Rough running 7.3 and lacking power

blaze42069 · May 10, 2016

So my 97 has been rough running last 2 yrs and it's getting worse. I have AE and have run the typical tests. I buzzed test injectors and all sounded the same. I just changed oil with no change I used Rotella 15w40. I failed the cylinder contribution test on cylinders 1,2,6+8 and got a 1298 idm fault as I had a modified idm. I removed and put in a 2002 idm and the 1298 went away and I failed 1,2+8. I ohmed out the injector harness and had no issues there. I know this engine has low compression in some cylinders and has bad blowby. But if I had a mechanical issue I would have a rough running engine all the time. Right? The truck starts quick and strong everytime. I also have an aeroforce scan gauge and when I start the truck it works perfectly, then I drive the truck and the rough idle comes in and the gauge starts getting lines in it to the point I can't read it anymore. I contacted aeroforce and they said I have an electrical interference somewhere to cause their gauge to do this. I do get occasional check engine light that goes away on its own and can get no codes with the AE. It rough runs with and without the check engine light on I do still see codes from my mods. Ebpv etc.
I do not have the 50 cent mod done on the uvch. Could the shaking engine cause these to loosen up when running yet still be connected when engine off. I did new uvch and gaskets 6 yrs ago when I installed rosewood 160cc remaned injectors and the 17 degree hpop hits 3000psi when I punch it. The icp sensor is 2yrs old and I rebuilt the ipr about 6 yrs ago. At idle the icp bounces 150 psi when running rough or not. I still have the old black cps.
Any suggestions on anything else I can do with the AE? Thank you

blaze42069 · May 13, 2016

Nobody has any ideas hey. This site used to be the best to help me fix my truck but for this old platform I guess no one really pays much attention to it any more. I know it's a tough one. I might have to simplify it and do the Cummins swap thing. I know, I know let the flaming begin.................

ullover:

79jasper · May 13, 2016

Ohm out the harnesses.
Do some actual diagnosing instead of relying on computers.

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blaze42069 · May 13, 2016

Thank you for the help. And if you read my first post I did ohm out the harnesses. This is intermittent, like a loose wire shaking. I wiggle on the harnesses and pigtails of all the sensors. I have wiggled and jiggled everything and nothing changes. Turn off truck go inside for an hour and then come out and it's a 50/50 shot it does it again or not.

79jasper · May 13, 2016

Ohm it while jiggling harness?

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blaze42069 · May 14, 2016

79jasper said:
Ohm it while jiggling harness?

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I will try that thank you

uncool · May 14, 2016

So you truck has been running like sh!t for two years and is getting worse? Huh, go figure.

Since it has only been 4 days since your post and nobody has fixed it for you yet.

So 6 years ago you installed rebuilt injectors and rebuilt your IPR, been fine for 4 years, now issues come up.

If you say you have done all the diagnostic work, pull the injectors and send them in to be looked at, buck up and buy a new IPR and go from there.

blaze42069 · May 18, 2016

uncool said:
So you truck has been running like sh!t for two years and is getting worse? Huh, go figure.

Since it has only been 4 days since your post and nobody has fixed it for you yet.

So 6 years ago you installed rebuilt injectors and rebuilt your IPR, been fine for 4 years, now issues come up.

If you say you have done all the diagnostic work, pull the injectors and send them in to be looked at, buck up and buy a new IPR and go from there.

Whoa big rig drop the testosterone. What's there to figure about uncool? I'm here looking for help not cutting anybody down. This is the thing and your right. I have to start looking at the injectors and other parts. Which I'm doing. It's just where I live no one knows much about these old girls. Hence the reason I'm here. I didn't think of changing the ipr but I will now. It's just so intermittent that if it was mechanical you would think it would happen all the time. My ipr #s seem to be in line but maybe I'm missing something. And will try that thank you. And if I annoyed u in some way I got 2 words for ya.............. ha ha.

superpsd · May 18, 2016

I would change the CPS first it's easy and cheap. A fluctuations of 150 psi is not good. The IPR should be able to maintain ICP within 20-40 psi. Maybe a new IPR is in order. You may also have injector issues. Maybe pull the valve covers and measure armature clearance or just pull them and have them gone thru.

Outlaw7317 · May 18, 2016

blaze42069 said:
Whoa big rig drop the testosterone. What's there to figure about uncool? I'm here looking for help not cutting anybody down. This is the thing and your right. I have to start looking at the injectors and other parts. Which I'm doing. It's just where I live no one knows much about these old girls. Hence the reason I'm here. I didn't think of changing the ipr but I will now. It's just so intermittent that if it was mechanical you would think it would happen all the time. My ipr #s seem to be in line but maybe I'm missing something. And will try that thank you. And if I annoyed u in some way I got 2 words for ya.............. ha ha.

So your POS truck runs bad for 2 years and you keep on driving it, surprisingly it gets worse and your in awe. Then you come charging in here saying this and that about the site, shooting people down that try to help you (regardless of weather you already did what they are recommending or not), and basically tell someone else, offering to help, to get ***ked?

People like you have been the demise of this site.

The way you post, your sig, and even your avatar, scream flat bill coal oraler. I really don't give a chit if your truck gets fixed or not. Put a Cummings in it and go to CF and hang out.