Hello everyone! I finally took the leap and bought me a diesel. It is a 2002 F250 4x4 7.3L with 157,000 miles on it. I just bought this thing 2 days ago. For starters, my wife's nose is already bunched up because it looks so nice & sits pretty high. So subconsciously, she's already "against" it. I digress! Anyways, onto the problem. This morning, when I started it, it seemed to "clank" a little. It was like 25 degrees outside. Not too horrible. After the glow plugs cycled, it fired right up with no effort. I let it warm up so my wife could take my son to school. Funny how she "hates" my truck but still wants to drive it! She called me and said the thing is shaking and bouncing around and that it has no power. She brings it home and the check engine light is on. The cheap O'Reilly scanner only gives me code P1316. After some research, and some mildly aggressive texts to the previous owner, I decided to investigate myself. I tried to clear the code, and it said "code clearing failed" or something of the sort. Upon research, I discovered that the most apparent cause of this problem is the, correct me if I'm wrong, the IDM module coming unplugged. Let me back-track for a minute, the previous owner said maybe I should try starting the truck in "GP Tuner Level 1" so, I did that, with no adieu. So, after fiddlin' around with it, I got out the old water bottle. It was doing as I thought and the right bank (drivers side) wasn't firing. The manifold was merely warm. I shut the engine off. Searching around the top of the engine, I wiggled the wiring harness plug in that goes into the driver side valve cover. I made sure it was snug & flush. Then, on the way down, I noticed I had a little bit of bugs/leaves in my K&N Air filter. I picked them out, and on the way down, I pushed the yellow "air restriction" button. It clicked. I got down, went inside and got my keys and came out to start it and it fired right up. No codes, no misfiring, no problem(s) whatsoever. Will someone please tell me what I did to bandaid this issue? Did I temporarily re-seat the wiring harness into the IDM Module, do I need to take of the valve cover to inspect the IDM? Any and all help is appreciated. Thanks in advance!!

 

The IDM is inside the drivers fender well, behind the liner. What you may have done is reseated the connector to the valve cover gasket, where all the wiring for the injectors and glow plugs go. It's more common for it to come loose on the inside of the gasket, but it's not impossible for the outer connector to loosen up. You may want to pull the connector and inspect it for any signs of heat damage. The glow plugs draw a fair amount of current and can heat the connector up if the connections aren't secure. If the symptoms return, try wiggling the connector with it running and if it clears up, there's your problem.

If that looks OK, you may consider pulling the valve cover and checking the connector on the inside as well. It's a common problem, and there is a mod to help keep the connector in place called, "the 50 cent mod."

 

Pikachu>> Thanks! Obviously, it is not the IDM what I am referring to. The module I am referring to is under the valve cover gasket. Well, let me rephrase that, the "plug-in" I am referring to. I've researched the mod you're talking about. The one I reseated was on the outside of the valve cover, with nothing removed. I drove this thing home 1.5hrs, it has big tires and hit a few dirt roads on the way. Could this've caused it to unplug? If so, WHY on the FIRST day I own it!!!! LOL

 

Of course the first day! You'll wrassle with it, assert your will, and from then on that pony will know who's in charge.

P1316 typically pops up when the harness under the valve cover wiggles loose. It can come and go as the connection makes and breaks. Looks like you figured out it is th driver side already by the manifold temps. Check out a 50 Cent mod thread

Btw, the drop into oem box type K&N has a bad rep. If you clean and oil religiously they are ok, but if you blow it off... bad juju. Also clips on oem air filter box break, and unfiltered air can dust the turbo, something to be aware of.

 

Well, it lasted about 10 days and then it happened again. No codes this time. Of course, I didn't drive it as far. In case you're just starting to read this, I'm talking about an apparent P1316. My driver side injectors stop firing. As aforementioned, no codes this time. So, I tore it apart to do the "50 cent mod." When I get the valve cover off, there is no separation or unplugging of the harness. In fact, its still clipped tight & intact. Since I've got it off, I'll probably go ahead and disconnect it and check the terminals for corrosion, shorting etc.. My question now is, where do I go from here? I'll check the "outside" plug as well. All thoughts are appreciated! Thanks!

 

Hey man try this test below...

https://www.ford-trucks.com/forums/8...ly-please.html

It helped me when I had an intermittent p1316

My number 5 injector wire pin was bad inside the UVCH this test helped me find it! Also there is another good test that I am trying to find that starts at the Injector Control Module (IDM) I think its called... the giant plug that is under the drivers side wheel well. Testing from there first can narrow some things down.. Let me see if I can find it.

good luck!

 

Here's a pinout of the connector at the IDM. This is looking at the connector with the wiring harness coming out to the right, so flip the diagram upside down if the wires are to the left, like they will be if you disconnect it and slip it out from behind the plastic fender liner.

 

Ya that's the one!

Really helped me out!!

 

Well, after some testing, here are the results. I'll need your help to interpret please. All injector wires/connections test out within spec. Glow plugs 7,5,1 test out ok. Glow plug 3, I get 0ohm (no reading) on my voltmeter while probing thru the top (outside) of the harness. When I disconnect the UVCH and probe it, I get between 1.5-2.2ohm. My conclusion is that the harness is bad. The question I have is, could/will the short in the #3 glow plug cause the entire bank to shutdown? Also, it might be redundant, but does the glow plugs run all the time?

 

No, depending on engine oil temp, they run at initial key on engine off, (when you first turn the key forward, but don't actually start) up to 120 seconds, if it is very cold even after the truck starts, then shut off. You have something else going on. I would inspect the drivers side harness very closely. There may be a chaffed wire there shorting on the valve cover or somewhere else.

 

I broke down and bought a new VC Gasket/Wiring Harness'. Installed and it seems to have cured the problem. It has however, popped a code. I'll get it read in the morning.

 

It runs just fine now, however, the code is a glow plug code. I think I didn't get a boot on #6 glow plug seated. I'll tear it back apart I'm the days to come & let y'all know!

 

Cool, let us know.

 

I tore it back apart last night & re-seated all the glow plug boots. On #6, I pinched the female connector tighter together. The code light has went out & the problem has seemed to resolve itself.

 

Just a few things Ive learned in the two years ive owned a 7.3..

If/When you do glow plugs only use MotorCraft.
I used Autolite and in 8 months I couldn't get them back out they were already so swollen. Wish I woulda read about the issue first.

Only use International or Ford Crank/Cam Pos Sensor. Not worth doing every 90 days no matter what the warrenty is.

Check the sensor on top the Driver Side head for seepage in the Plug. Keep it clean. Leakage means its going bad and its an expensive little bugger. (ICP).

Read up on that K&N. Not a good choice for our engine. I have on my gassers so im not a k&N hater.
I love my 6637 DIY MOD. Its how I found this forum when my wife broke my Airbox "trying to HELP"

I'd nut and bolt all the Clamps on the turbo system. Blown off boot means wife on side of road because of a loose 10mm nut. Be Sure. I wfas not so smart...lol

RiffRaffDiesel.com is your friend. Hard to beat prices and knowhow... Ive Tried.

Before you do any PERFORMANCE mods. Get Gauges First...

Good Luck and welcome to the SD 7.3 Family