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1998 6.5 shuts off past 170° f

ak diesel driver said:
Sounds like a wiring issue. I'd get a new harness
Click to expand...

This harness?
quadstartuning.com

Engine Wiring Harness

Fits 1994-2002 6.5L N/A and Turbo Diesel engines with the side-mount turbo and the electronic DS4 injection pump. This is made to upgrade and replace the OEM harness that goes between the rear of the engine and the sensors/injection pump. This new wire harness will only mount ABOVE the intake...
quadstartuning.com quadstartuning.com
 
Cam and crank sensors both use 5v reference voltage. I would back probe the gray wire on the boost sensor and see if its losing 5v while it's acting up.. I see issues like that all the time on powerstrokes. The back pressure sensor shorts out and take the 5v ref down. Causes all sorts of weird problems. If its losing 5v ref unplug every 5v sensor and see if it comes back.
 
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Rockabillyrat said:
Cam and crank sensors both use 5v reference voltage. I would back probe the gray wire on the boost sensor and see if its losing 5v while it's acting up.. I see issues like that all the time on powerstrokes. The back pressure sensor shorts out and take the 5v ref down. Causes all sorts of weird problems. If its losing 5v ref unplug every 5v sensor and see if it comes back.
Click to expand...

While running I measured 5 volts on the boost sensor. I did measure around 2 volts on the IAT and ECT sensors. Truck ran to about 197 degrees and then died after I begin playing with the pedal I also tested the truck with all of the sensors unplugged and I still have the same outcome. The truck cranks at about 200 RPM when hot and will not start. the only thing I had plugged in was my optical sensor and my PMD.
 
Loganshaw_6 said:
While running I measured 5 volts on the boost sensor. I did measure around 2 volts on the IAT and ECT sensors. Truck ran to about 197 degrees and then died after I begin playing with the pedal I also tested the truck with all of the sensors unplugged and I still have the same outcome. The truck cranks at about 200 RPM when hot and will not start. the only thing I had plugged in was my optical sensor and my PMD.
Click to expand...
 
Well that's cranking plenty fast enough. Check to see if fuel is flowing out the T-Valve into a container while cranking it over. Probably take two people for observational purposes.
 
Bought a 1995 parts truck and used the harness out of it and I had the same problem. Would it make sense or is it even possible to swap the complete harness (PCM harness, grounds, fuse box, ECT) and PCM from the 1995 to my 1998? I'm not sure if it makes sense but I have the parts on hand. I have the ignition and key too. Today I did have help and found that it is spraying fuel while cranking with the t valve open after the truck stalls. Cracked injector 1 line and was getting fuel out too. After sitting for a few minutes after the truck stalls I did notice that the clear return line does have an air bubble in it. I traced the fuel lines for any types of leaks and found nothing wet. Is there a better way to check if it is sucking air in? There aren't any bubbles in the clear line while running but only after sitting. After it stalls I can give it the smallest spray of starting fluid and it'll fire over and run but it won't idle, rpm drops and truck stalls. Repeat that process with the ECT sensor unplugged and it'll idle around 800ish rpm. It's almost as if it's a high enough rpm that it will drop to about 650 rpm and it can pick back up once you let off the throttle. Is there any way to tell if I'm getting enough pressure through the injection pump once the truck stalls? Back to the question is it an electrical or mechanical problem? Here's a link to the t valve video I took. Sorry for the poor quality.

 

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Bubble is fine: We are looking for a constant stream of bubbles or going clear from no fuel.

I keep going back to post #41 and wonder how far you got on the time set procedure? Move the pump. Advance or retard it. Maybe you get lucky.

A video of it running may help as mechanical pumps are timed by ear anymore.

This is why you should put that new DS4 on Ebay and convert it to a DB2... :banghead:

1995 harness is a OBDI and your year is OBDII. Not going to be the same everywhere.
 
WarWagon said:
Bubble is fine: We are looking for a constant stream of bubbles or going clear from no fuel.

I keep going back to post #41 and wonder how far you got on the time set procedure? Move the pump. Advance or retard it. Maybe you get lucky.

A video of it running may help as mechanical pumps are timed by ear anymore.

This is why you should put that new DS4 on Ebay and convert it to a DB2... :banghead:

1995 harness is a OBDI and your year is OBDII. Not going to be the same everywhere.
Click to expand...
Today the truck ran to 182 °f ect with the lowest rpm being 692. Once we gave it throttle and let off it died. Tdc offset is at -0.25. Actual timing is around 4° while running at 1000rpm. How far should I advance or retard it?

As for a running video would you want it recorded when the truck is cold or up to temp? Do you want me to give it throttle and let it die or leave it?

I hate this ds4 and I borderline hate this truck at this point, I should have gone db2.

I didn't even think about the truck being obd 1 although I do have the entire parts truck. The engine is torn down and missing parts on it and the interior is trashed. Other than those two things I have everything.
 
Just the sound of it running and note cold or hot.

Off the top of my head that's way off.

Reference section how to:

FYI: TDCO - Timing the DS4 Injection Pump

DS4 Injection Pump The DS4-831-XXXX Diesel injection pump is a rotary Distributor-type Solenoid-activated 4 pumping-plunger 8 cylinder 0.31" plunger-diameter model - the four remaining digits denote Stanadyne final calibration specs - it is a constant-beginning variable-ending pump design with...
www.thetruckstop.us

@Turbine Doc describes setting it well here.

Understanding TDCO Learn/setting timing

One of my greatest weakness is understanding the timing of the 6.5. Years I've read about TDCO, advance, retard timing and I've never focused on it. So, in another thread in asking for help with starting, someone brought up timing. I read posts and threads about koko, time set, etc, etc...
www.thetruckstop.us
 
WarWagon said:
Just the sound of it running and note cold or hot.

Off the top of my head that's way off.

Reference section how to:

FYI: TDCO - Timing the DS4 Injection Pump

DS4 Injection Pump The DS4-831-XXXX Diesel injection pump is a rotary Distributor-type Solenoid-activated 4 pumping-plunger 8 cylinder 0.31" plunger-diameter model - the four remaining digits denote Stanadyne final calibration specs - it is a constant-beginning variable-ending pump design with...
www.thetruckstop.us

@Turbine Doc describes setting it well here.

Understanding TDCO Learn/setting timing

One of my greatest weakness is understanding the timing of the 6.5. Years I've read about TDCO, advance, retard timing and I've never focused on it. So, in another thread in asking for help with starting, someone brought up timing. I read posts and threads about koko, time set, etc, etc...
www.thetruckstop.us
Click to expand...
The more I read the more I think I have done something wrong or I missed something. So I'm going to explain what it did.

I installed the pump with the shut-off solenoid up and down. I did the Koko procedure and commanded the truck to do a relearn. At first my tdc offset was -1.94° so I advanced the pump. Did another Koko and got the tdc offset to -0.25°. commanded a relearn on my scanner and got the act timing to display 4°. At this point the truck is warm and has been shut off so it won't start or idle. Am I setting the act timing to 3.5 to obtain a tdco of -.75 to -.25 or am I setting the TDCO to -.75 to -.25 to obtain an act timing of 3.5? At what rpm and temperature should I have an average 3.5 act timing? Should the truck run on its own while commanding it to relearn? Mine dies. Am I doing something wrong? Do I need to move the pump again to advance or retard it? Maybe I'm over thinking it. Can you dumb down the process?
 
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When doing the KoKO timing relearn, my truck always dies. Fire it up and usually it continues on without dying again, runs rough until the job is near completed.
 

Here is the link to a video of it running while it is cold. I know the timing is not correct I have a TDC offset code currently. Unfortunately I don't have access to my scanner at the moment so I'm unable to verify where it is set at.
 
When it starts to run rough does it smoke alot out the exhaust?

I did a pump replacement on a 00 for a customer. I purposely set the timing off to see what it did when I commanded the TDCO relearn. With the TDCO over 3* it ran horrible, smoked and almost stalled. The actual timing was no where near the desired. I'm no DS4 expert but I think if you get the TDCO over 2.5* its may go into a fail safe. When initially moved the pump it ran normal until I commanded the TDCO relearn. Set it to .33* and it cleaned up as expected.
 
Loganshaw_6 said:

Here is the link to a video of it running while it is cold. I know the timing is not correct I have a TDC offset code currently. Unfortunately I don't have access to my scanner at the moment so I'm unable to verify where it is set at.
Click to expand...
I remember I had an issue trying to set mine (1999) and it would not set no matter what then I had found the wire from the computer to the boost solenoid was broken fixed it and it still was an issue until I plugged the boost solenoid back in...I was also running a mechanical gate...I have no idea whatsoever why this was but "it was."
 
Rockabillyrat said:
When it starts to run rough does it smoke alot out the exhaust?

I did a pump replacement on a 00 for a customer. I purposely set the timing off to see what it did when I commanded the TDCO relearn. With the TDCO over 3* it ran horrible, smoked and almost stalled. The actual timing was no where near the desired. I'm no DS4 expert but I think if you get the TDCO over 2.5* its may go into a fail safe. When initially moved the pump it ran normal until I commanded the TDCO relearn. Set it to .33* and it cleaned up as expected.
Click to expand...
When it starts to run rough it will surge and cut off not much smoke.
 
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