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Sn95.0 Wiring Harness Help

  • Thread starter Thread starter E36x302
  • Start date Start date Dec 16, 2016
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    5.0 harness help minimal sn95
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E36x302

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Dec 16, 2016
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Dec 17, 2016
#21
  • Dec 17, 2016
  • #21
90sickfox said:
Hey man ! Nice crazy build you've got there.

First, ditch the 95 computer....its the most temperamental one to choose from they don't like modifications. The easiest computers are from 89- 93. The emissions stuff can all go. The 94-95 actually do some funky stuff with the Ignition module on the distributor, that tfi module isn't compatible with earlier computers. Pins 11, 27, 31, 32, 33, 34, 42, 48, 54, 55 and related wiring could all be deleted and the car would run decent. 27 and 33 are for EGR and I see no real reason to delete them. Without being there its hard to tell what you can delete entirely. The wires running to and from the components listed can be deleted. Pins 8 and 22 are where my knowledge stops. 8 checks for a signal from the fuel pump relay and 22 is the ground for the FP relay. I don't know if the computer needs that signal to fire the injectors in a 95.

A stand alone would be a lot easier for what you're doing....but looking at your build it doesn't seem like you're the type to take the easy way out. I use mspnp2 for my car. I have some more detailed info...I'll try and post it tomorrow.
Click to expand...



Sadly you are very right ahah, the easy way seems boring and expensive ahah

as for them being tempermental, i wouldnt know yet!

the bigger issue im having now, is now that ive unwrapped the looms, im curious to what keeps the voltage for the maf and the IAT, is it the ecu or are there a set of resistors somewhere i need to keep intact, as i havent seen any just yet
 
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E36x302

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#22
  • Dec 17, 2016
  • #22
SIDE QUESTION!!! WHICH IS FUEL INLET??? OR DOES IT MATTER

 

jozsefsz

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#23
  • Dec 17, 2016
  • #23
90sickfox said:
First, ditch the 95 computer....its the most temperamental one to choose from they don't like modifications. The easiest computers are from 89- 93.
Click to expand...
This is pretty standard advice from Fox folks, but it's not universally agreed upon nor universally applicable. If you're intending to do any substantial modification or tuning - which requires a proper tune anyways, stick with the far more powerful 95 computer. Any tuner (professional or self-taught) worth their salt can easily tune the 95 computer. If you want something that will limp-along with your mild modifications, then the A9L might be right for you, if you don't mind spending $ to downgrade.
 
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E36x302

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#24
  • Dec 17, 2016
  • #24
thank you! im going to keep the T4M0, tuning shouldnt be an issue, i didnt plan on modifying it for some time. if i do, ill be rushing to get quarterhorse haha
 
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90sickfox

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#25
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I'm a little old school when it comes to T4M0....I have very little experience with them. The factory tune in them changed to be more emissions friendly. Without big changes from stock it can perform well.

@jozsefsz You are correct on my view of the T4M0. I assumed that the OP would be upgrading a lot. When tuned correctly the stock ecu is more powerful than the latter, agreed. The A9L has more support and is easier to tune...but less powerful. Guess they're both over 20yrs old. The best would be stand alone....but I respect the OPs pockets. lol

The line on the top should be the return line...the one on the bottom should be the feed.

I'm a huge QH fan. I run standalone now but Willie Lynch is the man at Dirtydirtyracing.com...he's got anything you'd need including awesome tunes.
 

Noobz347

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#26
  • Dec 17, 2016
  • #26
What dash cluster do you intend to use?

Realistically, the car can be tuned to perfection with either EEC. The 95 EEC is faster. That aside, there may also be issues with interfacing with a gauge cluster so that both are happy.
 
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E36x302

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#27
  • Dec 17, 2016
  • #27
Awesome info guys!!!!

I'm running into a slew of problems back to back ahah

seems almost like somethings not quite right with internals :/ after sitting the better part of 6 months it almost seems like the starter is hydrolocking the engine.

the starter sounds like its full of rocks when turning over the engine, and after an almost 360* it seems to freeze and the starter binds up and just makes the typical im using a lot of power but met my match humm.

After throwing a 15/16 on the crank its a bear to turn and then frees up, for as many times as id like to manually rotate it, seems odd any insight??

Gauges

BMW Speedo
BMW Fuel
Ebay RPM Gauge
Autometer Oil Pressure
Autometer Water Temp
AEM Wideband
AEM Boost Gauge

all yet to be wired in until the it cracks to life for a split second, i have a fear ill be pulling it out to be rebuilding if i cannot address the issue with a new starter and a new set of grounds.
 
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E36x302

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#28
  • Dec 17, 2016
  • #28


Anyone hungry? Rainbow Spaghetti
 
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E36x302

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#29
  • Dec 19, 2016
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SO, anyone have any leads on the ecu power? anything aside from the Keep Alive? and is there anyway to tell if the ecu is powered up? i feel like an idiot, im fairly certain ive spun and tumbled it looking for an LED hahaha
 

jozsefsz

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Dec 20, 2016
#30
  • Dec 20, 2016
  • #30
The fuel pump priming is really the only tell, other than getting out a voltmeter and looking for signs of life. You could always run a KOEO test too -- watch out for the fan if you do that.
 

Noobz347

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#31
  • Dec 20, 2016
  • #31
E36x302 said:
SO, anyone have any leads on the ecu power? anything aside from the Keep Alive? and is there anyway to tell if the ecu is powered up? i feel like an idiot, im fairly certain ive spun and tumbled it looking for an LED hahaha
Click to expand...


There's no LED.

96 Explorer 5.0




 
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E36x302

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#32
  • Dec 21, 2016
  • #32
AWESOME! much easier than the one i was struggling to read ahhaah

any idea what all needs 12v aside from keep alive? since im not running the CCRM?
 

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#33
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The following are diagrams courtesy of Tmoss & Stang&2birds

94-95 5.0 Mustang ECC




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.



TFI module wiring for 94-95 Mustang GT
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-IgnitionControlModule.gif

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

O2 sensor wiring harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangO2Harness.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

Mustang 5.0 Lights and Radio schematic, by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxLights-Radio_diag.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

T5 Cutaway showing T5 internal parts
http://www.veryuseful.com/mustang/tech/engine/images/5_Speed_Cutaway_Illustrated.jpg

Visual comparison of the Ford Fuel Injectors, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/Ford_Injector_Guide.jpg

Convertible top motor wiring http://www.veryuseful.com/mustang/tech/engine/images/mustang88VertTopMotorCkt.gif

Engine mounted fuel injector harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangEngineHarness.gif

Location of the TPS, IAB, and the 10-pin connectors on a 5.0, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/TPS_IAB_Pic.jpg

Starter circuit
http://forums.stangnet.com/attachment.php?attachmentid=21328&d=1080916057

Alternator diagram for 94-95 Mustangs.
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-Alt.gif
 
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