DTC 35 fault code

[DaddyB3089]

1995 6.5 Turbo Diesel Dually
260000 miles
Remote mounted PMD 6 ft. extention hard wired to wiring harness and mounted in cab of truck
Head gaskets replaced at 197000
Advance Auto OEM remanufactured PMD
Run 16 oz./tank of Walmart marine outboard oil

Now to the problem, truck is running fine but will skip or sputter if put under load at times. This does not always happen. It is throwing a DTC 35 code. Light will come on but will go out if I let off accelerator a little. My question is do you think I should change the timing on the pump a little. It is the green tag replacement pump and I really don't want to change it if I don't have to. The pump has not been moved since I have owned it (97000 miles) when bought. I am sure the gasket won't let go to make the timing adjustment, any suggestions?

[Kennedy]

In my experience in cab mounted PMD's lead a short life.

[DaddyB3089]

Will move it back to behind bumper then. Any comments on the other issues?

[racer55]

Add some lubrication to the fuel,these trucks were never meant to be run on ULSD.
Marine 0 ash 2 cycle oil at a ratio of 1:200 is good, a double dose to start when experiencing that code may help.

In winter a commercial fuel supplement with antigel and lubricity additive is a good move too.

The code is not timing related,but can also be thrown when a PMD is failing.

[Robyn]

As mentioned, the 35 is likely related to the PMD about ready to take a dive.

Also, get the PMD on a large heat sink with lots of fin area that will transfer and throw off the heat.

Be sure to use heat sink paste (looks like white grease) between the PMD and the sink. You can get this at most computer parts suppliers.

Lots of cool air is the answer.

My experience with the various PMD'S is that the D TECH is a pretty good one.

There are no perfect answers to the problems with the DS4 injection system, as this system was flawed from the gitgo.

The 2 stroke oil is, as mentioned, a great idea too.

Another great plan is to toss the factory fuel manager and install a 2 micron Racor filter up near the ABS unit and just extend the fuel lines.

The factory filter is too coarse and allows too much dirt through.

The fuel solenoid in the IP that controls the actual fuel metering is moving at a very high rate, so that it keeps fuel delivery perfectly matched to what the ECM calls for. This fact along with any dirt, can and does lead to wear of the parts and RESPONSE TIME anomalies (35 or 36 codes)

The ECM sends constant signals to the solenoid and expects a return signal within a specified time frame and this signal tells the ECM that the required task was completed. A short or long response time will trip a code (SES LIGHT )

A failing PMD can also cause these codes to trip, although fairly rare, it can happen. Generally the first you know of a PMD issue is when the engine dies. :eek:


Good luck

Missy

[DaddyB3089]

Thanks for all of the input. As mentioned I am already running the oil in every tank and have the PMD on the large blue heat sink. It was mounted in the cab but have relocated it to behind the front bumper. The Pmd was throwing this code so I have changed it and replaced with a new one. I still get the code but no dead runs yet. Thanks for the explanation about short signal. I guess that answers my next question of if this could be caused by the sock in the tank being the problem. Sounds like not.

[racer55]

If fuel lube and a new PMD don't cure the problem a quality IP is the most likely cause of the code.

Make sure the IP harness ground is clean and secure on the top of the IP and/or drivers side battery ground ONLY.

[Kennedy]

Thanks for all of the input. As mentioned I am already running the oil in every tank and have the PMD on the large blue heat sink. It was mounted in the cab but have relocated it to behind the front bumper. The Pmd was throwing this code so I have changed it and replaced with a new one. I still get the code but no dead runs yet. Thanks for the explanation about short signal. I guess that answers my next question of if this could be caused by the sock in the tank being the problem. Sounds like not.

Do you have pics of this heat sink?

The only blue one that I have ever seen I would categorize as far too small. Maybe evey teeny.

This is a large heat sink:

http://www.kennedydiesel.com/6265FSD.cfm

[moondoggie]

Good Day

Good ideas, all.

"...will skip or sputter if put under load at times." Make sure you test your lift pump for both flow rate & pressure. I had one lie to me. I opened the drain valve & got lots of flow. It still wasn't good enough, at least for the IP in my truck, because it didn't make enough pressure. Some IPs will work fine with a dead lift pump, others will work poorly. Weak lift pump output, either flow or pressure, can produce this symptom.

"...DTC 35 code. Light will come on but will go out if I let off accelerator a little." Boy, does this sound like a problem I had with my 95 pickup once. In my case, however, the truck ran perfectly, it just had the DTC 35, which disallowed the cruise control from working. Long story short: Refurb every ground you can find. Everything else I tried to get rid of my DTC 35 failed; fixing the grounds eliminated the DTC 35, & it never came back in the remaining years I had the truck.

Good Luck & Blessings!

[MikaN]

Good Day

"...DTC 35 code. Light will come on but will go out if I let off accelerator a little." Boy, does this sound like a problem I had with my 95 pickup once. In my case, however, the truck ran perfectly, it just had the DTC 35, which disallowed the cruise control from working. Long story short: Refurb every ground you can find. Everything else I tried to get rid of my DTC 35 failed; fixing the grounds eliminated the DTC 35, & it never came back in the remaining years I had the truck.

Good Luck & Blessings!

Seems that I have similar issue. When the engine rpm is over 1500 for 2 seconds the engine light will go ON and after the rpm is lower than 1500 for 2s, the light will go OFF. It does not matter of the load, the same can be seen on P and all gears. And there is code 35, when reading the codes.

Could the optical sensor and fuel solenoid be removed and cleaned somehow?

[racer55]

The OS can be removed and cleaned but must be done carefully:
http://www.mamut.net/royh/newsdet9.htm

The fuel solenoid is not user serviceable to my knowledge.