I'm not sure where to start with this, especially since I've never worked with any modern auto electrical system. My service engine soon light came on yesterday picking up my kids from school. I got home, plugged in the Bluetooth adapter, and brought up Forscan Light. To make sure there weren't any codes lingering from the past, I cleared and reloaded it all.

Here's what It says:

P0672 No. 2 Glow Plug Circuit - malfunction is confirmed.
P1670 Electronic Feedback Signal Not Detected - Powertrain Control Module
P0470 Exhaust Back Pressure Sensor Circuit Malfunction
B1352 Ignition Key Circuit Fault

Tax weekend, so will be looking more at this in the new week. I'm not sure where to start on all of this. Is there some controller that all of these codes could be wrapped all together with a malfunction? Some time ago, the hpop blew a leak and made a mess of the engine compartment (and elsewhere). I cleaned it all out the best I could gently do.

The truck starts and run as normal if you ignore the SES light.

Would this post be best at home here in the 7.3 section, or electrical?

Thanks,
Ryan

 

Hi Ryan. I’d say the 7.3 section is the place to be.

I’m not a code expert but there are others here who are and will be along to help.

I’d probably start by looking at the EBP Sensor wiring.

 

First thing I'd do with this is pull the EBS, ohm the sensor to see if it's still good, clean the tube and sensor. The tubes will typically rust through where they go down through the a/c tensioner brackets, but if you look up from under the truck you should be able to see it. If you do need a new tube, get the stainless steel unit so it doesn't happen again. Dorman makes a fitting for where the tube hooks up to the passenger side exhaust manifold if that's in bad shape too...

 

What is the year, model and mileage of your rig? From your profile, I see you are in CA, and have 2001 F350 with 150K miles or less. Is that correct?

That P1670 code can eventually cause a stall or no-start, and is sometimes due to a wiring/connector issue between the PCM and IDM. You can wiggle the harness while she is idling, and see if it hiccups. Or pull the PCM and IDM connectors and trace the affected wire with a multimeter and watch for an open circuit.




With the glow plug issue calling out #2, it looks like you have a GPCM. My guess is this is what set off your SES.



Start by checking the resistance of the glow plug through the valve cover harness, or at the relevant GPCM connector. It should measure 0.5 to 2 ohms.





I've attached the GPCM pinpoint test procedure from our Tech folder sticky - give it a try.

 

Yes, correct, though it's about 155k now.

Thanks everyone for responses, you've given me good starting points. I'll be checking in this thread coming week and keeping it updated.

What a coincidence that I just received my registration renewal notice on Friday. Really want to avoid having to take it to a shop as that reg fee is enough on its own in this state.

​​

 

CA smog is a no go with a CEL.

Where are you located?

 

I think that's with most states...

 

Visiting this again.

I've got a larger socket coming so I can get that sensor off. All looks pretty straightforward to check, clean and/or replace on this. The whole thing is clean so it could just be a clog.

New error code popped up B1203 Fuel sender short to battery.

Resistance at glow plug connector pin to ground was 1.3, so would need to go further...for today I've gotta leave in this afternoon again so I'm not getting to that valve cover.

So weird all of these codes cascading. There were none a couple months ago, and it doesn't get driven much.

Anyway, I haven't had any time since this first post to even look at this truck except today, and I can't even see me being able to take care of this in any timely fashion. Just bad timing I've seen somewhere on this forum Orangevale Diesel recommended by someone at some point, so have made an appt to drop it off there on Wednesday. I get out of having to take autos to mechanics a lot, but sometimes it's just not feasible.

Thanks everyone for helping. I will update this with how it goes.

 

Thanks for the update! Good luck!

 

Cascading codes, any evidence of mice? Sometimes they like to chew on wires.

 

That P0470 points to an electrical problem with the sensor/pigtail or associated wiring I think. Another check to confirm would be to look at EBP_A and MAP PIDs in FORScan/FORScan Lite with the key on engine off, and see if they match within 0.5psi. If the EBP sensor has not been replaced in its history to this point, it's not a bad idea to change it out with one from a reliable seller like RiffRaff or dieselorings.




That B1203 could be the overhead console computer starting to go bad. It uses signals from the tank sender to calculate range. I had similar fuel tank sending codes. Resoldered some loose resistors and it cleared the code and brightened the display.

That glow plug resistance value is good. If the connector pins look ok, you could move the wires a bit while taking the measurement, see if it flickers open or shorted. Clear the codes, and drive it again, see if the code returns after the next drive cycle or two. If it does, it might point to the GPCM. Its rare for the PCM to be the cause.

 

No rodents around here as far as I've found. Though I think a cat or squirrel ran away with one of my traps Inside of the truck has no evidence...

 

Thanks for the response!

Thanks for mentioning the overhead computer. That IS something I feel more comfortable looking at, so will see what the board is looking like.

So I've heard back from Orangevale Diesel. Seems the glowplug connector needed repaired. After I had pulled the connector, and checked resistance, the code hadn't stayed cleared so I just decided to take it in. The day I started it to drive it over, no SES light. They sent me a picture of this gasket from the connector. All fixed I guess. I think it mentioned other codes were dealt with so I will see what's left over when I get it back.

They said the EBP should be replaced, but I think it's worth seeing if it is clogged anyway, and can easily replace the sensor (I have a socket for it now). This is something I can do with an hour of free time on the street. They also said the WIF light was flickering which I hadn't noticed, but quoted $230 for fuel filter change. I have one here already and can drain and replace that and see if that light still shows up. Another thing I can do with just a little spot of time.

They found a nail in one of my front tires that I didn't know about, so will need to get that patched. Dirty air filter, which I have one here.

I AM getting the rear brakes done so still good I took it in. Down to 2mm.

 

By the way, I thought I'd mention I often pick up parts off of ebay. I go for OEM sales from overstock, closeouts, etc, and can return if I don't like what I get.

The EBP is pretty expensive most places (the shop wanted $163 to do the changeout. assuming most of that was part cost too).

There are 5 sensors left in this listing. https://www.ebay.com/itm/355573433575 at under $16 OBO.

Cheap enough to just get one and hold onto it until needed. They came very well packaged, padded, inside individual boxes, inside original motorcraft baggies. There are other listings for cheap as well, but I was specifically pleased with this seller.

 

I bought the back pressure sensor and the IPR valve.
will throw them in the part drawer.