Here we go again!
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Here we go again!
I have been chasing an intermittent miss for about 1-1/2 yrs.
It is like the key gets turned off for a second. I have replaced everything in the ignition system & various sensors. I recently replaced ECU w/ a reman unit. Symtpons a little better but still not right. I drove it for a few miles, now I'm getting a CE light, which I never got w/ old ECU. Code is ACT voltage too high. I really could use some help!
It is like the key gets turned off for a second. I have replaced everything in the ignition system & various sensors. I recently replaced ECU w/ a reman unit. Symtpons a little better but still not right. I drove it for a few miles, now I'm getting a CE light, which I never got w/ old ECU. Code is ACT voltage too high. I really could use some help!
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From: Easton,Ks
It is not likely a ECU as you call it can cause a intermittent miss.
It does sound like you traded a good ECU (EEC/PCM) for a bad one. I am not a fan of a reman unit. It seems like most on here that use them come back very soon with problems. If you remember your old program code off the old one see if you can find one at a salvage yard or on ebay. If you still have the old one put it back in and we can try to help you fix your problem.
If you do not have the code try and find one out of a truck just like yours, same engine, transmission, year and so on. Check the truck for the same calibration code on the door as yours then you know you are getting the right one and I can also post the Ford part number if you give us your calibration code.
It does sound like you traded a good ECU (EEC/PCM) for a bad one. I am not a fan of a reman unit. It seems like most on here that use them come back very soon with problems. If you remember your old program code off the old one see if you can find one at a salvage yard or on ebay. If you still have the old one put it back in and we can try to help you fix your problem.
If you do not have the code try and find one out of a truck just like yours, same engine, transmission, year and so on. Check the truck for the same calibration code on the door as yours then you know you are getting the right one and I can also post the Ford part number if you give us your calibration code.
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I should have said that the one in the truck was a reman unit as well. The original computer was causing an intermittant miss, although different than this one. The original ECU was replaced approx 3 yrs ago.
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From: Easton,Ks
Why do you think an ECU can cause an intermittent miss?
Did you replace the original ECU for this intermittent miss?
The only way an ECU could cause an intermittent miss is if it did not fire the bank of injectors.
I do not think an ECU could do this intermittently.
Sounds like you have a wiring problem.
Did you replace the original ECU for this intermittent miss?
The only way an ECU could cause an intermittent miss is if it did not fire the bank of injectors.
I do not think an ECU could do this intermittently.
Sounds like you have a wiring problem.
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Why do you think an ECU can cause an intermittent miss?
Did you replace the original ECU for this intermittent miss?
The only way an ECU could cause an intermittent miss is if it did not fire the bank of injectors.
I do not think an ECU could do this intermittently.
Sounds like you have a wiring problem.
Did you replace the original ECU for this intermittent miss?
The only way an ECU could cause an intermittent miss is if it did not fire the bank of injectors.
I do not think an ECU could do this intermittently.
Sounds like you have a wiring problem.
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From: Easton,Ks
The computer has very little to do with the Ignition systems operation. The only thing it does with the Ignition System is adjust timing advance (and only then with the SPOUT in) other than that it just monitors the Ignition System.
The Ignition system is operated mainly by the ICM (or TIF) module.
If you pull out the SPOUT you completely disconnect the Ignition system from the ECU. If it still misses it can not be the ECU unless it does not ground the fuel injector bank. That would not be likely unless the wiring or plugs are bad from the injectors to the ECU.
The Ignition system is operated mainly by the ICM (or TIF) module.
If you pull out the SPOUT you completely disconnect the Ignition system from the ECU. If it still misses it can not be the ECU unless it does not ground the fuel injector bank. That would not be likely unless the wiring or plugs are bad from the injectors to the ECU.
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Fleet Owner
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From: Easton,Ks
That sounds more like bad spark plugs, what brand are you using?
Have you set the Ignition timing with timing light with the SPOUT out?
Have you set the Ignition timing with timing light with the SPOUT out?
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The miss under load was cured by changing computers 3yrs ago. This miss is different, it feels like the key gets turned off then back on. I have changed plugs several times, as well as, wires, cap, rotor, dist, module, ign switch & the wires are routed per TSB. I'm at a loss. It also stalls occasionally & gets 12-13mpg hwy, less than 10 towing bass boat. Help!
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From: Easton,Ks
Fixing it by c/o the ECU leads me to think if you unplugged it and plugged back in it would have done the same thing. I would look at the ECU plug and the wires going into the plug.
With all of that c/o it only leaves the wiring harness and it's plugs.
I take it you are using Motorcraft spark plugs.
It sounds like you may need to put a Recorder on it and when it does it you can play it back and see what stopped working. Of course the Recorder has to be plugged into the Monitor.
Any of the shops around you have the Monitor & the Recorder for the EEC-IV system.
With all of that c/o it only leaves the wiring harness and it's plugs.
I take it you are using Motorcraft spark plugs.
It sounds like you may need to put a Recorder on it and when it does it you can play it back and see what stopped working. Of course the Recorder has to be plugged into the Monitor.
Any of the shops around you have the Monitor & the Recorder for the EEC-IV system.
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I'm using Autolite #25 plugs. What am I looking for in the ECU plug? Do I tug on each wire to see if its loose? Do I check every sensor connection? How much is it to have someone put the recorder & monitor on it? Thanks for your help!!
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From: Easton,Ks
That or try to twist them by hand and see if the wire moves and the pin does not.
Most of the sensors would not cause it to cutout.
All Ford dealerships had these at one time but a lot of them have unloaded the EEC-IV testing boxes. They seem to think EEC-IV is old and dead and no longer need to be serviced. Most of their staff in the service bays are up to date on the newer stuff but do not seem to know much about anything older than OBDII.
Some service centers may have picked up some of the test boxes as I have. I have a complete set of the EEC-IV test boxes.
The EEC-IV test boxes used to be part of the testing they did when they ran in to something that they could not get a handle on. I could not guess what they would charge you if you find someplace that still has the Monitor & Recorder.
Post Fiend
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From: Bonita Springs FL
Thanks
