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Discussion Starter · #1 ·
New Here. Hope the experts can help.

Last week was driving down the highway when my truck felt like it lost power. I pulled off the road, it was barely running, sounded like it was not getting air or fuel. I immediately got check engine light. (My Torque Pro App can't read codes.) I shut off the truck and inspected. No visual problems found. It restarted but ran like it was losing power or not getting enough fuel, rough idle. I was able to limp it home and parked it. The next day I tried to start it, it cracked but nothing else! Had a small amount of clear/white smoke, "diesel smell exhaust." After doing some research online I went down the long list and started checking sensors. Checked the oil level, good. Checked wires in and around the HPOP and Valley. Multimeter drop test GLow plug relay, its working, test light tested glow plug wiring harness on valve covers. Checked for wires rubbing, nothing. Checked IPR Valve was tight, removed and cleaned ICP sensor. Good amount of oil in the ICP connector. Tried starting while it was unplugged, nothing! Turned it over with the ICP removed from engine and some oil came out slowly. I read the oil should have shot out of the ICP hole in the head with more force. So I started to suspect the IPR was bad. ICP definitely was bad.. re-installed the ICP sensor and it started go figure but ran like crud. Pressing the accelerator just boggs it down.. Any new ideas would be greatly appreciated. I don't believe it is my injectors because I had fuel cups and new O rings done about 2 &1/2 years ago. Today I installed a new ICP sensor and wiring connector. Nothing! Same crank no start. However now I have a check engine light. Purchased FORSCAN and Tomorrow I'll see if I can read the error code. If there is anything else I need to try before I move forward with purchasing a IPR Valve please help if you can.
Thanks MJS.
 

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Should have checked fuel pressure first.

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Discussion Starter · #3 ·
Should have checked fuel pressure first.

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What is the best way to test fuel pressure on a truck that won't start? Do you test while cranking the engine? Are you eluding to a specific problem for fuel pressure? What is your opinion on fuel pressure regulator screen?
 

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You can use a regular stick type tire gauge on the valve stem on the right side of your fuel bowl you should see about 25 psi while cranking and about 50-60 psi when it's running. Wrap the tire gauge with a rag so, you don't take a fuel bath.
 

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There's no valve stem on the right side of the fuel bowl on a 2003. There are two ports in the back of the fuel bowl. You'll need an adapter to access them. Here's a link - 1/8" NPT straight pressure port adapter. There is a picture of the ports on that page. The port on the left of the housing is "pre-filter" and the one on the left is "post-filter".

Then, you can put a Schrader valve assembly ( Fuel rated Schrader valve for testing fuel pressure. Rated for Diesel or Gas. ) into that fitting, or you can use an oil pressure gauge (they rent them at Autozone) or, preferably, put your permanently mounted fuel pressure gauge sender there. Every 7.3 owner should have a fuel pressure gauge anyway.

Fuel pressure should be around 60 psi with the key on. Our trucks have an electric fuel pump so you don't need to crank it to test.
 

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Sorry. about the misinformation mine is a 95 I just assumed that all 7.3l were the same. My bad...
 

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You had a check engine light come on, so there should be codes stored in the PCM. Post those and we can let you know where to start.

You can do a quick and dirty fuel supply check by opening the filter drain valve and turning the key to ON. You should see a healthy stream coming out of the drain tube. (Catch it in a container to keep from making a mess.)

Oil in the ICP connector may mean the wiring there has deteriorated. You may need to replace the connector pigtail.
 

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Discussion Starter · #11 ·
So I had a gut feeling the aftermarket CPS was junk. So I gambled and bought another one from Ford this time. After making sure I had fully charged batteries I tried to start and it fired up but ran roughly then it got a little smoother but still not normal idle. One error code showed up p1316. Online says one of the causes could be the DIDM (Diesel Injector Driver Model) hope you really smart Diesel Heads can help me again. Could it be air in the lines that needs to be worked out?
 

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It may take a few dozen miles of hard driving to purge the air out of the high pressure oil gallery for it to run right.
 

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DTC P1316 means there are codes stored in the IDM. You need to run an injector buzz test to get it to cough up the codes.
Generally points to a problem in the wiring, often the Under Valve Cover Harness coming loose. There's a slight possibility that the IDM is bad, but don't just swap it out, as the possibility is very low. Also something to check is where the harness crosses the driver's side valve cover. If it's touching the valve cover the insulation can wear thru. An easy fix if you find that. Just tape it up and put something around it to protect the wiring.
 

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Discussion Starter · #15 ·
DTC P1316 means there are codes stored in the IDM. You need to run an injector buzz test to get it to cough up the codes.
Generally points to a problem in the wiring, often the Under Valve Cover Harness coming loose. There's a slight possibility that the IDM is bad, but don't just swap it out, as the possibility is very low. Also something to check is where the harness crosses the driver's side valve cover. If it's touching the valve cover the insulation can wear thru. An easy fix if you find that. Just tape it up and put something around it to protect the wiring.
It may take a few dozen miles of hard driving to purge the air out of the high pressure oil gallery for it to run right.
I hope that is all it is. But I believe klhansen is correct also. I just got done watching a video on that exact issue with buzz test and undervalve cover wiring harness came lose. I'm fingers crossed hoping I don't have to dive in to the valve covers and more wires.. I'll prob have to since its going to burp and hiccups until I do.
 

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Discussion Starter · #16 ·
You had a check engine light come on, so there should be codes stored in the PCM. Post those and we can let you know where to start.

You can do a quick and dirty fuel supply check by opening the filter drain valve and turning the key to ON. You should see a healthy stream coming out of the drain tube. (Catch it in a container to keep from making a mess.)

Oil in the ICP connector may mean the wiring there has deteriorated. You may need to replace the connector pigtail.
I replaced the ICP after it was saturated through with oil to the plug side. I also attached a new connector pigtail and checked the wiring and diagram twice. It started after that was done . Now it just rough sounding half running missing sound. Hope I don't have to go under the valve cover.
 

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