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Help with GPR & battery voltage issues please!

K

KyleH

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Hey y’all, hope you may be able to point me in a better direction.. here’s my current dilemma:

Driving on the Hwy last week and the battery light came on.. it worried me because I was just having these issues coming back from a big trip… Realized the 12v lug broke off the alternator and had since replaced it. Well I must have not put back the wiring properly & noticed the 12V GPR line had almost melted to the exhaust.. I assume this could most definitely effect the charging system?

I have replaced the GPR line with new fusible link of proper gauges but was still having charging issues..I replaced the GPR on a whim - thinking it could be that.. but now the glow plugs aren’t firing at all..

Getting codes now (P0380//P1656) with the new relay wondering if it’s a bad relay… have done all the tests in my Haynes bible and all point to defective GPR which I find funny but these things happen…

Getting 12V to relay and it’s clicking but no voltage to glow plugs..
My batteries are pretty low too.. but don’t think this would effect performance of the GPR? But maybe the PCM ?

Have checked all fuses and they’re good. Truck starts just keeps a low voltage & I don’t drive it far or at all really at the moment..


I figure I should grab another GPR since it’s under warranty but don’t think my problems solved there.. unless just a weird sequence of burnt links/relay… Feel like I’m missing something here tho... Guess it could just be one bad ground? Any help is much appreciated guys thanks for reading !
 
ak diesel driver said:
I'd get those batteries charged up and then test things. PCMs don't like low voltage
Click to expand...

Absolutely what AKDieselDriver said.
Low voltage will destroy a lot of components.
Get them batteries at a full charge state before turning on the ignition switch again.
Low voltage from batteries reaching the end of their lifecycle took out the PMD on My truck.
 
Yup, charge them batteries. for the GPR power line, check your main under hood fuse box and see if one of those big fuses aren't blown. or one of the smaller ones that control the energizing of the relay. on mine I found one of the pcm fuses in there blown and apparently powered the relay too. truck still ran fine but was having to use a screw driver across the GPR to start up in the morning.
 
So I’ve noticed fiddling around under there that when I jingle the main harness wire where it splits for the crossover ECT … trips the GPR so I think I just have a short or something in the harness or coming out… Just gotta go through them all…

will also get the batts tested under load
But seems like another issue. Thanks for all your help guys! Will post updates soon…
 
KyleH said:
So I’ve noticed fiddling around under there that when I jingle the main harness wire where it splits for the crossover ECT … trips the GPR so I think I just have a short or something in the harness or coming out… Just gotta go through them all…

will also get the batts tested under load
But seems like another issue. Thanks for all your help guys! Will post updates soon…
Click to expand...

I agree, it may be separate issues.
 
So here’s the current update. Pulled the intake / turbo tube and can see that the top of my injection pump is leaking. Must have failed seal. This is flooding the sensor… could be on to something.. sucks I’ll have to repair the pump. Hope I don’t have to pull it all the way out :X
 
You can start the engine with the intake manifold removed. Just be sure to protect the intake system from any leaking fuel.
Have some pieces of plywood or board ready to slap over the intake if leaking fuel gets to the intake portion.
 
A runaway diesel engine would not be a nice monster to have to deal with.
Whatever You do, NEVER USE ANY PORTION OF YOUR BODY TO TRY AND SHUT DOWN A RUNAWAY ENGINE.
Sorry for yelling. Just needed to be sure that the warning is heeded.
 
Hahaha man thank you. I’m not super keen on terminology / parts but that may be it. The truck runs still tho…& when I pull that sensor from the IP it shuts off … I wonder if it leaking there would throw off the ground and effect the whole GPR / charging system? Needs to be repaired regardless… hekn frik
 
is it just leaking from where the snap ring is on the optic sensor? there is an o-ring beneath that. but you'll have to remove the top plate too in order to get at it. there are 6 torks head screws (one has a ground lead attached) carefully remove the snap ring first, then the 6 screws. slowly lift on the plate and once it's free from the IP then push in or down on the plastic sensor connector so that only the plate comes off. there will be a oddly shaped rubber seal under the plate, be careful with it because apparently they can't be had as a replacement part. the o-ring will be on at the base of the plastic connector of the OP (optic sensor).

make sure you keep ALL trash from falling into the IP as a single grain of sand getting in there can destroy the pump!

others will chime in to help give you better instructions, maybe even photos. one thing you can do is lookup youtube videos on doing the optic bump. ONLY use the videos as examples on how to remove and reinstall that plate and o-ring. DO NOT try the optic bump, as you will be in more hurt with problems!
 
one other thing.... the harness that connects to the OP... is there still a short looking extension with a little black square box in the plug? if so, that is a noise filter that has given many including myself random issues. remove it and toss it into file 13... the harness will connect directly into the OP.
 
dbrannon79 said:
is it just leaking from where the snap ring is on the optic sensor? there is an o-ring beneath that. but you'll have to remove the top plate too in order to get at it. there are 6 torks head screws (one has a ground lead attached) carefully remove the snap ring first, then the 6 screws. slowly lift on the plate and once it's free from the IP then push in or down on the plastic sensor connector so that only the plate comes off. there will be a oddly shaped rubber seal under the plate, be careful with it because apparently they can't be had as a replacement part. the o-ring will be on at the base of the plastic connector of the OP (optic sensor).

make sure you keep ALL trash from falling into the IP as a single grain of sand getting in there can destroy the pump!

others will chime in to help give you better instructions, maybe even photos. one thing you can do is lookup youtube videos on doing the optic bump. ONLY use the videos as examples on how to remove and reinstall that plate and o-ring. DO NOT try the optic bump, as you will be in more hurt with problems!
Click to expand...

That’s extremely helpful. Thanks for explaining it all. I was wondering if I’d be able to do it myself… to be honest I’ve tried to rebuild my turbo before & was unsuccessful. Thinking I may have better luck with this if I do my research and take time. I’ve contacted a local shop that rebuilds Them for parts & a quote on rebuild of that portion. I think I can do it myself tho…

I do not have a torque wrench/driver tho… is this 100% necessary to reinstall those torks??
Thanks for all the help guys!
I figure it’s a blessing I’ve got it apart and see the leaking diesel… it’s so slight now but an engine fire down the road would be devastating. This is a vehicle I travel/ live in.. converted school bus:p

I have noticed when I pull the sensor- the truck dies…which leaves me scratching my head as to why I’m having ground issues still.. when I play with that area I can get the glow plug to click rapidly…It’s hard to tell with my lack of professionalism, but it seems the two are closely related..

When I check resistance between negative battery post and cable I am getting .65 on auxiliary battery & ~ .26 on the battery in bay… Does this mean anything to you guys?
 
hmmm no
dbrannon79 said:
one other thing.... the harness that connects to the OP... is there still a short looking extension with a little black square box in the plug? if so, that is a noise filter that has given many including myself random issues. remove it and toss it into file 13... the harness will connect directly into the OP.
Click to expand...
Hmm I’m not sure exactly what you mean .. sorry to sound dumb but what is the OP? :X
 
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