Ford EEC-IV guru's check in here!

[mustang501993]

Has anyone ever had these symptoms:

1. Car cranks and fires but the second you let go of the key it quits.

2. Every once and a while it will run for 3 or 4 seconds.

3. Fuel is OK, pump and pressure.

4. Coil is good.

5. Every single wire in the system has been metered and is OK

6. Car will continue to run and respond to throttle changes with the key in the "Start" position (i know this is bad for the starter).

7. TFI module was tested and found to be good.

8. Ignition switch was replaced and is good, along with the acuator rod or whatever you call it.

This is killin me, has this ever happened to anyone here? The only thing I can think of is the ECM, but why would it start at all? If there is anyone from here that is a Ford mechanic that knows the ins and outs of the EEC-IV it would be greatly appreciated if you could help. ANy ways a home mechanic could test it would be great. The computer is an A9L. Also, the motor and computer are not original and before I go and order a computer from the store I was wondering if anyone knew what the A9L originally came in. They have no way of cross referencing this at the store.
Thanks

 

[HISSIN50]

per your request, i am not qualified to reply, but i will.

i would be chasing wires (again, i know) rather than the puter. have you gone through the ignition switch itself (the recall item) and made sure no wires are shorted out or miswired? it sounds like a wire that should be key-on hot is tied into the starter interlock circuit.

good luck.

 

[mustang501993]

I have the old ignition switch and the new one and they both do exactly the same thing. The car ran 2 weeks before this and it sits in a garage the rest of the time.

 

[Notchbck93]

As a fellow reef blue notchback owner here is what I suggest you think about:

So, your ig switches seem to be fine, then why is it when you let go of the start position the car stops?

When you have the key in the on pos I assume that there is power to the coil, which means there should be power to the coil with the key in the run position after you let go of the ig switch, after starting your ride.

If your power side is fine, then it's time to check good ol ground on the coil. Computer controls that as well, and that is what controls coil saturation time.


Look at the ig switch schematic in a haynes manual and see what should have power when. Ohming wires is a great start, but checking voltage drop is another along with power and the proper time.

I don't believe that the A9L is at fault, I believe that you have other electrical issues.

 

[HISSIN50]

i will note for future searchers of this thread, as it is a source of misunderstanding, that the ignition switch refers to the electrical connector. it is often confused with the ignition lock cylinder, which is the mechanical lock the key inserts into. again, not directed at anyone in this thread, but info for others.

 

[Notchbck93]

i will note for future searchers of this thread, as it is a source of misunderstanding, that the ignition switch refers to the electrical connector. it is often confused with the ignition lock cylinder, which is the mechanical lock the key inserts into. again, not directed at anyone in this thread, but info for others.

Great Point!

 

[ripperdog]

The A9L computer was used in 89-92 manual transmission cars.

As far as your starting problems, we really need to know a little more about exactly what work you have done on the car. Was it originally EFI or have you installed all the wiring your self while doing a conversion? If so, you may have gotten some of the 12 volt start/run wiring mixed-up. Was the original combination a manual or automatic? If you use a manual trans computer in combination with an O2 sensor harness from an automatic trans car, you can do damage to the computer due to different wiring schemes.

 

[89roadster]

Not sure this solves or helps, but after months and months of chasing down codes 84, 44, and 94 replacing several parts, I decided to take a look at the computer. I tore it apart and found that a couple traces on the board had burned out and one of the transistors was dead - a rebuilt ecc is on the way from Autozone now (repaired the traces and transistor, but don't really trust them).

Maybe grab a computer from a friends car and try it out.

 

[rd]

You may have done all this, but my suggestion is check:

The ignition switch run position power wire to the coil. It should be a resistor wire, so that the coil only gets 9 volts in the run position. It sounds like you get power to the coil (or module) in start, but not in run. The two most common causes are a failed run power wire, or the ignition switch is not properly adjusted. The switch is slotted and must be adjusted up or down the column, so that it make contact in each position of the acutation rod. My Bronco with a tilt wheel was real sensitive to this issue.

I would check and examine the coil run power wiring closely, electrically and visually. With the car not running, and the key on, do you have power to the coil and the ignition. Visually look for a wire that has perhaps broken all but one or two strands at a connector, as it will carry enought power to run the car for a second or two, but will overheat immediately and fail. Been there, done this one also.

Next up is the TFI or the pickup in the dist. These can work for short periods and fail when they warm up. Duraspark distributor pickup coils have some history of doing this, for example.

 

[mustang501993]

When I say ignition switch, I am talking about the electrical connector. When I mentioned the "rod" I was talking about the rod that goes into the switch to move the slider thing in the electrical switch. There is power to the coil in both the start and run positions. I have a buddy with an extra computer that was out of an 88 that had a mass air conversion but it doesn't have the three digit computer name on it. Will any computer from a 5 speed start and run my car? The ignition system is completely stock on my car, save for the cap, rotor and wires. The car is a 93 and the motor and trans is an 89, I believe it was a theft recovery, I am not sure if the harness is from the 89 or if it is original. Let me say this though, I have had the car for 8 years and put about 30,000 miles on it since I bought it and it has never had a starting or running problem. I don't think that I have a mismatch of parts.

 

[mustang501993]

As far as adjusting the ignition switch, I cant remember if both of the holes are slotted in it to allow adjustment. Is it correct to assume that switch is operating correctly if when the key is turned to the run position the fuel pump turns on? Also, for the TFI module, I had it tested at autozone, it checked out OK. Plus, with the key in the run position, when you move the distributor back and forth past a pickup point, the fuel pump cycles, would this not indicated that is working?

 

[mustang501993]

As a side note, I am getting power to the coil in both the start and run position.

 

[mustang501993]

Just wanted to let you guys know that it was the TFI module! I took that thing to 2 different autozones and they both said it was fine. I borrowed one from one of my buddies and put it in and the car fired right up! Thanks for all of your help!

 

[Notchbck93]

Glad to hear you have your 93 back on the road! Thanks for the update!

 

[rd]

Another thanks for the info on what fixed it!

 

[Scones]

Damn those TFI's...one had me stumped for ages lol