'88 f350 gas injectors not working
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'88 f350 gas injectors not working
One day my truck just quit running, for no apparent reason. Fuel pump cycles at turn of key, It has spark, it has 45 psi at fuel valve on rail. Noid light on injector plug is dark upon engine cranking. I replaced the EEC and still no good. Should I replace the distributor? 
Please help
Please help
Fleet Owner
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From: Easton,Ks
You need to get the NOID light flashing first before worrying about spark.
With a test light check to see if you have power on the red wire at one of the injectors with the key on.
If you do have power more than likely you are not getting a PIP from the distributor.
Replace the distributor.
You will not have spark without a PIP also.
With a test light check to see if you have power on the red wire at one of the injectors with the key on.
If you do have power more than likely you are not getting a PIP from the distributor.
Replace the distributor.
You will not have spark without a PIP also.
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injectors still not working
well I replaced the distributor and still no luck....interesting to note that it will run on starting fluid ....and....now the fuel pump doesn't cycle off after several seconds like it used to....I'm thinkin' fuel pump relay (I don't know where it is to be found) and/or fuel pump?
Post Fiend
Joined: Mar 2002
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From: Bonita Springs FL
Very doubtful it's the fuel pump, but odd that it suddenly started doing this. You say that it doesn't stop running - is that right? The fuel pump just keeps running and running? If so, that's usually the sign of a bad PCM.
More Turbo
Joined: Jan 2012
Posts: 629
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From: VT
I had that exact same problem with mine last fall. It would randomly die on me when I was driving down the road. I went through the entire fuel and ignition system with no luck. Then it dawned on me that if I had fuel pressure and spark that it must be the injectors or the engine computer. I didn't think all eight injectors would go bad at once, so I took the computer apart and there was tons of corrosion in it. Replaced it with one from a junk yard and it runs fine now.
Like Andy said, I would think your pump is fine if you are getting good fuel pressure.
My pump did the same thing with the abnormal cycling / not cycling before replacing the computer.
What engine do you have?
Like Andy said, I would think your pump is fine if you are getting good fuel pressure.
My pump did the same thing with the abnormal cycling / not cycling before replacing the computer.
What engine do you have?
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'88 f350 7.5 gas, c6, injectors not working
One day my truck just quit running, for no apparent reason. Fuel pump cycles at turn of key, It has spark, it has 45 psi at fuel valve on rail. Noid light on injector plug is steady dim with key on & dark upon engine cranking. Test light is ON on both sides of FI plug w/ key on but OFF when cranking engine. Does run on starting fluid. I replaced the EEC (w/used one) and still no good. replaced distribitor (w used one), no help. Replaced battery and put charger on it @ 10A . Now, at last report, Fuel pump doesn't cycle off after several seconds.... pump just runs and runs. Could this be a bad ground or a faulty pump relay...Calling all Ford gurus.....I need my TK running soon... Also..where IS the pump relay?
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Fleet Owner
Joined: Aug 2005
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From: Easton,Ks
Still sounds like a bad computer. Unplug the computer and turn on the key, if the pumps do not run then the relay is more than likely OK.
The fuel pump relay is the green bottom one and the Power relay is the brown bottom one on the drivers fender.
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The fuel pump relay is the green bottom one and the Power relay is the brown bottom one on the drivers fender.
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Elder User
Joined: Feb 2008
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From: ohio
Check the two ground wires at the neg terminal. They appear to come out of the core support near the battery. Does the check engine light come on but is dim when you turn the key to run? Also as described above check the wiring to the relays especially underneath them. They tend to fail,and usually when they do you will not have any check engine light with the key on run. I personally would put original eec back in and see where you are.
Post Fiend
Joined: Mar 2002
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From: Bonita Springs FL
If your pump runs continuously, your computer is fried.
Fleet Owner
Joined: Oct 2005
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From: Kentucky
For reference this is what is does: Fuel Injection Technical Library » Manifold Absolute Pressure Sensor (MAP)