Duramax Turbo adventure conclusion

Lwiddis wrote:
"The dealers refused to work on it without seeing the code for themselves."

Probably due to the manufacturer's rules.

I had pictures of the message but the code itself would disappear before I could get to a dealer. So all that it was doing was annoying the heck out of me.

When the CEL turned on, did you ever check to see what code was set? (Pxxxx) ?

Grit Dog - I’m not going to bad mouth the garage that replaced the turbo (though wish we had tried the MAP sensor first) because I got that same advice from 3 dealership garages that looked at it over the couple years I was dealing with it. Sporatic problems are tough, especially when needing significant load to elicit. The good news here is that garage saved me significant $$$ from what the dealership garages quoted.

Since you’re in WA I will tell you that the guys that replaced the MAP sensor (directed solution from me after discussing it with my home garage) was H & H Diesel Repair in Fife, WA. I didn’t give them a real chance to diagnose etc because we were traveling and they were working me in to a full schedule. I can tell you they seemed to know what they were doing, worked with me to squeeze my repair in and tested it as best they could without dragging my 5er around. They concluded the new MAP sensor behaves a little different from the one they replaced. Couldn’t confirm that difference was related to my issue but made a good case it might be. Bottom line, I would go there again if in the area.

"The dealers refused to work on it without seeing the code for themselves."

Probably due to the manufacturer's rules.

Glad that you got if fixed. It really is appalling to me that vehicles don't come with good on-board diagnostics and meaningful error messages.

I used to work with CNC machines. One brand had excellent error messages that you could generally take to the bank as to what the problem was and that was over 30 years ago. We had another brand (German made) that generally displayed error messages that were totally irrelevant. Trouble shooting was a nightmare. Guess which brand I only bought one of. Unfortunately in vehicles it seems like they are all equally bad.

I can sympathize with your problem. I recently had a problem with my truck that only revealed itself under heavy loads. You generally don't want to take a 16,000lb trailer with you to the mechanic but then the mechanic can't re-create the problem. I had another issue where the code would appear randomly but would clear itself before I could get to a dealer. The dealers refused to work on it without seeing the code for themselves. Both situations clearly call for better on-board diagnostics and that burden shouldn't be on the customer.

Post the name of the shop so we know who didn’t rip you off for another turbo, please.

When I was doing maintenance purchasing for a trucking company, we had one tractor that would randomly lose power. No codes, no cel..just a complete lack of power. After several tows, lots of checking and rechecking, an ECM replacement we finally put our technical director in the truck with a laptop so he could monitor all the various sensors. Turned out the boost sensor would randomly drop out, so the ECM would cut fuel- resulting in no power. This taught me the value of a "flight recorder" so every sensor output can be reviewed.

glad it was fixed

…….Tyler, yes….

I was having fuel pressure codes setting on my 09 duramax when the wife was drag racing it, I could put commanded fuel pressure and a actual and see the CP3 run out of steam, running 26000psi with 29000psi commanded on a full throttle pass. So on a turbo issue you could set up commanded vain position and boost and actual and if the turbo is doing as commanded you know it is fine.