Help, Stranded. No restart. DTC P0335

[Big T]

Drove the '99 around today completing errands. Numerous shut downs and restarts with no problems, even full coolant temp. So decided to take the truck up to Big Bear (100 miles one way). Engine throws a code P0335 on the way up. We stopped at a market in town for food and truck will not restart. Same as last week, except now the code. Tried a good spare PMD and nothing.

Last week it did the same but in my yard. Left for a week on business came back and it started up just fine all day until we go to to Big Bear.

What does this P0335 crankshaft position sensor A circuit mean?

 

[Big T]

I was able to get it started. PMD has nothing to do with it. It's a fuel delivery issue. Cranked the engine with valve open on top of the FFM and no fuel came out. Finally pulled the filter and cranked the engine. Can hear he lift pump going. Put it back together and it started. Drove it back to our Big Bear Lake home and shut it down for the night.

 

[Will L.]

Dude! You got my number, Use it next time.

Your new homework assignment is a fuel pressure gauge- which would have told you the issue.

The confusion is that the Ip couldn't pull through the Lp. Filter plugging or a finer filter than stock? Maybe Lp not aowing flow through on fail from restriction. Something else is going on there besides just a non working Lp.

 

[Big T]

Dude! You got my number, Use it next time.

Your new homework assignment is a fuel pressure gauge- which would have told you the issue.

The confusion is that the Ip couldn't pull through the Lp. Filter plugging or a finer filter than stock? Maybe Lp not aowing flow through on fail from restriction. Something else is going on there besides just a non working Lp.

What about P0335 code?

 

[deejaaa]

P0335 DTC is set once PCM fails to detect proper sensor operation from crankshaft position sensor. This causes Check Engine Light to be displayed and failsafe mode.
P0335 can have a variety of causes:

• Open or short in wiring harness
• Poor electrical connections
• Crankshaft position sensor failure
• Damaged signal plate
• Broken timing belt or chain
• PCM faulty
• Engine timing belt or chain fixed along with any mechanical damage from this
• Additional comments regarding P0335 code
  CPS is used to monitor how fast crankshaft is spinning. Computer reads this in RPM’s. PCM uses CPS and camshaft position sensor to vary fuel mapping and timing.
  From a Google search............

 

[Will L.]

If no other codes are present, we used to check wiring for chaffing/ grounding, if ok then we just swapped the sensor.
When the cps or optic sensor is bad it makes for really harder starting. So, maybe you had no fuel because of lack of signal from cps.

 

[1994ch]

Still sounds like you have a lift pump/fuel delivery problem as well, if you don't have fuel pressure at the drain valve while cranking....

 

[Big T]

If no other codes are present, we used to check wiring for chaffing/ grounding, if ok then we just swapped the sensor.
When the cps or optic sensor is bad it makes for really harder starting. So, maybe you had no fuel because of lack of signal from cps.

I'm thinking the hard starting is due to this CPS code. IP is new, so I'm assuming optic sensor is fine.

I just traced down the harness for the CPS. It's intact at the CPS, all three wires. I did not pull the CPS. The harness comes up the front DS of engine, goes across at the back of the IP where the top 12 point nut is, then bends and dives into the valley. I know that while doing the work on the IP and manifold, I had to move that one A LOT. Not sure where it ends up once it's in the valley. Also not sure how to test the harness.

Other things I saw:

1) last remaining oil leak looks to be the damn oil filter bracket (4wd) which is wet. From valve cover down to Filter bracket is clean and dry.

2) braze weld on pyrometer broke and the pyrometer blew out, explaining the non-working egt gauge and interesting sound.

 

[1994ch]

So are you getting fuel out the drain valve now?

 

[Big T]

Went through the crank position sensor harness this AM and just ordered new harness repair plus CPS and the oil filter seals.

Hard starting again. Opened bleeder on top of FFM and the lift pump pushed out a heavy flow. Closed it up and it started. Pretty certain it's the CPS or it's harness.

I'm finishing up clearing a lot here today and have just left the truck running. I will be able to make it back down.

 

[schiker]

I can't remember is it the optic sensor or the crank position sensor if you unplug it it will default to limp mode and crank up to a default timing and fuel map?

Could unplugging one or both (which one) be used to help diagnose it or when on side of road get it going by forcing the ECM to crank at default settings?

I thought the later years did reference the crank position sensor and ecm opened power to the LP circuit then went through the OPS as secondary system. If you long cranked w/o running it might have timed out the LP circuit?????

 

[Big T]

We're going to head down today. I called Will and went through this. Pretty certain the hard starting is due to the CPS and/or it's harness. I've ordered a replacement CPS and repair harness. I didn't note which harness exactly, but there was one that connected by PS of the IP which had a broken tab lock on the male side. I'll pull the manifold again (getting good at this) and go through it.

Just need to get it started and I'll be able to make it down.

 

[WarWagon]

Jumper the lift pump on by removing it's relay and jumping the plug. At least you will keep the lift pump on. My 1995 never pulled through a dead lift pump and that may have been a collapsing hose that later kinked completely off.

 

[Jaryd]

It might be a good idea to put the wiring harness that runs under the intake on top of the intake. After having to pull my intakes a couple times for different things it made it easier to plug and unplug everything. I put mine on top and it runs down the passenger side of the lower. Unplug it, lay it out of the way and I have no wires to work around when I'm down in there un bolting everything.

 

[ak diesel driver]

Sorry forgot to reply earlier I got sidetracked. Yes unplug the optical sensor to test the CPS. Then start it, it will take quite a bit of cranking to start it and it will be in limp mode. And yes it works opposite for testing the OS.

 

[Big T]

I am certain my issue is the CPS or it's harness. It starts, but it takes extra long. Just when you think you should stop cranking, continue cranking and eventually it lights.

I made it home. Parts are ordered.

 

[Will L.]

Sorry forgot to reply earlier I got sidetracked. Yes unplug the optical sensor to test the CPS. Then start it, it will take quite a bit of cranking to start it and it will be in limp mode. And yes it works opposite for testing the OS.

Yeah, he has the 335 code and it WILL NOT clear. So really thinking disconnected or shorting in the harness on the cps circuit.

If you undo the optic and it wont start at all- that will confirm it dead cps circuit.

Oh, you silly ds4 guys

Well, is what it is.

If the runaway pmd would be cured I would probably go for another ds equipped truck. But not holding my breath. On the run away pmd- Les, I have a Hummer owner that has one. When we meet up later this year I will grab it and send it up for your testing you want to do.

Enjoy that cozy Cali weather, BigT. I'm sweating while typing taking a break from installing new back doors on my house. 105 with 19% humidity at 7:00 at night. Phone got so hot in my pocket I lost service for a few hours today. Haha.

 

[ak diesel driver]

You know Will there is a new digital PMD out now.

 

[Big T]

Pics of the lot clean up. This is across the street from, midway up Bear Mountain Ski Lift.

 

[Big T]

Yeah, he has the 335 code and it WILL NOT clear. So really thinking disconnected or shorting in the harness on the cps circuit.

If you undo the optic and it wont start at all- that will confirm it dead cps circuit.

Oh, you silly ds4 guys

Well, is what it is.

If the runaway pmd would be cured I would probably go for another ds equipped truck. But not holding my breath. On the run away pmd- Les, I have a Hummer owner that has one. When we meet up later this year I will grab it and send it up for your testing you want to do.

Enjoy that cozy Cali weather, BigT. I'm sweating while typing taking a break from installing new back doors on my house. 105 with 19% humidity at 7:00 at night. Phone got so hot in my pocket I lost service for a few hours today. Haha.

Wish I was still up at Big Bear.
Today high 74 F and low of 48 F with thunderstorms in the forecast. I love that kind of weather.

I have another friend who lives in Henderson NV. He's a maintenance diver
on the Bellagio fountain pool. Said the water temp is 84 F and air temp is 105 F. That's like East Cape Baja this time of year.

Back at work. Downtown LA in air conditioned building. Riding air conditioned train into work. Next week in SF followed by two weeks of fly fishing with April and the dogs.