Help with a P0236 Code

[aj neireiter]

I know that the code is P0236 and it has to do with the turbo boost sensor A circuit range/perforfance, that doesn't tell me a whole lot. Any help on this subject would greatly be apperciated. THANK YOU. I have a 1998 1 ton dually 2wd 6.5td.

[charliepeterson]

It sounds like you may have a "cranky" waste gate solenoid. Heat is a big killer of this thing. Another helpfull tool is a scanner or boost pressure guage while your driving with your right foot to the floor.

You may have set this code one day while driving up a hill or pulling a load which required more boost than the engine was giving for the large amount of fuel that was being dumped into the eight holes.

Try looking out the right side window for black smoke before and after the SES light comes on. A little gray is good, that's power!!

[aj neireiter]

I took your advice, and watched my right side mirror.There was black smoke. I had the waste gate solenid about 9 months ago.I'll pick up a new one, You say heat is hard on them, where is a good spot to move it to? thanks again.

[DennisG01]

I had the same code about 3 months ago. After a few non-incident starts it went away, though. I thought that it might have been a vacuum line that was loose and then the shaking of the engine during starting tightened it back up. Sound reasonable - or am I stretching it?

CHARLIE PETERSON (or anyone else): you mentioned about black smoke at full throttle...I get it at about 3/4 throttle and up, with a lot at full throttle. I'm new to diesels, but I thought that that was normal. If not, does that mean the wastegate isn't doing its' job? Is there anything else it could be? Would one of those Heath Turbo Master's fix the problem?

[charliepeterson]

Dennis

"Would one of those Heath Turbo Master's fix the problem?"


It cured mine.

The vacuum pump should pull 20"hg at the waste gate solenoid and slightly more maybe at the pump itself.

The ECM modulates the ground circut to the waste gate solenoid to controll the boost the engine makes. Vacuum is the other half of the equation.

Something went crazy in my ECM and I lost this circut. I found out if you ground the ground side of the solenoid you will get "CRAZY" boost! My boost guage only goes to 15lbs and I spiked it very easily along with the pyrometer. I gave up for now chasing the circut and went with the Heath Turbo Max setup.

Even at WOT the smoke really should be only gray and not really too heavy, seen in the head lights.

[DennisG01]

Thanks for the info, Charlie! When I stomp on the peddle, I get a short burst/cloud of black smoke and then it turns into the grey smoke you mentioned (along with less smoke altogether). Is that ok?

[charliepeterson]

We don't have any kind of throttle delay on our trucks. From a dead stop when you mash the pedal the injection pump goes to full fuel. It takes a minute for the turbo to catch up with the fuel delivery, this is where the black smoke comes from.
The correct way to drive is to slowly roll into the accelerator so the turbo can keep up with the fuel.
That's not how I drive though!

[DennisG01]

Thanks again, Charlie - that makes sense. I guess my wastegate is working right now, but I think I still want to get the Heath TM - but first I need to get an exhaust and gauges. I wish I had $5,000 that I could blow on the truck - with the help of the internet I could spend it in about 8 minutes!

PS: I don't normally drive like that, but I do enjoy the occassional tailgater that I can give a nice big blast of diesel smoke to!