Hey everyone, new to the forums. I've already done some research by looking around at different threads on this particular problem and it seems that my problem is more than likely in the PMD. I did have a question though, I ran the diagnostic on my truck and its giving me a code of P0236.
A friend of mine had mentioned that it could possibly be the map sensor making things go haywire as they are but then again he is mostly a Ford guy.

So here is whats going on;
Truck intermittently stalls either when at idle, slowing to a stop, or just going down the road at 55-65 mph. No electrical problems just cuts out and powering steering goes, brakes don't work all that great, and sometimes it starts right back up or takes a few minutes to restart. Now I know these all seem to be signs of the PMD sensor, but the Diagnostic Code is what was throwing me off

By the way my truck is a 98 Chevy 2500. 6.5l TD. Injection Pump was changed 2-2 1/2 years ago with the PMD changed at about 1-1 1/2 years ago. (First time this has personally happened to me, I didn't own the truck when the pump and pmd were originally replaced)
Also I'm not sure as to what designation the VIN number is as I've seen people mention the "f" VIN but mine actually starts with 1GC. So any help would be appreciated as I'm planning to start taking the manifold off today to take out the IP.

Also, one more thing when you first turn the key over im getting not only the usual wait to start light, and the service engine soon light but im also getting a check gauges light but that turns off once the truck turns over. All gauges seem to be at normal operating ranges. Battery seems to be always on or around 14v, oil pressure right around 40, temp after running never really exceeds 180-190. Fuel gauge, tach, and speedo all work fine.

P0236 is turbo boost pressure sensor out of range. Vac pump could be dead, could be a cracked or broken vacuum line, could be a dead wastegate solenoid, or a few other things. The most common problem is the vacuum pump being dead.

It is a 98 so it is probably the Turbo Solenoid that caused the P0236.
The P0236 won't caused any stalling.

So you may have a PMD issue.

DO the diagnostic checklist last item from the "STICKY:" section.

8th digit would tell you if you have an F or S engine. Ed

Where is the turbo solonoid. I have the same problem

thanx
Joe



It is a 98 so it is probably the Turbo Solenoid that caused the P0236.
The P0236 won't caused any stalling.

So you may have a PMD issue.

DO the diagnostic checklist last item from the "STICKY:" section.

Where is the turbo solonoid. I have the same problem

thanx
Joe


The turbo solenoid is the wastegate solenoid which in your signature says is new. If you still have the same problem then bosot is either too high or too low, likely too low or zero. Weak/dead vacuum pump and or cracked/broken lines are next suspect. Then a leaky wastegate actuator. If its the latter, plan on getting a boost gauge and turbo master, it will be ALOT cheaper than getting a new actuator.

It "could" be the pmd.

If you experience any hesitation on acceleration I would check your lift pump operation :) And I take it that the stalling is pretty much random?

Yeah the stalling is random.
I just finished putting the new pdm sensor in, havent got the manifold back on yet so I guess we'll go from there.
Although I know there's still something wrong with the turbo. Feels like theres no boost on accelaration, either way since i got it down going to give it a run through so if maybe the turbo is locked up or something.
Thanks for all the help guys.

If you aren't building any boost and your truck is still equipped with the vacuum actuator then I would say you should check for proper vacuum. You can check at the pump, then at the solenoid (should be drivers side along intake) and you can check at the actuator also.

If the turbo is actually bad, I am sure that it wouldn't sound to well...

I hope that PMD solves your stalling problem, if not come back and I'm sure someone will have a solution or more help on finding the problem.



Then a leaky wastegate actuator. If its the latter, plan on getting a boost gauge and turbo master, it will be ALOT cheaper than getting a new actuator.

I totally agree lol. I called a local dealer on an actuator and he said something like $300?!? Turbo Master is $100 or you can make one for like 10 or 20 (search for help on that).

The vacuum pump seems good though I have found & replaced one line. (Cracked line at the WG actuator.) The actuator seems to be good as well.
Turbomaster & boost guage here I come. Now to get the dollars:(
Thanx
Joe

The turbo solenoid is the wastegate solenoid which in your signature says is new. If you still have the same problem then bosot is either too high or too low, likely too low or zero. Weak/dead vacuum pump and or cracked/broken lines are next suspect. Then a leaky wastegate actuator. If its the latter, plan on getting a boost gauge and turbo master, it will be ALOT cheaper than getting a new actuator.

Yeah the stalling is random.
I just finished putting the new pdm sensor in, havent got the manifold back on yet so I guess we'll go from there.
Although I know there's still something wrong with the turbo. Feels like theres no boost on accelaration, either way since i got it down going to give it a run through so if maybe the turbo is locked up or something.
Thanks for all the help guys.

May want to move your PMD to outside the engine compartment on a heatsink with extension cable. Otherwise, it will be bad again by next spring.

May want to move your PMD to outside the engine compartment on a heatsink with extension cable. Otherwise, it will be bad again by next spring.

yes deffinetly....before i found this site, i had the pump driver replaced twice on my 94. once i stumbled onto this site and saw that the pmd is the problem, i moved it with the heath unit and hasnt caused any trouble since. saved a ton of cash too now that i know what the "real" problem was. like was said before, if you just replaced on the original location on the driver pump, then you will be doing it again with in a year. take the advice and move that thing with a relocation kit out of the engine bay. the eletronics arent happy with the heat when there is no fuel flowing through the pump after shut off.

blakestiff (http://www.dieselplace.com/forum/member.php?u=90579) do your self a big Favor, purchase the boost and EGT guages before you go to the turbo master wastgate control. I popped both heads on my rig, it cost me the block and heads, not cheap

blakestiff (http://www.dieselplace.com/forum/member.php?u=90579) do your self a big Favor, purchase the boost and EGT guages before you go to the turbo master wastgate control. I popped both heads on my rig, it cost me the block and heads, not cheap

TinBender, did you build your own TurboMaster?

The reason I ask is that if it was a genuine TurboMaster, setting it according to directions will give you boost well within allowable limits.

That's the advantage of buying rather than building... the engineering performance and specs are consistent and known.

TinBender, did you build your own TurboMaster?

The reason I ask is that if it was a genuine TurboMaster, setting it according to directions will give you boost well within allowable limits.

That's the advantage of buying rather than building... the engineering performance and specs are consistent and known.

agreed, bill heath personally installed my (his) heaths t/m. he set it and when we went for a drive the boost gauge said AOK. i have never changed it from his initial setting. Ed

well as bad as i hate to admit it, it is a Turbomaster, please don't ask me any more because " I R STUPID " Ok confession completed:D:D

Its been a couple months since i've posted anything on this but finally got everything figured out.
PMD sensor was bad, didn't have the time go out and get the remote mount kit, needed the truck back asap, so maybe soon i'll spend the money to get the kit to move the PMD. Changed fuel filter too right around the time I changed the driver so the thing runs great

As for the turbo problem not working, figured out what that was.... completely by accident. So you know, since its November now theres really no need for the a/c anymore. Turned off the a/c ran it around town for the day started noticing power I didnt have before. Check engine light turned off and everything is perfectly fine, turbo works great now. Apparenlty, as far as I can tell, one of the vacuum lines going to or from the a/c is cracked and is leaking so I imagine thats where all my turbo problems all.

Anyways, I really appreciated all the help guys, couldn't have gotten as far as I did without all your knowledge and helpful input! THANK YOU ALL!

As for the turbo problem not working, figured out what that was.... completely by accident. So you know, since its November now theres really no need for the a/c anymore. Turned off the a/c ran it around town for the day started noticing power I didnt have before. Check engine light turned off and everything is perfectly fine, turbo works great now. Apparenlty, as far as I can tell, one of the vacuum lines going to or from the a/c is cracked and is leaking so I imagine thats where all my turbo problems all.

There are no vacuum lines going to or from the AC.

Well, correct me if im wrong but I always believed that the a/c system carried its own vacuum lines. Now I realize these lines do not connect to the turbo itself, but isn't everything basically inter-related in some way? So wouldn't a crack in the vacuum lines on the a/c pull vacuum out of the system not allowing the wastegate to function normally? Or am I just talking out of my ass and not making any sense? Either way I dont know, it works without the a/c on but it doesnt work when it is on. So something is definitely affecting the other.

Well, correct me if im wrong

OK - You're wrong... I think -- Since I have no idea what kind of truck you have.
On the 6.5 there is a vacuum pump driven by the crank via the belt. It supplies vacuum for the turbo charger wastegate controls and the EGR controls, if the engine has an EGR. That's it. Doesn't even tie into the cab for vent control or any other system on the vehicle.
Take a minute and fill out your signature (http://www.dieselplace.com/forum/profile.php?do=editsignature) if you would.
Put a vacuum gauge on at the wastegate and see if turning the A/C on causes it to drop. I can't visualize how the vacuum pump could be affected, but anything's possible. Bad belt?? Maybe?