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Fuel Pump

  • Thread starter Thread starter B-radster
  • Start date Start date May 28, 2014
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B-radster

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Apr 22, 2014
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May 28, 2014
#1
  • May 28, 2014
  • #1
Getting ready to buy my 3rd fuel pump............ Not sure Why? Ive checked every inch of wiring for frays, nicks, scratches, corrosion, looseness....relay wires are good, fuse wires are secure, fuse is good. no corrosion in any of the connectors all pins and recievers appear good with a snug fit. Stock fuel pump went out within 20 minutes of run time after engine rebuild. 100k miles so not to odd really but Cheap ass ebay(i know, i know) 255lph High flow pump burnt up after about a hr and a half. Im leaning towards i just got what i paid for with the ebay p.o.s. SO.....
What is a good Brand and flow rate for a 5.0 rebuilt and bored, headwork, 70mm tb and ported gt40 manifolds and heads, BBK MAF with 24lb injectors? Do you really need a high flow pump? Without a massive build i cant see needing 50gph??????
 

B-radster

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Apr 22, 2014
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Grass Lake, Michigan
May 28, 2014
#2
  • May 28, 2014
  • #2
Alrighty. Scratch the above nonsense. Got in today. Turned key and fuel pump turned on. Investigation turn up partially stripped TPS allowing voltage to drop from .971 to .233. Got another installed reset to .971 and after about a hr it stalled flat popped up TPS and looks like this.... Did i screw up? Seems only 1 friggen way to put it on. Or is this another specialty item i need from building the engine?
 

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B-radster

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May 29, 2014
#3
  • May 29, 2014
  • #3
no one?
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
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May 29, 2014
#4
  • May 29, 2014
  • #4
Wtf did you do to that thing? Buy a replacement. Do not cut it, do not try abd adjust it. Ford tos is NON adjustable.
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
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#5
  • May 29, 2014
  • #5
Tps. Stupid smartphone
 

B-radster

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May 29, 2014
#6
  • May 29, 2014
  • #6
had to elongate the holes to adjust voltage. When putiing on TPS voltage is .288 wont turn on pump. the center is what concerns me. why would it eat off a flat? the butterfly tension is not that great.
 

B-radster

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Apr 22, 2014
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May 29, 2014
#7
  • May 29, 2014
  • #7
I have a new BBK throttle body and TPS to put on that has a adjustment bushing so you dont have to elongate the holes.
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
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May 29, 2014
#8
  • May 29, 2014
  • #8
Fwiw the car will run in limp mode with the Tps disconnected. You have bigger problems. As suggested put on a new one and do not adjust it. If it's out of range it's bad. End of story.
 

B-radster

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May 29, 2014
#9
  • May 29, 2014
  • #9
Why are there so many posts on so many sites including this one about proper TPS range if there is no adjustment?
 

B-radster

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Apr 22, 2014
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Grass Lake, Michigan
May 29, 2014
#10
  • May 29, 2014
  • #10
And what is fwiw??
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
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gainesville
May 29, 2014
#11
  • May 29, 2014
  • #11
Fwiw for what it's worth. Urban legend just like your distributor being a tooth off. Ford did not build Tps adjustability into the eec programming. Replace that unit and dump codes. Don't do a single other thing until you do that unless you like wasting money and chasing your tail. The computer will tell you exactly what is wrong with your car. Start there.
 
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B-radster

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May 29, 2014
#12
  • May 29, 2014
  • #12
Dumping codes is a issue because previous owner for some reason rewired EEC plug and i can not find the proper wires where i am comfortable jumping it. I have 2 tan/green wires tied together in slot 1, a tan/red in slot 2, a tan in slot 3 and a gray/red in slot 4. No single pin connector either.......
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
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May 29, 2014
#13
  • May 29, 2014
  • #13
Might be better off using a new harness.
 
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jrichker

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  • May 29, 2014
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Clean the gray/red wire off with some solvent. If it comes up as white/red after the cleanup, jumper it to the black/white ground or to battery ground. The codes should dump.

Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.





If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10




Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see www.midwayautosupply.com/Equus-Digital-Ford-Code-Reader/dp/B000EW0KHW Equus - Digital Ford Code Reader (3145It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.




TPS troubleshooting

Setting the TPS at .98 or .99 volt is a Bozo Internet Myth. When the computer powers up and initializes the TPS sensor, whatever it reads is the zero starting point for it. In other words your .98 volt becomes 0 volts and the computer watches for increases in voltage from that point upward.


Setting the TPS: you'll need a good Digital Voltmeter (DVM) to do the job. Set the TPS voltage at .5- 1.1 range. Because of the variables involved with the tolerances of both computer and DVM, I would shoot for somewhere between .6 and 1.0 volts. Unless you have a Fluke or other high grade DVM, the second digit past the decimal point on cheap DVM’s is probably fantasy. Since the computer zeros out the TPS voltage every time it powers up, playing with the settings isn't an effective aid to performance or drivability. The main purpose of checking the TPS is to make sure it isn't way out of range and causing problems.


Wire colors & functions:
Orange/white = 5 volt VREF from the computer
Dark Green/lt green = TPS output to computer
Black/white = Signal ground from computer

TPS troubleshooting steps:
1.) Use the Orange/white & Black white wires to verify the TPS has the correct 5 volts source from the computer.
2.) Use the Dark Green/lt green & Black/white wires to set the TPS base voltage. Try this... All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a voltmeter with a 1 or 3 volt low scale to do the job.

The Orange/White wire is the VREF 5 volts from the computer. You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS. Use a pair of safety pins to probe the TPS connector from the rear of the connector. You may find it a little difficult to make a good connection, but keep trying. Put the safety pins in the Dark Green/Lt green wire and Black/White wire. Make sure the ignition switch is in the Run position but the engine isn't running. Set the voltmeter on the 2 volt range if it doesn’t auto range.

Here’s a TPS tip I got from NoGo50

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks.

(copied from MustangMax, Glendale AZ)

A.) Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

B.) When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

C.) Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

D.) The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.

The TPS is a variable resistor, must like the volume control knob on a cheap radio. We have all heard them crackle and pop when the volume is adjusted. The TPS sensor has the same problem: wear on the resistor element makes places that create electrical noise. This electrical noise confuses the computer, because it expects to see a smooth increase or decrease as the throttle is opened or closed.

TPS testing: most of the time a failed TPS will set code 23 or 63, but not always. Use either an analog meter or a DVM with an analog bar graph and connect the leads as instructed above. Turn the ignition switch to the Run position, but do not start the engine. Note the voltage with the throttle closed. Slowly open the throttle and watch the voltage increase smoothly, slowly close the throttle and watch the voltage decrease smoothly. If the voltage jumps around and isn’t smooth, the TPS has some worn places in the resistor element. When the throttle is closed, make sure that the voltage is the same as what it was when you started. If it varies more than 10%, the TPS is suspect of being worn in the idle range of its travel.

TPS will not go below 1 volt
Engine mounted sensor circuit: Check the resistance between the black/white wire on the TPS and battery ground. It should be less than 0.5 Ohms. Higher resistance than 0.5 ohms indicates a problem with the 10 pin connector, computer or the splice inside the main harness where the wire from the 10 pin connectors joins the rest of the black/white wire.



See the graphic for the location of the 10 pin connectors:
Diagram courtesy of Tmoss & Stang&2birds



See the graphic for the 10 pin connector circuit layout.


Unplug the white 10 pin connector to do some resistance testing. It is good time to clean the connector pins and examine the connector for corrosion, broken wire or other damage. See http://oldfuelinjection.com/?p=85 for help in this department.

If the resistance on the TPS Black/White wire and pin 1 of the white engine fuel injector harness 10 pin connector, is more than 0.3 ohm, you have bad connection or broken wiring. Repeat the test using the pin 1 of the white body side 10 pin connector and battery ground. You should have less that 0.5 ohm. More than that is a damaged signal ground inside the computer or bad connections or wiring.
 
Last edited: May 29, 2014

B-radster

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Apr 22, 2014
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May 29, 2014
#15
  • May 29, 2014
  • #15
I cleaned them and would still call it gray/red. So would wife. Here is a pic with wires out of connector.
 

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B-radster

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May 29, 2014
#16
  • May 29, 2014
  • #16
These 2 connectors running off main loom have a white/red unbroken wire but no other white/red or black/red nearby? LOL
 

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B-radster

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May 29, 2014
#17
  • May 29, 2014
  • #17
Found the STI connector gray plug under the booster but still no white/red wire.
 

90lxwhite

I'm kind of a She-Man
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May 30, 2014
#18
  • May 30, 2014
  • #18
Fwiw
 
Last edited: May 30, 2014

jrichker

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#19
  • May 30, 2014
  • #19
B-radster said:
I cleaned them and would still call it gray/red. So would wife. Here is a pic with wires out of connector.
Click to expand...

The gray connector shown in the other picture isn't for the computer test point.

Peel the covering off the harness a little bit and I bet you'll find the gray/red wire is a white/red wire. If so, then ground it to a black/white wire or to the battery negative post.

Still not sure? Remove the passenger side kick panel and disconnect the computer connector. There is a 10 MM bolt that holds it in place. Look for pin 48 on the diagrams below. Measure the resistance on pin 48 of the computer wiring harness connector to the gray/red or white red wire: it should be less than 1 ohm. If it isn't, then you have the wrong wire.




Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif


Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif
 

B-radster

Member
Apr 22, 2014
80
0
7
Grass Lake, Michigan
May 30, 2014
#20
  • May 30, 2014
  • #20
jrichker said:
The gray connector shown in the other picture isn't for the computer test point.

Peel the covering off the harness a little bit and I bet you'll find the gray/red wire is a white/red wire. If so, then ground it to a black/white wire or to the battery negative post.

Still not sure? Remove the passenger side kick panel and disconnect the computer connector. There is a 10 MM bolt that holds it in place. Look for pin 48 on the diagrams below. Measure the resistance on pin 48 of the computer wiring harness connector to the gray/red or white red wire: it should be less than 1 ohm. If it isn't, then you have the wrong wire.




Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif


Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif
Click to expand...


I wish it was but it was not. i peeled back the harnesses to center of the firewall and it was clean and gray/red also peeled covering back to the coil and to the firewall. no white/red wire to be found......
 
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