hey guys!
so last year I put all new injectors in my 7.3 and there has been one that has been missing or acting up ever since. also replaced the norm,( wiring harness etc). So I have put about 750 miles on these new injectors(only ran it a little because the rear end went out) and I finally took it to my mechanic today to pull the codes from my check engine light to see if we could find this problem.
1.P0381- Glow plug/heater indicator circuit
2. P1395- Glow plug monitor fault(bank 1)
3. P1670- electronic feedback signal not detected.
please help me get to the bottom of this thanks!
-justin

 

If the engine runs then ignore the P1670 code. Nothing to see there.

The other two codes point to a GPCM issue.....which means you much have a California truck since it's not too common for a pickup to have a GPCM.
You should browse down to the Excursion forum and do a search for those codes and see what you find. You might need to replace that control module but I'd hate to see you start replacing parts before you research a bit further.

Since you have the 'emissions' hardware version of these trucks....your PCM should also be able to capture Freeze Frame Data. Did you mechanic download any of that info? If there are no other codes, then your SES light is due to the GPCM issue.

Can you describe the 'missing' or 'acting up' injector symptoms? It's very rare to have issues with a brand NEW set of injectors. If they are remans, then it's possible one may still have an issue. Where did you buy your injectors?

 

It is a cali truck and the injector is making a tapping sound. I did talk to someone who rebuilds idms. They said It could definitely be the idm throwing that code and causing that injector to fail.

 

Yes it can...

I replaced a good injector thinking it was bad becuase the IDM had developed a short. I pulled codes time and time again and the answer was staring me in the face the entire time. There was a code that straight up said "Bad IDM".

I replaced it with a rebuilt one and haven't had a problem since.

Like the FICM on the 6.0, I killed mine with loose battery connections and weak batteries.

 

It is possible the injector is loose or loosened up. The glow plug code can be from a loose connection at the uvch (50 cent mod should have been done when it was apart, maybe it was?) or a wire rubbed on a rocker. Or just a bad glow plug possibly?

Or it all could be just from the loose connection. Or the possible bad IDM.

Personally I would loo at the connection at the valve cover harness on bank 1 (where the problems are coming from). If the outside plug is good and no burnt pins I would pop the valve cover and check the underside connection, wire harness for rubbing, and check the torque on the injectors on that side.

 

well i think its the idm since the P1670 code is pretty obvious but i cant do anything untill my new starter comes in which should be in the next week so i will try and find a donor idm in the mean time so that i can test it ill be back with updates

 

ok guys so i put a new starter in(only took 2 months dam amazon) anyways much better starts lol so i took my idm out today and the pins look good clean as hell actually but my new idm is on the way so ill post updates later about the status.

 

ok guys new updates,
new idm didnt do anything still have an injector tapping. also when we did put in all the new injectors we also put in the upgraded wiring harness. just a thought i wasnt there when the injectors were put in but when you go online to look for injectors there is a special injector i guess for the number 8 cylinder? could this injector maybe been put in the wrong cylinder and that is why we are hearing this tapping and getting these codes? please help thanks.

 

could this be a bad idm relay? just wondering thanks!

 

No. If your engine runs then your relay is working.

 

I was pretty sure your IDM was fine....

Some engines shipped with an AE type injector in the #8 spot and it's designed to help with a 'cackle' issue. Did you have your original injectors rebuilt or did you buy brand new? Kinda hard to make helpful suggestions unless we know what you did exactly.

If I had to throw a dart at something....I'd lean towards Snowseeker's advice in post #5. It's possible the tapping sound you are hearing is a loose injector.

 

It's a 7.3, injectors make noise. It's a diesel it makes lots of noises. Have you done any supporting fuel mods? I suspect you have air in your fuel system. Search hutch mod and frx if you haven't done so. Stop throwing parts at your truck

 

ok guys new updates! so today i took the truck to my mechanic and guess what? P0381 and P1670 codes are gone! seems like the new idm did fix some stuff but i still have a p1395 code now this is a believe to be a California truck wasn't there some setup on a relay that had something to do with the glow plugs? also my mechanic said maybe its worth it to go to the ford dealer and have the reboot the pcm and etc what are your thoughts? thanks!

 

also guys information that i didn't put i just today replaced the glow plug relay. the truck doesn't even have a glow plug monitor? why would a glow plug monitor plug come up?

 

Look at the passenger side of your motor near the front of the turbo, right below the CAC tube. If you have a large 3" silver rectangle with a green and black plug going in the bottom you have a GPCM.