Startup = Moment of truth = FAIL - 5.0 EFI conversion help

68converted · May 30, 2008

After a ton of help from you guys and some major setbacks, I went to start her up and there is no power to the EFI pump. I am told that when the key is on there should be a 5 second cycling of the pump then it should shut off. I metered the terminals just as the key was turned on and there is no power.

I wonder if the computer has power? or the fuel pump relay? How do I check? I would assume the first step is to get a reading at the relay, if that is a no go, then how do I check for power at the computer?

All the old wiring/devices/lights work, the dash lights work, fuel sender is reading, I am getting spark to the spark plugs, and the engine turns over without a problem...

bnickel · May 30, 2008

i would first start by checking that relay and if that passes then i'd look for a wiring diagram to see if you have that circuit setup correctly and THEN check the computer out

67coupe · May 30, 2008

Fox's had an inertia switch to cut off fuel delivery after an accident. I wonder if this circuit is currently open.

Run through this list and see if what you find.

http://forums.stangnet.com/showpost.php?p=6161267

Also, jump over to 5.0 tech and search. Lots of info there. Good luck.

68converted · May 30, 2008

bnickle- Ok, here is what I found. I have a wire from the fuel pump pin on the ECC to the Fuel Pump relay, to the inertia switch, to the fuel pump.

But the huge ford wiring diagram shows the wires should run from the ECC to the inertia switch, to the fuel pump relay, and back to the pump.

My routing is far less wire and accomplished the same thing??? I think?

67coupe- Thanks for that link. I will go through the checklist tonight.

I will post some more info tonight. Thanks for the help.

yeloxr7 · May 30, 2008

Are you getting power to the ECU? Are the grounds for the relays and ECU secured properly? Is the plastic guard for the big plug on the ECU in place and pressing the wires onto the ECU pins?

BarnStang · May 30, 2008

http://www.veryuseful.com/mustang/tech/engine/
One of the best EFI resources.

Stanger007 · May 31, 2008

The fuel pump can also be cut "on/off" at the test port as a quick test.

Otherwise I'd start from pin 22 and follow the power to the relay and then down to the pump.

Good luck!

Wes

68converted · May 31, 2008

I just started unwinding the harness and I don't think that I even have the fuel pump relay powered from pin 22? I almost have the whole thing pulled apart, so I will have the answer in the morning.

68converted · Jun 1, 2008

Crap,
I have discovered that the bastards from Colorado Mustang Specialists sold me a harness out of a Thunderbird or something else?? (I hope the moter and computer were from a Mustang- I'll find out tomorrow) This stuff is hard enough without trying to discover how any of this works when the majority of the wires don't match anything from the big schematics sheets for the Mustang. The Fuel Pump circuit/relay, and now I find a bunch of other stuff, are all the wrong colored wires.

First it was the wrong accessory brackets, and not the harness... I am so sick and tired of those crooks I am going to flat out sue the jerks.

So now I have to go out and find a harness from a Mustang. Man, nothing is going right with this project. Any suggestions?

I am so pissed.

68converted · Jun 2, 2008

Alright, I have calmed down. I am determined to get this finished.

Here is what I have: Blue/orange wire from pin 22 running out to the EEC test port, and back to a grey plug under the dash that carries the fog lights wiring (4 wires), a Tan/Yellow wire which runs back to the Fuel pump relay, and a red wire which joins a group/splice of about 5 red wires in the harness (this group includes the red wires from the ECU Relay- which do not have power with key on)

On the Fuel pump relay, I have the following wires: Red - 30 (runs back to the harness splice with the other red wires, Black/orange to 85, the tan/yellow wire from plug above to 87 and tan or grey/lt blue at 87a.

When the key is turned on (not start) I should have power to 30 but I don't. Can I just run a wire from 30 straight to the (+) on the Solenoid? Is there anything in the fuel pump relay circuit that is going to cause me issues, if I just isolate it, using the wire from pin 22 to switch the relay?

I just don't have any more money to spend to bring it to someone. Is there a wiring guru that can help me out? Thanks.

CochinoFilipino · Jun 2, 2008

Edit: ignore me

CochinoFilipino · Jun 2, 2008

My diagram doesn't show colors. But if I'm understanding it correctly, your fuel pump relay should have:
pin 1- Constant power from the battery (also goes to pin 1)
pin 19- FPM fuel pump monitor
Fuel Pump
pins 37/57 -vehicle power
pin 22 -control circuit (controls the fuel pump relay by providing ground, also runs to self test connector)

68converted · Jun 2, 2008

CochinoFilipino said:
My diagram doesn't show colors. But if I'm understanding it correctly, your fuel pump relay should have:
pin 1- Constant power from the battery (also goes to pin 1)
pin 19- FPM fuel pump monitor
Fuel Pump
pins 37/57 -vehicle power
pin 22 -control circuit (controls the fuel pump relay by providing ground, also runs to self test connector)

Thanks man, I don't have my diagrams with me, they are with the car. But I am heading over there now.

Hey I owe you some pics of the exhaust as well, but I have to get this figured out first. I'll take the pics tonight and hopefully post them.

BarnStang · Jun 2, 2008

You can't go at the EFI problems in the traditional manner. Cochino has you on the right track. THe computer supplies a ground to key the relay. I'll pull up my EFI stuff and see if I can help. But like you said, if it's a THunerbird harness, it may not match anything I have. First, what is the computer code you have? The common ECCs are the A9L (5 speed) and the A9P (auto)

22 - Tan w/lite green strip
37/57 - Red

These are frm a 87-91 Mustang diagram

I can't find a picture of the fuel pump relay so I can't correlate the relay pin numbers to the wires...but when the key comes on (run) the ECC pwr relay should close, and 12v goes through the enertia switch to the fuel pump relay. THe ECC should then ground pin 22 and close the fuel pump relay. You need to know that the ECC pwr relay s closing and sending 12v out first. Cause it sounds like you are either not getting 12v to the fuel pump relay or you are not getting the ground from the ECC to key the fuel pump relay. If the ECC pwr relay is not closing then you are not getting 12v to the fuelpump relay, AND since the ECC is not powered up, you are not getting the groundto the other side of the coil in the fuel pump relay.

CochinoFilipino · Jun 2, 2008

Don't sweat the pics. Concentrate on getting your car running. I'll PM you my email address if you want the diagrams I have. I can scan T-bird diagrams too.

68converted · Jun 2, 2008

BarnStang said:
You can't go at the EFI problems in the traditional manner. Cochino has you on the right track. THe computer supplies a ground to key the relay. I'll pull up my EFI stuff and see if I can help. But like you said, if it's a THunerbird harness, it may not match anything I have. First, what is the computer code you have? The common ECCs are the A9L (5 speed) and the A9P (auto)

22 - Tan w/lite green strip
37/57 - Red

These are frm a 87-91 Mustang diagram

I can't find a picture of the fuel pump relay so I can't correlate the relay pin numbers to the wires...but when the key comes on (run) the ECC pwr relay should close, and 12v goes through the enertia switch to the fuel pump relay. THe ECC should then ground pin 22 and close the fuel pump relay. You need to know that the ECC pwr relay s closing and sending 12v out first. Cause it sounds like you are either not getting 12v to the fuel pump relay or you are not getting the ground from the ECC to key the fuel pump relay. If the ECC pwr relay is not closing then you are not getting 12v to the fuelpump relay, AND since the ECC is not powered up, you are not getting the groundto the other side of the coil in the fuel pump relay.

The computer is a A9P and by the bar code, the Dealership looked it up and it is indeed from a 91 Mustang. Aren't all the harnesses from 89-93 the same Auto for Auto? I can't imagine Ford would change the wiring patterns year over year; maybe I just trust in the Blue Oval too much.

I will check the items you listed and get back to you. I am at the garage now, so give me a few. Being color blind make this a long process with my 9 year old helping me to identify the colors. Kind of cool to get him involved though, it is his car!!!

68converted · Jun 3, 2008

Who knows what harness I have but a friend was over and helped me trace a bunch of wires and a lot do not match.

It is just too much to try and mess with; I am going to have to find a harness somewhere. Most I have seen are being sold with a computer for big bucks. Any ideas?

CochinoFilipino · Jun 3, 2008

There's afew on ebay for $135. But they don't include the injector or o2 sensor harnesses. You could probably use the injector harness you have., but make sure the firing order is right. I don't think T-birds were H.O.

68keyblr · Jun 3, 2008

check out www.fordfuelinjection.com

Great site where you can get all of the pigtails and harnesses you need, as well as diagrams and schematics.

Also, use that checklikst that was posted by 67coupe - I used it to get my '88 GT running. JRichker is a guru over on the 5.0 forum, and he's the guy that put that list together.

Stanger007 · Jun 4, 2008

I watched eBay and Corral to find mine.

Startup = Moment of truth = FAIL - 5.0 EFI conversion help

68converted

Member

bnickel

67coupe

68converted

Member

yeloxr7

Member

BarnStang

Stanger007

68converted

Member

68converted

Member

68converted

Member

CochinoFilipino

CochinoFilipino

68converted

Member

BarnStang

CochinoFilipino

68converted

Member

68converted

Member

CochinoFilipino

68keyblr

Stanger007

Similar threads

Startup = Moment of truth = FAIL - 5.0 EFI conversion help

Member

Member

Member

Member

Member

Member

Member

Member

Member

Similar threads

Privacy & Transparency

Privacy & Transparency