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Confused about Why It won't Start

For whoever it was that suggested the wastegate, etc., I ruled out all that by removing the turbo plumbing so it could suck fresh air without the turbo. Still no start, so anything turbo related can be ruled out.

I will check on the glow plugs/fuel ideas the next time I get out to the truck, but the PO just put new glow plugs in it and verified 12V going to them, so the relay must be good.

I'm still confused, because if the truck is hot, it shouldn't need the glow plugs to start and I know the light doesn't even really come on when it's hot, so I would think that glow plugs aren't the issue. Either way, I'll check them out.
 
To verify there is fuel pressure with the engine idling, just open the T-valve on the T-stat xover and if fuel is gushing out at a good rate then your LP is running. If there is no fuel and a vacuum and truck dies then the LP is not pumping.

If it wont start I would unplug the OS and try, but it almost sounds like you have some electrical issue that keeps the SES light on that may be preventing an inject signal when cranking. But maybe the PCM responds once RPMs are high enough from using ether. You can check to see if the inject commands is being sent. Here is a good thread about it taking electrical measurements. http://www.thetruckstop.us/forum/showthread.php?23904-jump-A-B-13-not-12-Poppet-Valve-IP-Question

And again, if you had new glows and put a 100A jump starter on it, that runs off AC power then you could have fried the glows. If the truck is warm it should not need the glows, but you should still get a glow light for at least a few seconds. If you dont then you have an electrical problem.
 
If you did not remove the jumper in pins A and B then it will cause the SES light to stay on, and is not good to crank or run the truck like that.
 
OPS is Oil Pressure Sensor and NOT Optical Sensor.

OPS runs the LP while the engine is running. During crank, it is run by the relay.
So, the LP may be running when you crank but at the time engine started running the OPS took over.
(This is for OBD-I truck, e.g. 93-95)

If your OPS is in-op, the LP will not run hence no start.

Let's try to put 12V source directly to the LP and see if you can start. If you do, LP is good but chances are OPS is bad. So replace the OPS with original ACDelco OPS.
If not, then you have other problems.

Long term solutions will be to put a relay to override the OPS portion that runs the LP but let's just get the truck started first.

Also LISTEN to TurbineDoc!!! He is one of the best and experience 6.5 member in dealing with 6.5 Diesel engines.
 
OPS is Oil Pressure Sensor and NOT Optical Sensor.

OPS runs the LP while the engine is running. During crank, it is run by the relay.
So, the LP may be running when you crank but at the time engine started running the OPS took over.
(This is for OBD-I truck, e.g. 93-95)

If your OPS is in-op, the LP will not run hence no start.

Let's try to put 12V source directly to the LP and see if you can start. If you do, LP is good but chances are OPS is bad. So replace the OPS with original ACDelco OPS.
If not, then you have other problems.

Long term solutions will be to put a relay to override the OPS portion that runs the LP but let's just get the truck started first.

Also LISTEN to TurbineDoc!!! He is one of the best and experience 6.5 member in dealing with 6.5 Diesel engines.
Concur with all the above with the additional advice of getting a known LP pressure reading while running at idle and being driven.
Working through the check list here: http://www.thetruckstop.us/forum/sh...c-Troubleshooting-Checklist&p=73211#post73211
and posting up the results will help as well.

Where did you purchase the truck, this issue sounds very familiar....
 
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Hey did you buy psychobilly's truck?

Yes, this is psychobilly's old truck. Truck has no rust with the exception of a couple bubbles on the drivers door. It appears to be original paint. I figured I'd get it running and put a new bed on it (other than a ding, this bed is in great shape but it'll be easier to change the bed than to deal with changing a bedside). Only other thing I could find is it has the clear on the hood peeling. It's in really good shape for a '94, so I decided to get it from him and fix it up.

I'm a big fan of diesels and have had several....7.3L powerstroke, 6.2L, and of course VW diesels. I think I have plenty of info here to get started but since it's at a friends house, I only have limited time to deal with it. I will definately check everything you've suggested but it may take me a week or so to get around to all of it. I'll report back anything else that I find.
 
First thing you have to find out is if there is fuel from the lp while it runs. If not then the IP is pulling the fuel from the tank but may not be able to pull it to start. Could also be fuel draining back to tank, possible check check valve failure in LP?
 
First thing you have to find out is if there is fuel from the lp while it runs. If not then the IP is pulling the fuel from the tank but may not be able to pull it to start. Could also be fuel draining back to tank, possible check check valve failure in LP?

I can't remember if it was on his thread or the phone but IIRC, PsychoBilly said he wasn't getting fuel to the injectors while cranking....
 
I can't remember if it was on his thread or the phone but IIRC, PsychoBilly said he wasn't getting fuel to the injectors while cranking....

I can't remember if there were any answers to the suggestions given in that thread.

If it will run after starting on ether it must be getting fuel.
 
Make sure the Lift pump is pushing fuel all the way to the IP with the engine off... just because it purrs doesn't mean it works. If you don't have fuel, it won't go.

NVW said:
If it will run after starting on ether it must be getting fuel.

It's been said, but bad glows will do this. Try the hair-dryer thing. If it starts on hot air, it's a glow plug issue.
 
I can't remember if there were any answers to the suggestions given in that thread.

If it will run after starting on ether it must be getting fuel.

No answers to his thread, he ran out of time and $$$ and had to sell.
As for my statement about the no fuel at injectiors while cranking, I was in full agreement with your post:
First thing you have to find out is if there is fuel from the lp while it runs. If not then the IP is pulling the fuel from the tank but may not be able to pull it to start. Could also be fuel draining back to tank, possible check check valve failure in LP?
Writting being the worst form of commo, I'm sorry if that didn't come across in my statement.
Additionally, the truck's batteries were questionable as well but with $$$ running short, PsychoBilly couldn't get them changed out either.
There is a spare LP that was included with the sale, it might come in handy. Didn't want to blow my horn but to quell the doubt on the spare LP's functionality, it was the one I swapped out when I did the Walbro change. Nothing wrong with it, I just had the Walbro sitting there and the OEM LP took up less room on the shelf and PsychoBilly had a need....

On Edit: The Farmer who owned the truck prior to PsyochoBilly obviously neglected the maintenance on many levels and so I assume there may be several contributing factors to the truck's issue. Running down the known good parts via the diagnostic check list (batteries load tested, GPs checked not only for voltage but continuity, LP jumped and tested for PSI, funny smelling fuel etc) will help isolate the causes and allow for effective repairs. At least we know the PMD is OK.
 
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Make sure the Lift pump is pushing fuel all the way to the IP with the engine off... just because it purrs doesn't mean it works. If you don't have fuel, it won't go.



It's been said, but bad glows will do this. Try the hair-dryer thing. If it starts on hot air, it's a glow plug issue.

The thing is Jim, it won't start warm without ether.
 
No answers to his thread, he ran out of time and $$$ and had to sell.
As for my statement about the no fuel at injectiors while cranking, I was in full agreement with your post:

Writting being the worst form of commo, I'm sorry if that didn't come across in my statement.
Additionally, the truck's batteries were questionable as well but with $$$ running short, PsychoBilly couldn't get them changed out either.
There is a spare LP that was included with the sale, it might come in handy. Didn't want to blow my horn but to quell the doubt on the spare LP's functionality, it was the one I swapped out when I did the Walbro change. Nothing wrong with it, I just had the Walbro sitting there and the OEM LP took up less room on the shelf and PsychoBilly had a need....

No problem Paul, I know what you meant. I was stating it as a ? as much as a statement. It really is hard to guess not being there.

I have one other thought. My 97 was bought for parts but the guy I got it from said it would run. I checked the compression and it's at 125 psi for the 5 easy cyl. to check. I think he poured the ether to it and screwed the rings or something.
 
Yep, sounds like no fuel to me, too, but that was already asked and discounted, as I read it. That's why I suggested looking for fuel at the IP, not the FFM.

AND ... warm doesn't mean squat if the fuel won't atomize. Crappy compression, slower than optimal cranking, cold air and it won't go then, either. Even with fuel.

If the thing has been starting on ether, and has been boosted with 100A AC Charger, both of those things are possible. Not sure about ambients where the OP is ...
 
I'm bored and can't sleep so I decided to do a little research to bring all up to speed on what has been done to this truck since December.

Looking back through PsychBilly's thread"
-Code 12 when jumping the pins...
-"I only got fuel to the t-valve when the engine is turning over good. When the batts were weak I got no fuel to the valve."
-"I tested the LP pressure and it's only making about 3-4 psi. It also took it about 40 secs to pump a quart out the t-valve."
-All eight GPs did eventually get changed with 12v at all eight. WTS light was staying lit for up to 15 seconds.
-One battery was down on CCA, 450 vs 600.
-Cracked a line at some of the injectors and no fuel during cranking.
-Did not swap in a different lift pump

Pneese973 has:
-code 12 when jumping pins...
-started the truck cold or hot on slight ammounts of ether
-charged the batteries with a 100A charger and jumped it with another vehicle
-Filter was bled with a bottle and clear line with small amount of bubbles observed
-ran the pump and got about a quart of fuel out of it and closed the filter drain with the pump running. No indication of the time it took to get the quart of fuel or whether the truck was running or not while being bleed
-"The lift pump will run when jumpered or I can hear it for a few seconds after I stop cranking, so I know it's running" (not clear if he was checking LP output during this process)
-Stated, "It can't be a bad lift pump or a hole because I get fuel out of the filter when I crack the bleader and run the pump-installed a new PMD on a remote to the bumper"
-unplugging (one at a time) the coolant temp sensor, IAT sensor, and the map??? sensor and tried starting it and no luck
-confirmed the weird smelling fuel PsychoBilly reported
-observed the truck has a funny smell out of the exhaust while cranking (like stale fuel) and "I saw smoke out of the exhaust while trying to start it"

Not sure if this helps but at least it gives a one stop reference point.

Besides, Pneese is obviously smarter than me, has logged off and is getting some rest.
 
I'm bored and can't sleep so I decided to do a little research to bring all up to speed on what has been done to this truck since December.

Looking back through PsychBilly's thread"
-Code 12 when jumping the pins...
-"I only got fuel to the t-valve when the engine is turning over good. When the batts were weak I got no fuel to the valve."
-"I tested the LP pressure and it's only making about 3-4 psi. It also took it about 40 secs to pump a quart out the t-valve."
-All eight GPs did eventually get changed with 12v at all eight. WTS light was staying lit for up to 15 seconds.
-One battery was down on CCA, 450 vs 600.
-Cracked a line at some of the injectors and no fuel during cranking.
-Did not swap in a different lift pump

Pneese973 has:
-code 12 when jumping pins...
-started the truck cold or hot on slight ammounts of ether
-charged the batteries with a 100A charger and jumped it with another vehicle
-Filter was bled with a bottle and clear line with small amount of bubbles observed
-ran the pump and got about a quart of fuel out of it and closed the filter drain with the pump running. No indication of the time it took to get the quart of fuel or whether the truck was running or not while being bleed
-"The lift pump will run when jumpered or I can hear it for a few seconds after I stop cranking, so I know it's running" (not clear if he was checking LP output during this process)
-Stated, "It can't be a bad lift pump or a hole because I get fuel out of the filter when I crack the bleader and run the pump-installed a new PMD on a remote to the bumper"
-unplugging (one at a time) the coolant temp sensor, IAT sensor, and the map??? sensor and tried starting it and no luck
-confirmed the weird smelling fuel PsychoBilly reported
-observed the truck has a funny smell out of the exhaust while cranking (like stale fuel) and "I saw smoke out of the exhaust while trying to start it"

Not sure if this helps but at least it gives a one stop reference point.

Besides, Pneese is obviously smarter than me, has logged off and is getting some rest.

I don't know about smart than you, but I have a busy next several weeks ahead of me, so the truck can't consume all my time. I appreciate all the help guys, but I need to do some testing before I can answer some of the questions. I did have a detail conversation with Turbine Doc last evening and he gave me quite a few ideas and after talking through it, it's very likely possible that I'm not experiencing the classic problems that you might expect. I also spoke to psychobilly last evening and he told me he had 4-5psi at the T Valve and that the other LP was good. After getting the truck, I think some routine maintenance was overlooked (for instance, I dont' think the injectors have ever been rebuilt). After putting everything together, here's my plan of attack....

1) change out LP with a known good one
2) change out injector nozzles with a new set of marine nozzles. I also have a pop tester, so I will pop test all the injectors and see if they have a good spray pattern before reinstalling. I ordered the marine nozzles last evening.
3) I just got a new battery, so I am going to install it.
4) bypass LP controls so it's always on with the key (at least for debugging)
5) check glow plugs and relay
6) try unplugging optical sensor since IP looks like it's never been off and may likely be bad
7) try advancing IP because we're very suspicious the problem I have is a dead stepper motor (it acts like it's retarded while cranking)

After doing this, we've eliminated the PMD, lift pump, fuel filter, optical sensor, glow plugs, and injectors.

psychobilly wasn't getting fuel to the injectors while cranking, but I know they're getting fuel after installing the new PMD because I've seen black smoke out of the exhaust while turning it over. It almost seems like it's getting fuel but at the wrong time which leads us to believe it's the stepper motor. Remember, even my friend said it rattles more than his '95 which would be a timing issue. One other thing, is even warm, in or out of gear, I have a high idle at about 1000RPM's which I'm sure is related to the problem.
 
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