Can the fuel termperature sensor be sourced without buying the entire injection pump? Here's my issue: PCM is throwing codes 17, 18, and 35. I've pulled the intake manifold to get good access to the IP and went through the tests in the manual. Everything checked through on Code 17, leading to faulty PCM connection or bad PCM (yikes!). Code 18 points towards a potential faulty sensor, as the reading for the sensor line (pink) does not go to 0.4-0.5 volts when engine is cranked and shut off. Have not gotten to address Code 35 yet, which sounds like a potential PDM problem.

So, back to the question, can the sensor be purchased anywhere independently? Or maybe there is another solution I'm not thinking of. Greatly appreciate any advice, as not happy about throwing a whole bunch of cash on a new IP if it can be avoided.

Should have added into the post that the truck runs fine. Possible filter harness? This is my first deisel, so running fine is very subjective. I've seen some linkage to cruise control and PDM, cruise does not work but I have not dug into that very deep.

Remove the OS FIlter, run direct-connected, see how that does - cruise don't work because of the DTC's

Welcome to the wonderful world of the DS-4 and related stuff...

First - 17,18,35 definitely codes that can signal a bad PMD. CAN, not DO. Just don't rule that out, yet. The codes are killing your CC, so ignore that for now.

I have seen all three of these codes with ULSD issues ... are you using any fuel treatment? We have collectively seen these codes just 'disappear' after a tank of 2 of fuel with lots of extra lubricative additives (ie... 8 oz PowerService Silver and 8oz 2-stroke oil added per fill-upfor a few tanks, then drop to 4 oz of each per tank)

Unfortunately, these codes can also indicate a failing IP. In most cases, they don't... if the IP is failing, you get other symptoms, as well as these codes... you seldom get these alone with a failing IP.

Summary: I'm Cheap. If the truck is running OK, I start with the cheap stuff and work my way up. Run a few tanks of additives through her, keep clearing the codes and see if they come back (you can test yours with a paperclip, if you don't have a code reader). Filter harness shouldn't cause these codes, but it's cheap, too. I'd remove it and see what happens, rather than buying a new one, just yet.

Try that - get back to us.

Ummmmm...............OS Filter will cause 17, 18, 35 - and any fault consistent with OS failure - VCC supply for the OS feeds thru the filter, as do all the signals back to PCM

Faulty wiring\harness\connections do result in exact symptoms as faulty module\device, so that is first area of concern, then onto the devices - simply unplugging\re-plugging related connectors often 'heals' the fault, which is then blamed on the replaced module\device

LOL ... what he said.

The problem with codes that can be caused by a number of things is figuring out which thing to fix first. Dealers fix the most expensive one first. We operate on the other end... wait, that didn't sound good...

You get what we mean...

No fuel treatment, but I've only burned one tank through it in the six weeks of ownership. Question about pulling the filter for the codes to go away... referenced "optical fuel sensor" on our forum here, and based on other threads, the filter is intended to minimize interference from the alternator. Am I misunderstanding?

Also, is there a way to connect/disconnect the lines to the OS without pulling the manifold? I've got it off now, but shudder at the thought of reinstalling the whole setup just to pull it back off after the trial. Any thoughts?

No fuel treatment, but I've only burned one tank through it in the six weeks of ownership.

Question about pulling the filter for the codes to go away... referenced "optical fuel sensor" on our forum here, and based on other threads, the filter is intended to minimize interference from the alternator. Am I misunderstanding?

Nope, you got it right. It is basically a resistor pack with a 4-prong plug on both ends. Take it out and just connect the ends together to bypass it... the truck wil run just fine without it, but you SHOULD replace it, if it turns out to be the culprit.


Also, is there a way to connect/disconnect the lines to the OS without pulling the manifold? I've got it off now, but shudder at the thought of reinstalling the whole setup just to pull it back off after the trial. Any thoughts?

Just pull them apart, make sure they're clean and contacting, and put 'em back together. Do it a few times to make sure they're connecting. With a lot of these connectors, they only touch on a few surfaces and the rest oxidizes... when the contact surfaces fail, then there is very sparse contact left... manipulating the connector is somethimes all you need to do.

No fuel treatment, but I've only burned one tank through it in the six weeks of ownership.

Get a fairly heavy dose into her now... like I said, at least 8 oz of each, maybe as much as 12-16. Add a full tank of fuel.

The stuff burns and won't hurt anything... if nothing else, you'll get more power and fuel mileage.

It appears (from us experimenting) that 4 oz of each is optimum as a cost/benefit thing... fuel savings more than pays for the additive.

Latest and greatest... Pulled the harness and backprobed the connector leading to the PCM (which I am taking to mean stick a probe on the back end of the "connected" connector). Still got low readings on the hi-res and cam signal test:

Hi-res: between 2-3 volts after cranking, I got 1.18v
Cam Signal: between 0.4-0.5 volts after cranking, I got a whopping 0.08v

Before taking the manifold off, the truck ran without stumbling, unusual shutoff, etc. Maybe the best bet is to put it back together, put in the additive and see what happens.

By the way, what is USDL?

I think you mean ULSD and it stands for Ultra Low Sulfur Diesel. I am sorry if this was not what you are looking for and some of the other guys here will even help me out then and let me know.

Ryan

Thanks, that rings a bell. Living in Georgia, we're probably still on a high sulfur diet. I love the South!

Those voltage readings are prolly correct as the output is digital pulses while cranking -

the low res would have higher voltage because of lower frequency - 4pulses per crank revolution

the hi-res would have ower voltage because of higher frequency - 64pulses per each low-res pulse, for 256pulses per crank revolution

end voltage would depend on whether the encoder disk stopped on a slot or between slots

Disconnect both batteries during the time when you are cleaning off the intake area and temporarily replacing the intake manifold and hooking up the IAT and MAP sensor wiring - that should clear any codes.

Reconnect both batteries and try starting the engine with the OS Filter removed and the OS direct-connected to the engine harness, see what transpires - if you successfuly cleaned the area, the engine will run just fine with the intake manifold laid into place, unbolted

Truck is up an running again with the OS Filter in place. Filled up the tank with the powerdiesel additive (16oz) recommended earlier. Want to confirm the 2-cycle oil before adding as well... Same oil I put in lawn equipment and boat, or is it a special derivative?

Its ULSD, not USDL. It stands for Ultra Low Sulphur Diesel. Its the new industry standard to help reduce emmissions. Only problem is that most "older" diesels use sulphur to lubricate the pump and injector seals. Take the sulphur away, and it causes all kinds of problems. You should use some kind of additive, IMO.
Ryan

yes, its the same 2 cycle oil you would put in a boat or 2 stroke lawn mower

Just make sure it is ashless, and TC3 is best - wallyworld carries a gallon of Valvoline TC3 Syn for ~8bucks - use less syn than dino for the same lubricity