'94 6.5 eprom

[daCat]

I recently dropped a new engine in my '94 2500 and installed a rebuilt IP. I keep seeing code 36 with my Engh Motors diagnostic software and have been told the problem may be caused by the eprom not matching the rebuilt pump. As the story goes, the '94 pump was replaced with a slightly different model that will retrofit, but only work properly if you also change the eprom.

I've checked and added extra grounds, fuel system, filters, timing set, and stood on my head and spun both clockwise and counter clockwise with no measurable results.

Still get a code 36 and slow pedal response, and after warming up a surge at idle...sometimes.

I'd like to find a stock eprom that will work on my baby.

[DmaxMaverick]

Welcome aboard!

The 1994 model year is unique, in regards to pump compatibility. The OEM HD EEPROM (8600 GVWR and up) will only work (properly) with the 5068 pump. The use of any other pump will require an EEPROM upgrade, of some sort. You can either use one from a 1995 model (make sure the powertrain is the same), or several aftermarket options that address the issue.

This does not apply to 1994 LD applications (C/K 2500 w/7200 GVWR, or C/K 1500), or any other year model.

[daCat]

My truck is a 1994 C 2500 ext Cab w/ 8600# GVWR
6.5 turbo diesel 4spd auto 4L80E

It now has the DS4 5521 pump in place of the DS4 5068.

I'd love to find a stock eprom that would work. You say a '95 model is correct?

Where can I lay hands on one of those?

[DmaxMaverick]

Wrecking yard first, if you want an OEM solution. KennedyDiesel(.com) can do it for about the same price aftermarket, which will work with any other pump. You can also request some custom options, if you have some specific needs. If you use an OEM EEPROM, make absolutely sure the powertrain is the same. An Automatic tranny program won't work with a manual, and vice versa. Ultimately, it's best to have a custom program sourced, and Kennedy can do that. It'll cost less in the end. The 5521 pump is much improved over the 67/68, so you should take advantage of that. Fix it now, or revisit this issue later.

[daCat]

Not sure what issues you are referring to, but I don't use my truck to pull a load on a regular basis, and generally not long distances then. It has served me well completely stock, and for now, that's all I want from it.

I've entertained punching it up a bit, and may again. But if I do, I'll do the whole bag, 4" exhaust, bigger turbo, inter-cooler, water injection, marine pump and injectors, etc along with a high performance chip. At this point I can't justify all that. And it is an old truck. I've taken care of it well, and will paint it again soon, but at age 59, I'm not going full steam myself anymore, so we kinda match.:D

[daCat]

Bought a computer at a local salvage yard that came out of a '95 C3500, installed entire unit. Started like a new one, instant fuel pickup, shifting normal, and power to go!

Excuse me while I do the happy dance.:)

[16gaSxS]

Bought a computer at a local salvage yard that came out of a '95 C3500, installed entire unit. Started like a new one, instant fuel pickup, shifting normal, and power to go!

Excuse me while I do the happy dance.:)

:D I am glad the salvage EPROM worked! :cool:

Welcome to Da Diesel Page.... :)

[daCat]

Half of the top of the eprom was cutaway. It acts like it's been modified. Timing set to spec and yet it reverts to 8.5 on it's own. Shifts quick and smooth unless I put my foot in the radiator, and downshifts a bit faster too. Turbo spools up faster than I remember as well. When I kick it, I get some black smoke.

And thanks to you and CC for the welcome. I think I'll like the neighborhood.