ECC relay out
 

we finally got the ECC relay out, out the OHM meter on it, and nothing.....
original fuel pump relay gets .62, seems decent
new fuel pump relay only gets intermittent readings
and ECC relay doesnt get any SO....

We will have to try a new ECC relay now and see if that does it.
Will also pick up a new fuel pump relay just in case, since the old one works, but could still be part of the problem.

I'll keep you posted:)

EEC Relay
 

We are going now to pick up that new EEC relay and new fuel pump relay now and see how that works. Then we will come back to research the wiring diagram if that doesnt work.

Weird thing was the EEC relay available at ALL the parts stores is a 5 pin, the port had allowed for 5 pins too, but the relay we took out was only 4 pins. Don't think it will hurt anything to put a 5 pin in there since it appears there is a spot for it anyhow. Just cant figure out why the ECC relay that was in there was only 4. Weird Does anyone know what the difference this would make? It is the same parts number. No one has a 4 pin.

Anyway, We will keep you posted.

Happy Memorial Day!

Giving up
 

It didn't work....We have decided that this is way too much for us to handle. We have to tow it to a shop...

Thanks for your help.

I don't want to step on any toes here but I still have a hankering that it is the pump. You replaced the regulator and still had nothing. The fuel pump keeps running because it can't build up enough pressure. Try the starting fluid again. If it hits just a little lick, then you have no problems except for fuel delivery. Don't go crazy with the ether either. It is not good for cars. I assume you already know this, but you need to spray ether while someone else is cranking.

Car is fixed:)
 

HI all-

Just wanted to update you, Car is back from the shop. It was the computer itself. They couldnt even pull codes from it. I am hoping someone else having similiar problems can read this and cut to the chase, so to speak. For good measure mechanic adjusted timing too.

The computer itself is a FORD only part, so with labor it was a spendy fix. I guess we had hoped that it would have been something simple that we could fix to save $$$. Overall we did replace about $100 worth of parts and spent money twice on towing, once to bring her home for us, and once to the shop when we gave up. So, My advice to others would be, if you have checked the inexpensive parts, don't waste any more time or money, get it to someone who can pull those codes, its worth it.

Thanks again to all of you for your help! I hope now we can fix her up to look as pretty as she sounds:)

Mustanglover71

ahh as I thought. Sounded like the EEC from the beginning.

glad to hear that you are back on the road. did the mech say what may have caused the cpu to go bad?

Re: Help! Mustang wont start!
 

Same problem with 1990 LX 5.0:

I recently acquired this car from a friend. It has set-up for 3 years in his garage. He told me that the last time it was running it ran really rough and he could smell fuel in the exhaust like it was running really rich. When he towed the car to my house, it did not have a battery. Once a new battery was in and the ignition was turned to the on position, fuel sprayed out the rear end of the car.

After investigation it was found that the fuel line that runs from the pump to the filter was laying directly on the replacement exhaust that he had put on the car 1000 miles before he stopped driving it. The fuel hose had a hole burned in the side of it. After telling him, he said he would never visit Midas again!

Once a new hose was found I installed it and attempted to start the car. Same thing as Mustang Lover's problem: engine cranks well, but never turns over; fuel pump continues to run and never shuts off as normal after pressure build-up; pulled plugs and found good spark on several; we can hear a gushing sound in the fuel rail near the regulator (almost sounds like an air leak); pushed in shrader valve on fuel supply and fuel gushes out with what seems to be good pressure (have not verified with gauge); engine tries to turn over and run with starter fluid sprayed into intake.

It seems we have the identical problem with different operating conditions. Mustang Lover was driving as normal and my car has been sitting idle for 3 years. I did pull the tank down to change the fuel hose and did not notice before, but now the fuel guage does not read any level. I know it has at least 5 gallons in the tank.

Based on the previous posts, it seems as if I am going to purchase a computer also, but I don't really want to take it to a shop. The local ford dealer lists the computer for $253.00 remanufactured, which was better than I thought it would be.

Let me know what y'all think please.

-Scott

Re: Help! Mustang wont start!
 

try checking the fuel pump relay, i had the same problem

Re: Help! Mustang wont start!
 

try checking the fuel pump relay

Re: Help! Mustang wont start!
 

I will change it out (fuel pump relay)....But would this keep the engine from starting?

Thanks

Re: Help! Mustang wont start!
 

Hi just went through same problem it was computer could'nt pull any codes,all the electronics and wiring were getting 12 volts but eec wasn't sending out the the negative for all the components,talk about pain in the ass. Good to see you got it fixed,eec remanufactured was 140.00 canadian.

Re: Help! Mustang wont start!
 

it sounds like the injectors might be clogged, you said that you have pressure to the rails and you definitly have spark right? And when you sprayed starting fluid in the motor it fired and the stopped, it could be that the injectors have some debris in them, and its preventing enough fuel to get into the cylinder.

Re: Help! Mustang wont start!
 

You could also try replacing the coolant temperature sensor that tells the computer if the engine is cold or warm. The sensor is located on the passenger side of the intake by the thermostat. Last summer I had mine disconnected when I took out the coolant hardline and the car ran fine and then didn't start. Had to actually start the car like it was flooded and carburated by holding the pedal to the floor. Just a suggestion, hope you get the problem fixed.