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-   1999 - 2003 7.3L Power Stroke Diesel (https://www.ford-trucks.com/forums/forum31/)
-   -   Stumped (https://www.ford-trucks.com/forums/1535644-stumped.html)

axmrdr 04-13-2018 08:52 PM

Well the low voltage and tiny current that a meter uses to get an ohmic reading is nothing compared to the voltage and current of a dual battery setup pushing current to fire the glow plugs and a engine starter so that reading I took earlier is misleading. Never the less I am going to check out the ground connections. You're right, it could cause other problems.

I suppose reading the GP again with the VC off would be a good idea before I make a final decision. ;-)

"Check it to both batteries, maybe one (the one you checked) battery has a bad connection. "

You have a good point. I didn't try both batteries, will do it in the morning.

Tugly 04-14-2018 07:31 AM

Two years ago, I ohmed out the grounds to each battery. The passenger side battery was fine - not so much with the driver side. I have since been on a "clean the grounds" binge, and I completely replaced the positive battery cable assembly and starter. After 19 years, that was some good medicine.

I would ohm the glow plugs through the valve cover gasket connections. The Under Valve Cover Harness (UVCH) is one of the most commonly replaced parts on the 7.3L, ask any Powerstroke or Navistar shop.

axmrdr 04-14-2018 08:21 PM

OK, cleaned grounds. Found number 5 glow plug with no reading to ground (taken from UVCH plug as advised). All others read 1.0 ohm to ground. Hooked up ammeter to brown wire and energized - 69 amps, yellow wire - 75 amps. The math doesn't quite work out but not going to worry about that,this tells me that 7 of my glow plugs are working. Not the cause for not starting. Either the harness is bad or a glow plug is.

However when I tried to ohm out the coils of the injectors the readings on the passenger side were pretty consistent but on the driver side readings were all over the place. Could indicate a bad harness or injectors.

I tried to do the cody test but it seems that you need to have the covers off to be able to tell anything. I had more chores to do than 1 man can get done in one day so I didn't have time to get the VC off.) I couldn't hear any leaks but without the VC off I probably won't.

When I released the air from the passenger side it puked oil back out as I have read the warnings posted here, but no oil puked out on the driver side. Is this significant in any way?

Since the harnesses are prone to go bad I'll be ordering a pair.

Tugly 04-15-2018 06:53 AM


Originally Posted by axmrdr (Post 17926508)
...when I tried to ohm out the coils of the injectors the readings on the passenger side were pretty consistent but on the driver side readings were all over the place...

There's your no-start.


Originally Posted by axmrdr (Post 17926508)
...When I released the air from the passenger side it puked oil back out as I have read the warnings posted here, but no oil puked out on the driver side. Is this significant in any way?

You're going to find out as you replace the UVCH on that side... when you repeat the Cody test with the driver side valve cover off - that sounds hinky. I'd order a full set of O-rings to go with the UVCH anyway... so you only have to wait just one dog year for parts instead of two.

axmrdr 04-15-2018 12:33 PM


Originally Posted by Tugly (Post 17927005)
There's your no-start.



...... I'd order a full set of O-rings to go with the UVCH anyway... so you only have to wait just one dog year for parts instead of two.

Already have received a full set (8) of orings, a tool for the HPOP lines and a 4K psi gauge and hose. Just ordered 8 glow plugs, 2 UVCH, 2 valve cover gaskets and an IPR pigtail. I don't want to go into this critter again anytime soon. It's still less than 1 truck payment.

I am going to rig the new IPR pigtail up so I can energize the IPR without having to rely on the IPC to power it up.(for any future diagnostic purposes - testing HPOP)

Don't know when I'll get 2 days off to devote some time to replace all of this. Retirement can't get here soon enough. When I find out what the problem is I'll be sure to post it.
I'm sure I'll have more questions before this is all done. Thanks

Bonanza35 04-15-2018 01:41 PM

Good luck. Will wait for your post.

Jaime74656 04-15-2018 02:50 PM


Originally Posted by axmrdr (Post 17916888)
Oil level is good, just changed oil - after truck died. I had the truck towed back to my driveway, shop is full of other projects so I'm relegated to working in the driveway for now..

I'll remove the chip as well, 20 minute job I can do today after work. Since you're here ;-) and you're the AE expert, what option in the drop down window do I select to get AE to see the high fuel pressure, I swore I have done it before but it's been a while since I used AE. I'm reading your AE class thread in between jobs at work but retaining everything that I'm reading is a bit overwhelming.

Presently working 12 hours days but as soon as I can I'll check wiring and do a Cody test. (I'll read up on that).


AE will not read FP on these trucks, same for EGT, if you need fuel pressure, either a test gauge at the fuel bowl or a more permanent hard gauge (pillar pod or similar) will be required, every thing else can be found with AE or Torque Pro (or The free edition of TP)

Tugly 04-16-2018 08:51 AM


Originally Posted by axmrdr (Post 17927533)
...I am going to rig the new IPR pigtail up so I can energize the IPR without having to rely on the IPC to power it up.(for any future diagnostic purposes - testing HPOP)....

I wouldn't. But if you do, just make damn sure the signal to the IPR is not connected to the PCM when you test it this way. The IPR is modulated, and the engineers made sure it didn't reach 100% duty cycle like you're doing. If you really want to troubleshoot the IPR... add a connector that allows you to check it with a meter while cranking, but seals from the environment any other time.

axmrdr 04-16-2018 12:34 PM

Until I read your response I was considering this for any future troubleshooting issues. ;-)

What voltage is correct? (voltage) without tuner and with? I can definitely add a way to test the voltage being applied to the IPR.

My initial thought was to throw 12 volts at it to check psi output of hpop momentarily (few seconds), is this a mistake? Wouldn't this eliminate the HPOP and IPR issues during troubleshooting?

By blocking one side at a time and checking pressure (using ICP and PCM this time) on each side for oring leaks? Please tell me if my thought process is wrong.

I see that riffraff has plugs for the quick connects on the pump, I'd like to make it so my pressure line had a quick connect also so I could more easily test each side and have ability to test dead head pressure as well if needed. Do you know where those fittings to do this can be purchased reasonably? I'm terrible with plumbing terminology so please make it simple. This is what I have .

The way I see it any money spent on diagnostic tools is in reality saving me time and expense later on.

hydro man 17 04-16-2018 02:14 PM

There is a company called hose & fittings. They seem to have most anything in that category you could think of. Prices seem to be in line but I have only purchased a few thing from them.

axmrdr 04-16-2018 07:38 PM

Thank you. After extensive searching to the far ends of the internet it appears that no one else in the world has used the quick connects on the pressure gauge so it must be a bad idea. I can use what I have, it will just take longer.

Walleye Hunter 04-16-2018 08:00 PM

I put together an STC (I think it is) to NPT adapter so I can connect my air hose to the HPOP hose then open the valve on my air hose and have no mess. Let me see if I still have the pics.

Walleye Hunter 04-16-2018 08:24 PM

I am not sure that I am following what you are looking to do. Here is a picture of what I use to test my HPO rails. I have an extra HPOP fitting, that screws into an adapter that my air hose quick disconnect fitting fits into. I cut a notch in a circular saw wrench with a dremel drill and it works great to disconnect the HPOP hose at the pump. I hook my air hose up and can apply all the pressure my compressor will muster without making a mess. Other fittings are available and if you want to build a different setup you should be able to do it.

https://cimg1.ibsrv.net/gimg/www.for...3a5c64a7bb.jpg

axmrdr 04-16-2018 09:55 PM

That is very clever. It's not what I am trying to do but I still will copy your idea and build one. lol thanks!

I was trying to use the quick disconnect fitting like what is on the HPOP line to hook my pressure gauge up to for quickly changing configurations to test the HPOP supplying oil to each side (individually) or dead head the pump. The only quick connect fittings I see for sell are the lower halves, not the top like on the hoses.

I suppose I could get a HPOP oil line and get a fitting like you have a picture of and fit it to my gauge on the other end ? Just wondering if it would be worth the trouble since I haven't found anyone that has done it. If it was a great idea, I figured that I'd see some how to's or parts lists out there to make it.

I can just unscrew the lower half of the quick connect and screw in the fitting that's on my gauge to the HPOP. Slightly longer and harder to get at but not unreasonable. Your wrench idea is a good one too.

Walleye Hunter 04-16-2018 10:30 PM

Here is a whole heap of options for you, the ORB to STC adapters are around page 27. Then you can get ORB to NPT adapters to get your other fittings to connect. I have a hydraulics shop near me that happened to have everything I needed in stock. If you have an idea and it works for you go for it, that's all I did, nobody else pieced my set up together either but it works well for me.

STC fittings


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