2006 6.0 diesel. P0299 turbocharger underboost code is on. I noticed when i first took off it didn't seem to have that boost most of them have with that variable turbo vane system. The check engine light was on. I nailed it hard, it showed 30 psi boost then turned on it's little wrench light and pulled the boost way back. 145k miles. Feels like a nice tight truck but she don't have the poop. When the wrench light is off it has more power, but still not right. Where do I go from here? Thanks Jack
Hi, I am John Mc, a Ford dealer tech. I hope I can help you quickly and accurately. One moment while I work on your problem.
There are two common things that can cause this problem. First is a sticking open egr valve. To check this you remove the valve and see if it is stuck open. If so clean it and retry. If ok you probably have a turbo issue. The vanes will stick from carbon buildup or a worn cam ring in the turbo. To fix this you have to disassemble, clean the vanes and replace the cam ring if worn.
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is the egr valve that little pot with an electrical plug sitting right behind the big intake air pipe going into the manifold? If so, it looks brand new. I thought I might be visiting the turbo. It's been turbo month. Audi and VW last week. I've heard those variable vanes have problems. I just removed the two bolts from that thing I think is the egr valve and I can rotate it, but it's stuck, I can't pull it up. Help Thanks jack
Yes, thats the egr valve. Use some large channel locks and pull up with the pliers and it will come out. Just takes a little force.
hard to get out. that looked fine. the dual valve seat egr. shaft moved easily, was closed when removed. Cleaned and back. Had to use the mount bolts to pull it back down even with WD40 on the o-rings. Just came back from around the block. Still poor off the line performance but much better shifts on the flat out try. The first time (before egr clean) she had to think about shifting when maxxed out, this time she pulled real strong and shifted well until, blink, the wrench lit up. No check engine light though. I am surprised the egr cleanout seemed to have some effect. This is the first 6.0 I can hear the blow off valve on. It sounds kind of sick when you lift under boost. Any more thoughts? Thanks jack
If you hear air chatter you definately have a turbo issue. Take it off and take it apart. Clean it and if the ring has any wear replace the ring. Very common. Egr was probably sticking a little making the problem worse so you are getting there. Just take your time with the turbo and mark everything so you put it back together in the same position. Remember you are only messing with the hot side of the turbo.
The exhaust side of the turbo? I've always wanted to see how one of these works. That will be for another day. I'll get back to you, thanks, jack