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Codes 34 and 94?

6.5TD Burb

6.5TD Burb

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Location
Wendell, NC
There was a whole 'nother post here but I did a little more homework and fixed a couple problems. Anyway here are the two that I'm getting. I know the 34 is the stepper motor but what is 94?

Is the only solution to 34 replacing the stepper motor?
 
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try here main page--http://www.troublecodes.net/GM/


1994 diesel specific--http://www.troublecodes.net/GM/94-95_65.shtml

did you replace IP yourself? bleed injectors, set timing-and at what?
 
I did replace it myself...only one way to learn right?

The system was bled but probably not the right way, seems to run fine though other than the above problem codes and related problems.

I set base(?) timing according to the mark on the flange of the IP and mark on the timing cover. Don't have anyway to check desired/actual(?) timing yet.

Code 94 - Cylinder balance fault = out of time IP?
 
code 94 is misfire in cyl. #4
Probably air from the IP change working it's way out.
 
Is there anyway that the 34 and 94 codes are related? Will changing the stepper motor in turn fix the misfire?
Seems to be a possibility since the stepper motor controls (at least to a degree?) timing? Maybe my logic here is flawed; still learning.....

So should I let the truck idle for a little longer see if it works it's way out?
 
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Forgot to add something. Tapping the accelerator will turn off the CEL, wait a couple moments and it will come back on at idle. Anyone? I'd really like to get this thing running right by Saturday night at the latest. Right now it's sitting outside just idling; seeing if that does anything.
 
10-4, still no joy. I have also found out that I have a rather massive fuel leak which may be the problem with misfire. I guess I'll know tomorrow after I pull the intake back off and check all the injector lines and return lines for leaks. I was really hoping to spend the last day of my vacation week relaxing; bummer.
 
Update: Problem found! Injector line on cylinder 6 was loose. Still have the stepper motor problem though. Hopefully using my old one will not void the warranty.
 
Suburban is back together and driving. Drives good. 11psi at about 3/4 throttle, maybe less and EGTs never got above 400 cruising @ 50mph. Excellent. Only one problem; I still have that code 34. I replaced the "new" stepper motor with the old one off my core IP and still the same results. Cleared the code/s several times and it still comes back. It seems to take longer at a stop now for it to come on though. With any input/output of the APP the light will go off. When cruising @ 50 the light did come on. After the test drive/fill up sitting in the drive way and holding the RPMs at 2300-2500 for several moments the light did not come on.
 
It may need a TDC Learn to zero in the stepper, it might be operating out of range.

Leo
 
Ive had a code 34 since I did my IP, I know the timing is off, its loud when its cold.. Is your timing ok?
 
Base timing is as far as TDCO/other Idk it's at one of my customers' shop now. The PMD was just a random thought/question.
 
If anyone was actually curious: problem fixed; WAY out of base timing. Using the mark I was told to use on the IP, base was about 15* advanced....maxed out on the IP. Reset to 10* and the light is out. Not quite as peppy and a little harder to start in the morning with more white smoke but at least it's a lot quieter and no more CEL.
 
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