.
Here's everything I've tried so far to get this to work properly:
http://www.modularfords.com/forums/s...99#post1292999
I tried doing that too, the car ran on both modules with the first connecter, but when you take off the first connector and leave the second one in the car will slowly die...
This was the thread I started.
https://mustangforums.com/forum/4-6l...f-problem.html
01-14-2009, 02:39 PM
#22
3rd Gear Member
Thread Starter
Join Date: Dec 2007
Location: Coral Springs, Florida ~ 33076
Posts: 608
I'm, sure your having the same problem as me, just a little different because of the kit.
I tried doing that too, the car ran on both modules with the first connector, but when you take off the first connector and leave the second one in the car will slowly die...
This was the thread I started.
https://mustangforums.com/forum/4-6l...f-problem.html
I tried doing that too, the car ran on both modules with the first connector, but when you take off the first connector and leave the second one in the car will slowly die...
This was the thread I started.
https://mustangforums.com/forum/4-6l...f-problem.html
I just read the thread and we're seeing the EXACT same symptom. That leads me to believe it's a wiring issue.
What I'm struggling with is that I feel like I've checked every wire, every where I can find a wire.
I simply don't know what or how to check any more.
What is the data wire you mentioned?
Oh, and if I plug in the second FPDM harness (the new add on) the idle quality goes to crap. Again, this points to wire issues, but I've still got no results in tracking this down.
*grrrrrrr*
01-14-2009, 06:54 PM
#24
6th Gear Member
Join Date: Sep 2006
Location: Gainesville, FL
Posts: 11,278
My car handled it pretty well, when I first got the ***** to bring the car past 3000rpms with the supercharger on, and started loosing fuel pressure, it was almost like traction control kicked in. It felt like the car knew before I did and it did something so I didn't blow up. Almost like the car wouldn't allow the blower to reach past 5 psi... I know pretty well that if that happened in some other cars, you could say goodbye to the motor.
01-15-2009, 11:25 AM
#25
3rd Gear Member
Thread Starter
Join Date: Dec 2007
Location: Coral Springs, Florida ~ 33076
Posts: 608
I have a copy of the diagram above, but my wires are different from what's shown.
The layout is the important thing.
In another thread, someone made the following suggestion:
The layout is the important thing.
In another thread, someone made the following suggestion:
Originally Posted by 05Stroker
While datalogging the FPDC unplug the fpdm connectors one at a time and note the fp dc with both connected and what it is when you disconnect each fpdm connector. Dont swap them but disconnect one at a time. Also with the car running at idle ck the voltage on to the fpdms on the connector at the pin 5 location. This is the power in to the fpdm. If you have power here then ck for voltage at pin 4 , this is the power out to the pumps. If there is power there then go back to the fp connector in the car and ck pins 3 and 4 for voltage. All this has to be checked with the car running at idle.
01-15-2009, 02:14 PM
#26
3rd Gear Member
Thread Starter
Join Date: Dec 2007
Location: Coral Springs, Florida ~ 33076
Posts: 608
Here's what I came up with:
When both FPDMs are plugged in the X3 shows a value in the high .37X range.
When you unplug the connector from the second FPDM the value does not change.
When you plug in the second one, but remove the OEM FPDM plug, the value immediately jumps to .500.
Checking the pins in the actual FPDM connections, as well as the fuel pump connection under the seat returns the following values.
When both FPDMs are plugged in the X3 shows a value in the high .37X range.
When you unplug the connector from the second FPDM the value does not change.
When you plug in the second one, but remove the OEM FPDM plug, the value immediately jumps to .500.
Checking the pins in the actual FPDM connections, as well as the fuel pump connection under the seat returns the following values.
01-15-2009, 03:12 PM
#27
6th Gear Member
Join Date: May 2006
Location: Nicely done
Posts: 11,881
01-18-2009, 08:33 PM
#28
3rd Gear Member
Thread Starter
Join Date: Dec 2007
Location: Coral Springs, Florida ~ 33076
Posts: 608
After careful review.... 
I'm thinking it's a dead pump. I'm going to pull the assembly this week and test them individually. I'll let you guys know what I come up with.
I'm thinking it's a dead pump. I'm going to pull the assembly this week and test them individually. I'll let you guys know what I come up with.
01-18-2009, 08:43 PM
#29
1st Gear Member
Join Date: Mar 2006
Location: Iowa
Posts: 69
wow, That would be good if it were that but gosh what a large amount of time/effort to get to the bottom of it. You'll be a wizzard at helping someone else with this "someday". Shows how important the "seach" feature is on these boards.
Hurry up and check them tomorrow. Don't make us wait! LOL
gig
01-18-2009, 10:34 PM
#30
4th Gear Member
Join Date: May 2006
Location: Fort Mcmurray, Ab
Posts: 1,126
If the connector for FPDM1 keeps your car running when connected to either of the two FPDM's, it and fuel pump 1 are fine. If the connector for FPDM2 keeps your car running when connected to either of the two FPDM's, it and fuel pump 2 are fine. However, if your car stalls when connector 1 is plugged into either of the modules, with the other module unplugged, there is something wrong between connector 1 and the fuel pump 1. If your car stalls when connector 2 is plugged into either of the modules, with the other module unplugged, there is something wrong between connector 2 and the fuel pump 2.
If you car sputters when you swap connectors you probably have a voltage problem. Get a multi-meter and when the modules are plugged in, and the car is on (not running) check AT THE PUMPS for 12V. Do a little connector swapping and keep testing the voltage at each pump.
If you are getting 12V at the pumps with EVERY combination of connector swapping, and your still having fuel issues your pump is screwed. Or you have gremlins.
If you are not getting 12V at both pumps, check the connector on top of the fuel pump and do the swapping again.
Your obvious goal should be to narrow down what is happening. If you come across a problem with something, test it in other ways to narrow down EXACTLY what is it.
When I was doing my searches I came to the conclusion that FPDM 1 and 2 worked, Connector 1 worked fine and pump 1 and 2 worked. Connecter two was the culprit, but I couldn't find exactly where...
If you car sputters when you swap connectors you probably have a voltage problem. Get a multi-meter and when the modules are plugged in, and the car is on (not running) check AT THE PUMPS for 12V. Do a little connector swapping and keep testing the voltage at each pump.
If you are getting 12V at the pumps with EVERY combination of connector swapping, and your still having fuel issues your pump is screwed. Or you have gremlins.
If you are not getting 12V at both pumps, check the connector on top of the fuel pump and do the swapping again.
Your obvious goal should be to narrow down what is happening. If you come across a problem with something, test it in other ways to narrow down EXACTLY what is it.
When I was doing my searches I came to the conclusion that FPDM 1 and 2 worked, Connector 1 worked fine and pump 1 and 2 worked. Connecter two was the culprit, but I couldn't find exactly where...