I replaced my Exhaust with a 4'' turbo back and blocked the EGR thinking the cat was plugged, but still running 800 degrees at 60 mph (no load). Hit a 6% grade with Horse trailer and bogged down. My boost will max out at 20psig but somethings going on .Help

 

what else have you done to your truck? is it stock?

---AutoMerged DoublePost---

have you checked your intake?

 

I have An "Edge juice with attitude" installed mainly to monitor engine temps and boost.I had this Problem before the edge tuner.The high temps are present at stock tunning. I bought this truck used with 70000 miles. Everything else is stock

---AutoMerged DoublePost---

No I haven't checked the intake what should i look for?

 

air filter?

 

i get crazy high egts under half throttle with no load on the truck, was told by shops that most likely the variable vanes on the turbo are stuck in one position.sounds like you may have this problem also. for some reason it doesnt throw any trouble codes though.that would also maybe explain why your only gettin 20psi boost!

 

ah yeah KC had this problem too, turned out it was his vaines getting truck

 

You guy's are probably right. What should my max boost be? What can I do to fix this problem? Also I noticed sometimes when ideling,the truck sounds as if there's a warm up valve like the ford has and then it will change pitch as if it opened.

 

Yep, Vanes are hanging....Time for a PCV re-route and a EGR Delete!

 

Thanks for the help. This is my first GMC Duramax,I was a Ford man for years. Even with theses Problems I won't go back. The EGR is now blocked but haven't rerouted the PCV. What will fix the sticking Vanes?

 

$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ $$$$$$$$$$$$$$$$$$$$$