97 7.3 diesil, issue is this, at idle it tends to hunt a little, running from 580rpm to 680rpm. Also in the last 10,000kms the power seems to be dropping off. At idle it sounds like I have an improper injection as it will miss a little on one cylinder..........smooth out and idle awsome for 15 seconds, then misfire a little again on one cylinder for 45 seconds.

Fresh oil every 5000kms, new fuel filter, air filter.............cleaned the screen on the FPR. dont get me wrong, still pulls real good but its just does'nt have that extra get up and go like it use to have.

What I've noticed, I had about 4000lbs of sandbags in the box of my truck(dually), if I let off the brake and idle it it'll creep foward on its own but not with out the front end bouncing up and down on one paticular power stroke.........and it sounds like I have one injector thats not firing properly from the sound of it. Would a bent flex plate do this(e4od trans), being replaced

Last to note, the injectors pass contribution tests and buzz test but still kinda has a missfire that clears up once and a while so it does not sound like compression issues. My oil level is correct so no fuel in the oil as well.

I hope I explained what I've done clearly.

Engine has 210,000kms on it, nearly all highway pulling a 5er

 

Unplug your ICP on the front of the left (drivers) head. (Three wire connector). The PCM will go to a default setting. If it smooths out, replace the ICP. Check the connection and timmerman nut on the IPR (left rear of the HPOP). Check your fuel pressure at the schrader valve on the FPR (should be 40-60 psi stock).

 

fuel presure is at 58psi....

HPOP=high presure oil pump?
whats ICP and IPR

I searched Alldata for those abreviations and cannot find

 

Here's a good site for info on these trucks. You may want to bookmark it.

Thanks to Steve Baz

http://pages.prodigy.net/stevebaz/_i...az/index3.html

 

At Idle thats O.K.

Yes, high presure oil pump, located on the rear bottom of the HPOP reservoir, which is located in the front valley of the engine, just infront of the fuel filter housing.

ICP = Injector Control Pressure sensor (it reads the oil pressure in the heads that fire the injectors).
IPR = Injector Pressure Regulator, screws into the bottom left rear of the HPOP, has a two wire connector. (it controls the pressure of the oil in the heads that fire the injectors)

Also might want to check out this site: http://www.intellidog.com/dieselmann/home.html
It has alot of good info on it and explains how the engine operates.

 

YEAH, THAts at idle, thanxs for some of the info, I'll have to look further into it when I get my transmission back from the shop and I throw it back into the truck.blew the converter seal and lost my oil and found my flex plate was bent so thats coming new too as well as changing my ball joints and front u-joints. As well as throwing on a down pipe off the turbo...........just droppping some money into it cause its been trouble free but these little things have been poping up....except for the transmission thing, not excatly little. When I get her going this weekend I'll have to try look into the engine.

For the hell of it, should I just change my injector O-rings just because???? Gotta get in thier to change my glow plugs, it feels I got some that are not working like they use to. All original, engine never opened

 

Probably shouldn't bother. When the injector o-rings seep a little it will put out a puff of blue smoke every time you start it. When one is blown it puts out clouds of smoke and hammers like it's coming apart.

It may need fresh injectors, but from what you've posted so far I don't think the injector o-rings are part of your problem.

 

I would not change the injector orings unless I knew I had a problem with them. JMO. Do a search for post by tjbeggs, awhile back he did a good post on ohming out your glow plugs, injectors, valve cover and under valve cover wiring. Could save you alot of time, trouble and money by knowing which ones are bad which ones are good.

A bend flex plate can cause an engine to run rough/out of balance. This could have been some of your problem. Try it with the new new one installed and let us know if you have any more problems. Alot of knowledgeable poeple on this site and are willing to help.

Good Luck.

 

Its does do this...........I asociated it with my glow plugs cause its getting harder to start(have to cycle the plugs a couple times or just wait beyond the light)

 

Any links to a half decent OEM injector or a mild upgrade that you guys have had good fortunes dealing with???

 

This is where I will get my next set of injectors from:
http://www.beansdieselperformance.com/

 

Here is the info i gave to someone else that plowhand was talking about for testing injectors wiring and glowplugs:

You can check all of the wiring with an ohm meter before you pull valve covers. if any of the injector wiring it over 3 ohms you have an issue there. to test just measure resistance between the middle wire of each plug and the wires on each side.

so heres what the connector looks like

1 2 3 4 5
- - - - -
1 and 5 are glow plug terminals and 2 and 4 are injector low side wires and 3 is injector high side (common to each injector). So you will test between the high side and low side of each injector for less than 3 ohms. More than 3 ohms is bad. And test glowplugs for less than 20 ohms between battery ground and the glowplug terminal. More than 20 ohms and either a bad glowplug or bad wiring.

that should get you started. Are there any codes or even a check engine light?

 

My injectors came from Diesel Innovations.

Scroll down to the bottom of this page http://www.dieselinnovations.com/di....products&cat=2, you can get brand new Alliant Power (OEM) for $284 each or all 8 for $1936.

You can get a set of mild performance or stock injectors for less money, but they will be remans....not that it's a bad thing. Plenty of folks around very happy with their remans.

 

No CEL....but awsome qwick check for the wiring, going to do that as well as check the sensors in past posts


Wont check engine till least middle next week, gotta finish the ball joints, front u-joints and still waiting for the transmission to comeback, should be ready monday........getting the transmission shift kitted with new torque converter seal that leaked and bushing(bushing walked figuring related to the bent flexplate)

 

I did these test and everything checked out now, when I unplugged the ICP the idle dropped a little, picked right up and idled the same, otherwise the nuts is tight and connection is good.

Have to check the wiring now...............

Otherwise, the shift kit is working nice, everything is firmed up and I also my selinoid pack in the transmission has a circuit board on it, my shift pattern is changed now, seems to be pretty nice.

As for the lurching and up and down under start up from dead stop, pretty much all gone, I suspect the flywheel was the culpret.

Unfortanitly I think I got to change my torque converter, has a bit of a shudder now when I really load it up which I've never noticed before cause I never really do a stall test.

Lastly, anybody that is not running a down pipe, replace it WOW. huge difference.

Like mentioned, have to check the wiring