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94 6.5 vin F bad injection pump?

Rebellion97

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Hello I am new to the site have looked through alot of threads and YouTube. I am new to diesel world my 94 has a new lift pump starts kinda rough with some white smoke at first will run strong most of the time will have a power issue now and again idles high all the time between 1800 and 2100 and after warm up it will stumble or "miss" at idle runs good other than between the 1800 and about 2200 range when going through the gears haven't found anything on my particular problem to much the filter is new by the looks ik the govner and idle is all controlled inside the actual injection pump it has no high idle switch either that ive found it is also a manual
 
I have not yet just got it a week ago and still trying to figure things out and but will do that and idk why the truck won't let me read the codes I've done the data link connector where it should flash 12 and the codes but I can only get it to flash once
 
PMD is relocated forgot to mention and looks like only 1 injector has been replaced in a while truck has tons of power when it idles between 1500 and 1700 until I shut it off then once started back its random that it will idle slightly less but then I won't have the power
 
Was it 94 or 95 that the ignition switch caused freaky events? The temp sensor is popping up in my head too (I am heavily distracted right now so someone jump in if I am taking him down a rabbit hole.

Have you removed, cleaned and reinstalled the engine grounds? Especially the one on passenger rear..
Then do battery connections too, including the stupid puck spacer between cables if it hasn’t been converted to top post batteries yet.
 
Was it 94 or 95 that the ignition switch caused freaky events? The temp sensor is popping up in my head too (I am heavily distracted right now so someone jump in if I am taking him down a rabbit hole.

Have you removed, cleaned and reinstalled the engine grounds? Especially the one on passenger rear..
Then do battery connections too, including the stupid puck spacer between cables if it hasn’t been converted to top post batteries yet.

Yea all grounds seem good and yes the sister batt is a top post it dont have that puck thingy
 
Welcome to the truck stop.
Just cause the grounds look good doesn't mean anything..unbolt them, clean good and reinstall...I learned that the hard way.. these engines are finicky... That ground cable to back left side be tranny dipstick grounds alot of stuff and can have corrosion between connectors... ignition switch can cause prob, to. But you really need a clear fuel line going into the pump so you can see if there's any air in it..cost 5 bucks to do and takes less than 5minutes... Alot of guys on here will chime in soon, listen to them, there the whole reason my truck still runs...
 
Any DTC? On a 94, you need paper clip to read the code.

Check the FFM for leaks which usually not making it to the ground?

Check the hoses to and from the FFM?
 
@Will L. 94 into early 95 build dates had that crappy ignition switch that would cause all kinds of mystery electrical/running/nonrunning problems. The switch itself down on the lower steering column, NOT the lock cylinder you put the key in. They also had that APS/ECM disaster early in the 94 MY run that caused runaways and resulted i cessation of production mid-year until the slide rule guys could figure it out.
 
I forgot to ask you, @Rebellion97, is your 94 Vin F a 3500? They used two different IP's on the 94 M.Y. 3500s - they both look identical and bolt right up and will run, sorta, but internally their electronics are different and send a different signal picture to the ECM. The model number on the pump is crucial when getting a new replacement pump in order to get the correct computer-compatible pump. This was a 3500-series, 94 year only thing.
 
As usual, OP has not come back?
OP ? and i ended up going through again on all grounds lines codes codes cannot be read still dont kmow why it may need to be flashed but as for my main problem done research and am confident that my issue is the IP bc of the flutter ut has between 1300 and 2200 rpm and the inconsistent "misses" it has
 
OP = original poster.
I would do an Optical Sensor test as well as a Crank position sensor test. To do an OS test unplug the CPS and then try and start the engine, it will take alot of extended cranking and when/if it starts it will be in limp mode. Assuming it starts it should run smoothly with no hiccups or issues. If there are any issues at all it indicates a bad OS or wiring associated with it. To do the CPS test you unplug the OS and try to start it, everything should be the same as with the OS test
 
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