2012 Kenworth Paccar MX-13 Turbo issues

If anybody can give any suggestion as to what could be wrong with my truck it would be much appreciated.

I just got loaded and was merging onto I-95 North in Baltimore, Md. I heard a leak start somewhere and I lost all boost immediately afterwards. The turbo was not spooling at all. I limped the truck into the T/A and looked for the leak. I found that the rear gasket on the DPF was blown and there was exhaust leaking at that point. I took the truck into the shop and had both gaskets and both clamps on the DPF replaced but the truck is still not making any boost.

The codes I saw on my bully dog were as follows: (I apologize I don't have the actual code numbers, as the bully dog is with the truck in baltimore and I am home at this point.)

1. Engine brake switch in wrong position
2. Low voltage on ECM pin 49
3. Turbo speed malfunction high (this code is not showing any more)

I had the truck towed to Middleton and Meads in baltimore so they could figure out what needed fixed. On Friday they told me they suspected the boost pressure sensor and that they would have the new one monday morning and get it replaced. Today they said they replaced it and the truck is now running better but not at 100%. They also said that the turbo was spooling up now.

I drove my happy butt to baltimore today only to find that the truck's condition is exactly the same. No boost, turbo not spooling.

My theory is that the shaft inside the turbo snapped and the exducer and inducer are not connected anymore, so it is not making any boost, but also not throwing any turbo related codes.

The shop is taking the exhaust off of the back side of turbo in the morning to see if the two halves of the turbo are still connected.

Any suggestions or advice would be appreciated at this point.

 

If the shaft in the turbo snapped there would be lots of smoke

 

Is it possible the shaft snapped, but no oil leaked to cause smoking? It is not smoking, no codes other than the ones I already mentioned. Could fuel delivery be at fault? I am just trying to figure this out.....

 

Probably something in the turbo itself. Those use the Holset VGT… if it were the VGT system, there’d be a DTC for that (or more).

I don’t have access to MX-13 shop manuals anymore, so I can’t tell you what circuit pin 49 is.

 

Been doing some online research, do you think a faulty turbo speed sensor could cause the turbo not to spool?

Also could a problem with the jakes mean no boost pressure?

 

Also, what is a DTC?

 

Nevermind, figured it out.... just fault codes

 

Check all fault codes first. If boost sensor was soot packed, rest of air management sensors need checked. On EPA10 motors, the sensing tube to exhaust gas pressure sensor before turbine tends to plug. Also check EGR Delta P sensor, tubes, and Venturi for plugging. If turbo shaft snapped you would know it... Not a quiet experience.

 

They changed the fuel filter out this morning, checked the exhaust side of the turbo and said that its fine. They are going to check turbo speed sensor and the humidity sensor in the intake next. Anybody think of anything else?

 

Update, the engine is giving two codes:

P2544 CAN communication - Message (PROPB_VIC) data error, Engine brake switch from vehicle control system

P0079 BPV position - Voltage too low or short circuit to ground

The shop is looking into the Back Pressure Valve tonight. Could this cause the engine to have 0 boost pressure?