2001 7.3 wont start when cold

97cherokee

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hey guys so my 01 7.3 wouldnt start the other weekend when it was 21 out.... so i verified that the glow plug relay was working by making sure it has 12v across relay for atleast 30 seconds and it did, i moved on to ohming out the glow plugs and found two dead on one bank. so i ordered new uvchs, motorcraft plugs and a stancor relay. got the driverside valve cover off and found that i had pinched the back two glow plug wires between the valve cover and cyl head when i was checking for my idm failure a few motnhs ago... replaced all the plugs, harness's and relay. well this morning it was 23 out and low and behold she wouldnt start. just like before every time you try and start it trys to catch but just wont, light fuel smoke while cranking and cold out... injectors are swamps and around 3 yrs old with 75 k on them, engine does not have any fast spots in it, no oil usage, doesnt smoke unless im on the throttle or lugging the piss out of it, batteries are good, voltage is good. around 12.5 on both sides of gpr... im still leaning towards the gloe plugs not getting juice though. is it possible that the wiring being shorted to ground caused a meltdown elsewhere????? the connectors looked good. thanks for the help and merry christmas!!!
 

97cherokee

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so i jsut checked power at all 4 gp pins on both sides at main connector... i have 12v. a friend is reomending that it be checked at the uvch though....
 

97cherokee

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they are dorman gaskets, ive had pretty good luck with them asideds from where i pinched the one... so im pretty much at the point of pulling the valve cover back off and verifying power to the the gp???
 

ncollins64

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I’ve seen a lot of “glowplug, injector” problems and they all had dorman gaskets. Changed to alliant/motorcraft gaskets and injector harnesses and those gp and injector problems went away. Use motorcraft for anything electrical on these trucks. Just my .02
 

Dave_Nevada

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I’ve seen a lot of “glowplug, injector” problems and they all had dorman gaskets. Changed to alliant/motorcraft gaskets and injector harnesses and those gp and injector problems went away. Use motorcraft for anything electrical on these trucks. Just my .02

I can verify this too. NEVER use Dorman gaskets. Those are 100% Chinese crapola.

I went through hell with this nonsense with Dorman gaskets and then I bought a set of the Ford brand.

You aren't saving any money by buying Dorman. Time is money, and my time is worth a lot.

Your time? Well, you have to decide what you're worth.

Live and learn.
 

psduser1

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I’ve seen a lot of “glowplug, injector” problems and they all had dorman gaskets. Changed to alliant/motorcraft gaskets and injector harnesses and those gp and injector problems went away. Use motorcraft for anything electrical on these trucks. Just my .02

I can verify this too. NEVER use Dorman gaskets. Those are 100% Chinese crapola.

I went through hell with this nonsense with Dorman gaskets and then I bought a set of the Ford brand.

You aren't saving any money by buying Dorman. Time is money, and my time is worth a lot.

Your time? Well, you have to decide what you're worth.

Live and learn.

.....
 

97cherokee

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ok guys, well when i get the chance friday i will verify that im not getting any power to the plugs and then comp check it. if i see that im getting power and check comp and its in check ill change out the harness's any way and see what happens
 

97cherokee

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what should voltage specs be??? also i will be checking amperage draw on glow plugs today, what should i be seeing??? and i believe good compression is 350, acceptable is 320 plus if i remember right.
 

Arisley

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Voltage should be closer to 14 VDC.

Turn the key on, watch the volt meter, not the wait to start light. When the relay opens, you will see the volts come back up. Cycle the key again and the relay will close again. If your batteries are a little bit tired, running the glow plugs, firing the injectors (powering the IDM) and turning over the starter makes it a lot harder to start these engines.

I once had a problem with my truck. Batteries were tired, bought new ones. Had 14.7 volts at the batteries. Only 12 and the GPR. Ended up having to replace the positive battery cable.

You can special order it from O'Reilly's, you have to find a guy there sharp enough to look at the books instead of the computer.
 
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97cherokee

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from what ive read everywhere else its supposed to be around 12v with minimal drop across relay
 

97cherokee

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well i checked glow plug amperage draw- starts out at 160amps, which indicates all plugs functioning. pulled passenger valve cover and checked compression. found between 380-430 on a semi warm block. will update with cold block comp numbers tomorrow.
 

DEEZUZ

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You won't see 14v unless engine is running and alternator is charging.

Almost never do I have above 12v when working on anything. As long as it matches battery voltage and that's above 10.5v, no worries
 

DEEZUZ

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well i checked glow plug amperage draw- starts out at 160amps, which indicates all plugs functioning. pulled passenger valve cover and checked compression. found between 380-430 on a semi warm block. will update with cold block comp numbers tomorrow.

No need, those numbers are good. Move on
 

DEEZUZ

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While cranking, are you getting good solid clacking from injectors?
 

97cherokee

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well rechecked the one banks compression this am.... and shockingly the compression is between 380-410!!! damn thing has 350k... clacking.... not sure of. i do know that i do have a little bit of fuel smoke. im starting to lean towards injector issues now.
 

DEEZUZ

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That's where I was at. Asking if your injectors are clacking good while cranking
 

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