Code P1298 help

[94NAIDI]

Long story short. My wife’s 1997 7.3 powerstroke is having rough start issues. We originally thought it might have bad injectors but I trouble shot that down to 3 bad glow plugs and passenger side valve cover gasket plug has a burnt glow plug contact. I ordered Motorcraft gaskets, UVCH, and Alliant Power pig tails for both sides, and 8 Motorcraft glow plugs. This should fix the rough start issue. However, while troubleshooting, I put my Auto Enginuity scan tool on the truck and performed KOEO tests and pulled codes P1298 IDM Failure and P0605 Control Module ROM Error. But running KOER I do not get either of those codes. Also, this truck runs and drives perfectly fine once started and warmed up. So here’s my question. Could I really have a bad IDM with this truck running so good? Or could it still be bad injectors? Could the UVCH and gaskets possibly be causing these codes? Or are these just old codes that are no longer valid but are still in memory?

I also did the injector Buzz test and the injectors all sounded pretty much the same. They all buzzed at same basic audible level.

I’m trying to get this truck fixed and replace everything that is necessary. But I don’t want to waste money either. If it needs injectors, then I’ll buy them. If it needs an IDM, I’ll get that as well. But if neither is causing a problem, I don’t have money to waste.

What are your opinions on this? A truck that runs and idles perfectly but supposedly has a bad IDM according to the scanned codes. Seems odd to me.

I appreciate any help on this head scratcher.

 

[greenskeeper]

Did you clear the codes after installing the new parts? The IDM code is probably from the burnt harness and ROM error is common and means nothing.

Best mod I did for both my trucks was to put the GPR ground from the PCM on a switch with an LED light, that way I can see when the PCM is commanding the GPR to energize the glow plugs and turn them off when not needed. IMO the PCM excessively uses the glow plugs to limit cold start smoke at the expense of wear and tear on the GPR, GP, UVCH, and batteries.

 

[XOLATEM]

I second the practice of clearing the codes after you document them and then starting fresh with a drive cycle.

Then you see what comes back and then concentrate on fixing the condition that makes the code or other codes show up.

I might be fulla stuff...but I always had the idea that lingering codes may cause the computer system to modify its strategy to compensate.

If that idea is not in the realm of possibility...I would welcome some feedback from others still practicing in the field...

One thing I picked up from a friend years ago was not to panic and start buying a lot of stuff...but it is hard to resist when all you want is the problem to go away...

Wishing you luck on it...

 

[94NAIDI]

Thank you both for your input. I am still waiting for the gaskets, UVCH, pigtails, and glow plugs to arrive. Estimated delivery is around the first of February. Once those parts arrive, I’ll replace them and then see about clearing the codes.

I’m new to this Auto Enginuity scan software. When I go into the program it does a Code scan and comes back with no codes found. That same screen has a clear codes option. In order to perform the KOEO test, I have to go into the special functions screen and then it pulls up the above mentioned codes. I assume those codes are in memory somewhere. But I didn’t see an option to clear them on that screen. I’ll look closer once I get the parts installed and replaced.

My theory is if the IDM was truly bad, then the truck would run poorly and the codes would appear during the KOER tests. So I will wait and see if the gaskets and UVCH fix my cold start issue and then try to clear the codes.

I’ll let you know as soon as I get them installed.

 

[94NAIDI]

I received the parts and started the work when disaster struck. One of the glow plugs broke off in the head. I did eventually get it out, which I am going to create a new thread on that fiasco so that maybe my experience can help anyone else with my same bad luck. Now that I have overcome that issue, I will be getting the UVCH, and pigtails installed. Hopefully today or tomorrow.

 

[Black dawg]

Have seen a couple with that code recently. Both ran fine, both code would return, rebuilt idm and no codes.

 

[94NAIDI]

Did you rebuild the IDM yourself? Or did you send it out to be repaired?

 

[Black dawg]

Used rebuilt idms.