I have an F-450 service truck and for the last 7 months I have had problems with boost during regen. I have a video to prove it and will try to attach...the video shows me going from 0-75mph with my foot on the floor. I've replaced the turbos, an exhaust manifold, the exhaust filter, and still the same. When it is not in regen, she'll run great, bout 34 psi boost, but it is just not right and want to know if anyone else has had this problem and what they did to fix it. I've also noticed that the harder I run it, the less boost I get out of it. At times, I get 15 to 22 and it fluctuates. I am a natural gas compressor mechanic and I know that if this is the way they run, Ford would have never sold this. The truck has 145K on it and it is on it's 2nd engine as of 97K so please help!!!!!!!! I've had it to Ford and aftermarket services and still no fix.

 

Is it setting any codes? If so what are they?

 

Yes it throws a turbo pressure code all the time. The shop can't figure out why.

 

what code?

 

I'm not sure what the code number is. The shop just said it was a boost pressure code. I can ask them tomorrow when they open.

 

I had one once and they replaced my high pressure turbo. It was 3.6 or psi out of spec. Mine was an overboost issue though.

They diagnosed by commanding the VGT and then the amount of psi it was producing with the VGT commanded to 90%.

 

I see. Mine doesn't get enough boost. Hell my 94 F350 turbo diesel has more snort than this thing and its a crew cab.

 

so your maybe either the VGT is stuck or maybe the same just the complete opposite.

I think they should start there. You can command the VGT thru the pcm. They hopefully have the ford ids program to do so.

 

Yes they have everything. Actually the mechanic is an ex Ford Technician but he's never seen one do this before.

I'm going to take it to a dealer one of these days.