My truck lost it's go and doesnt show any boost on the guage. For the last few weeks the turbo has been whistling alot more than normal and the other day it felt like the truck was doggin down and all the sudden a big poof and the road behind me was nothing but a black cloud. After that I got the check engine light. I have checked all the hoses and connections, can't find any leaks. The trouble codes are P2036 Turbo Boost Sensor A Circuit Range/Performance, and P2037 Turbo Boost Sensor A Circuit Low.

 

sounds like your boost/map sensor has gone bad my guess would be it is shorted to ground

 

From the black smoke and lack of power, I would guess you actually don't have any boost, as opposed to just a bad sensor. Do you have a gauge also, and if so does it also read no boost?

I think if it were mine, I would double check all the fittings (I've missed things the first time) then take a look at the turbo...

 

The boost guage reads up to maybe 5 pounds if i really push it but thats max. I disconnected the batteries to reset the mapp sensor on it and check the electrical connections and when I hooked it backup now I have up to about 15 pounds and no check engine light. It still kicks and bucks and has a lack of power, but way better. So it aint fixed I'm just trying to tie it all together for ideas. And now no smoke again just like before the problems, during these problems I was foggin up the roadway.

 

Hey - I had the low-power/check-engine-light problem last week and was able to resolve by replacing MAP sensor. Part from Cummins was under $50.00. See my posting/thread titled "p028 code." Good luck.

 

its one or the other -hole in sys./ map sensor/ turbo not turboeing

 

The first thing to check is the simple things. Check ALL your boots from the turbo to the engine. Look for one boot to have slipped off and also check the bottom ones for the possibility of having a hole in them. Sometimes they will swell enough to touch the inner fender and wear a hole through. If you need new boots, I would suggest that you call Piers and get the better ones from him. Did you have the computer scanned for codes? If you did what did you find? Once you are sure you don't have any boost leaks you can also check your turbo. If you can get the compressor wheel to touch the sides you will be looking for a new turbo. If you can't then the probability is the turbo is OK as long as it spins fairly freely by hand.
Let us know what you find
Tom

 

I'm gonna go through the truck this weekend and pull it apart piece by piece, but just in case it sparks any ideas here is an update. I can get up to 20 pounds of boost on this thing if I hammer it, but at cruising there is nothing showing on the guage and you don't even hear the turbo whistling. It just dies once your up to speed. When the boost is showin, the smoke is rollin. When you first takes off it spudders, for lack of a better word, for a few seconds before the turbo starts to spool. It almost seems like the turbo is hanging up or not turnin free.

 

I pulled it all apart today and didn't find anything lose and no holes. I am going to replace these little generic hose clamps with stainless steel ones. The turbo itself doesn't have any play in it, not touching anything and has just a little resistance on the spin, so i think it's fine. The truck runs decent just lacks some power and smokes alot more. Still looking for ideas. I tried to pull the map sensor today, in the instructions from this sight it says a 13/16 socket, but i have tried all the way to 1 1/8 and it still doesn't fit. Can anybody tell me what size they take so i can go buy a socket.

 

I'd pull the Comp box and see what happens.. Sounds to me like the timing is jumping around. Unplug that sucker and see if you can at least attain stock values.

 

what all wires have to be changed to disable the comp and get it back to stock.

 

I pulled the IAT Sensor, and there is no senor there, just a brass plug. The white piece shown in the picture is not there and from the looks of the brass hasn't been there in a long time. So now the question is where would it have ended up when it fell out, and what kind of damage would it do.

 

It would of gone threw the engine and out threw the turbo. You will want to see if there is damage to the turbo.

 

I would think that under pressure, the IAT would have blown out instead of being sucked in.

Is there anything hanging on the harness? I would think the electronic part would be just hanging on the plug.


As for the comp I thought you could just unplug the box from the pump. You shouldn't need to pull the tap wire.

J-eh

 

Was there a connection for the IAT, or just the brass plug?

Have you had the vehicle since day one?

If not, your IAT may have been relocated elsewhere.
Check near the air filter, some folks move them there to keep them cleaner,
especially those with exhaust brakes.

Comp doesn't plug into the IAT though, only the MAP sensor and data link, then the pump wire pierce.


IAT= Intake Air Temperature
MAP= Manifold Air Pressure (or Manifol Ambient Pressure)


phox