6.5 Turbo DTC 44 & 45

[Turbomax]

I've just purchased a 1995 Turbo 6.5 truck. The SEL comes on & goes off. On more than off! When the SEL comes on, the cruise quits working. I took it to O'Riellys & they scanned it. Said it had 2 DTCs. 44 & 45. I've spent all my money on buying the truck & can't afford to start throwing parts at it. Please help. The man I bought it from said it has a 1997 engine in it. Will that make a difference on the codes? I appreciate your help. Thanks

[JohnC]

44 and 45 are EGR codes and shouldn't have any effect on the cruise control. Search this forum for more info on how to deal with the egr.

And, Welcome!

[Turbomax]

Hey John, thanks for your reply. However, this truck does not have an EGR. So, what do you think the codes mean? Thanks again

[JohnC]

this truck does not have an EGR.

Did it ever? the non-EGR PCM shouldn't ever display EGR codes.

[Turbomax]

I'm not sure. The truck VIN has an F for the 8th digit. I spoke to the guy I bought it from & asked if the 97 engine had an EGR. He said no. I asked if he changed the ECM from the 97. He said no, that he used the 95 ECM. I know very little about this stuff but would assume that it did not ever have an EGR.

Thanks for your interest & help.

[DmaxMaverick]

If you are seeing 2 digit DTC's (codes), it's an OBD I computer (94-95, NOT a 97). It does seem as though it has an S code computer. Otherwise, you wouldn't be seeing EGR codes. Some 3/4 ton trucks and Suburbans were delivered with S code engines, so even if the computer was from another 3/4 ton, it may be an F code engine/VIN, but with an S code computer. The cruise control issue may be indicative of this, as the F code computer incorporates PTO function (if enabled), and can interfere with S code cruise function (CC controls engine speed during PTO use). I've seen this before on 1995's.

[Turbomax]

Wow! I had no idea that I was buying such a can of worms. Any suggestions as how to make this truck run with the SEL off & the other stuff working correctly? Thanks.

[Robyn]

This indeed can be a can of worms.

If the rig runs well otherwise, I would call Bill Heath and explain what is happening and see if they can fix you up with a new "Prom" for the ECm that has the EGR function disabled as well as the defuel function also eliminated.

At this date, I am going to bet that there is a possibility that the Prom may have been swapped out for whatever reason and possibly the wrong one put in.

Now, was the fellow you bought the truck from the original owner (from new)

Things have a way of getting changed over time and once things happen, many times the story and info get lost along the way.

Take a look at the LH valve cover towards the rear, an F code engine should have one solenoid there, this runs the turbo wastegate.

If you find two solenoids, then the second one is for an EGR (that may have been removed)

Someone early on could have swapped out the air hat on the manifold with a non egr one.

By chance is the a "California" emissions equipped rig.

A light duty 3/4 ton could have been set up with S code controls, then lost some things over the years.

I have owned several F code Burbs and never seen an EGR on any of them.

Swapping out the Prom for one that does not have all the extra controls will solve the issue.
You dont necessarily need to spec out a performance prom, but just one that will stop the unwanted SES stuff.

Keep us posted

Missy

[Turbomax]

Thanks Missy for the info. I've sent an email to Bill Heath but have not heard back from him yet. No, the man I bought the truck from was not the original owner. He said he bought it about 6-7 years ago. Apparently it needed the engine swap when he bought it. He was a GM mechanic somewhere in the St. Louis area at the time. I don't know if he bought the entire 97 donor truck or just the engine & trans. I know what you mean about stories/memories getting garbled over time. Mine sure have! I looked for the solenoids you suggested. I only found the one with 2 vacuum lines - 1 goes to the waste gate on the turbo. I suppose the other goes to the vacuum pump??? I don't know if it was ever California legal. The man that I bought this from said the SEL had only been coming on for about a year & that he had driven it very little during that time since he had bought a D-Max. Is it possible to send my ECM to someone & have it reprogrammed to the settings I need? If so, should the SEL go off or at least give me a code I can understand? What will it cost? Or, do I need to try to find a 97 ECM? Again, what should that cost? I'm not looking for a race truck, I just want many good, dependable & economic miles. One more thing: when I start the truck first thing in the morning, I have to crank it a few more revs than when it is warm. But, it smokes like crazy for about a minute. It does not burn oil or lose water so I'm assuming the smoke is fuel. Is it possible that one or more of my injectors are leaking down over night? After the smoke clears every thing seems to be normal until the next morning - except for the SEL & no cruise. You mentioned a S code engine. I assume that an F code means no EGR. What is the S code? If I don't know the VIN from the 97 how will I know what code the engine is? Thank for everyone's help. I really appreciate it.

[Turbomax]

OK, here's the latest. The original codes I posted were from an O'Reillys hand held scanner that apparently couldn't actually read the failure codes. The truck DOES NOT have an EGR. I took the truck to a diesel shop & the codes are: 35 - Injector Pulse Width Error - Short Response & 36 - Injector Pulse Width Error - Long Response. The mechanic did find some ground wires on the back of the engine that were suspect. He repaired those but nothing changed on the codes. He suggested that the probable cause of the codes was due to a injector pump solenoid failure & that it was not replaceable. He said I need an injector pump but he could not definitively guarantee that would cure the problem. I have the injector pump from the donor truck but don't have any way of knowing if it is any better than the one that I am running now. I called a rebuild shop & they said they could test the pump but that it was possible for it to pass their tests but, in fact, not be any better than what I have when installed & put into actual operation. I have replaced & relocated the PMD w/#5 resistor on a heat sink so I don't think that is the problem. Please help! BTW, when I pulled the old PMD off the injector pump, it did not have a resistor.

I have read a little about the possibility of replacing the electronic injector pump with a mechanical pump & eliminating all these problems. I would greatly appreciate y'all jumping in & giving me some advice... how well does the conversion work... what pump do I look for... how difficult is it to do, etc. From what I have read, the injector lines will have to be changed. If I can find a donor with a mechanical pump, will those injector lines work with my engine?

As stated earlier, I am not looking for a high performance truck, just one as close to original operation as possible. I just need dependable transportation that I don't have to keep putting $$ into.

Thanks again for all your help.

[a5150nut]

when you moved the PMD, where did you mount the ground fo it?

Ground needs to be to the pump, not the PMD.

DB2 is the mechanical pump. Requires pump, lines, and throtle cable.

[Turbomax]

I left the ground on the pump & mounted the PMD behind the license plate

[Turbomax]

Yee Haw! Finally got the 6.5 running the way it is supposed to. The 2 mechanics I went to suggested that 35 & 36 codes (both injector pulse width) may point to a sensor inside the injector pump. According to all I could find, it is not user replaceable which meant a new pump. I don't have the $$$ to roll the dice on an injector pump. I found one in a salvage yard. The truck had only been there a short time & I verified from the previous owner that the pump was good. I removed the pump & took it to a mechanic to install. He only charged me $90. Got the truck back yesterday. No codes; the cruise control works perfectly; cold starts - no smoke or hesitation. Thanks for all your input. I appreciate it.