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brinker · #1 (**permalink**) 09-15-2010, 08:17 PM

Ok I have used the search feature and haven’t really found anything to really help me. I have a 05 f250 when I got it this spring before I did the exhaust, head studs and egr delete when I was at WOT I would be at 25-28 psi or so. After doing the work when I’m at WOT Its normally around 20psi once in awhile I have seen it shoot up to almost 30 and then the truck shifts and it drops down to 20psi. If I am in OD and ease into the throttle I can get the boost up to 25-28psi but by that time I’m doing 85+ But if it downshift the psi drops. I know I have a small pin hole in my Y pipe on the driver’s side at the edge of the flex section but it was that way before could it of gotten worse and be causing this? I went with a sinister egr kit with new up pipe. I have check for lose clamps and misaligned exhaust pipes and haven’t found anything the truck still has a lot of power I don’t have a programmer on it yet. Any ideas? Thanks

brinker · #2 (**permalink**) 09-15-2010, 09:14 PM

Oops meant to put this in the General discussion

Lilpooh · #3 (**permalink**) 09-15-2010, 09:19 PM

Do you have the egr valve plugged in and tied up to the side.

brinker · #4 (**permalink**) 09-15-2010, 09:23 PM

Quote:

Originally Posted by Lilpooh

Do you have the egr valve plugged in and tied up to the side.

I had it plugged in for a month or so after i did all the work. Then i desided to see if it would thro a CEL and it didn't. So right now no its not but it was like this with it plugged in. The truck runs great just wondering why its not building as much boost at WOT

Lilpooh · #5 (**permalink**) 09-15-2010, 09:46 PM

With certain PCM stradegy's, the VGT and clutch fan will not work properly with the egr valve unplugged. You may have sticking vanes in the VGT.

brinker · #6 (**permalink**) 09-15-2010, 09:56 PM

Quote:

Originally Posted by Lilpooh

With certain PCM stradegy's, the VGT and clutch fan will not work properly with the egr valve unplugged. You may have sticking vanes in the VGT.

I was starting to think they might be sticking but i hear then cycle when its idleing. I was thinking about pulling it off the winter and cleaning it and replaceing the Y pipe. If they were sticking would i still be able to ease into the throttle and get full boost when in 5th/overdrive?

Lilpooh · #7 (**permalink**) 09-15-2010, 09:59 PM

Quote:

Originally Posted by brinker

I was starting to think they might be sticking but i hear then cycle when its idleing. I was thinking about pulling it off the winter and cleaning it and replaceing the Y pipe. If they were sticking would i still be able to ease into the throttle and get full boost when in 5th/overdrive?

IDK, someone with more knowledge will have to answer that.