Since ive had this truck its been one thing after another, I get one problem squared away and next week its something new. I finally got my idle knock taken care of, now I dont have any boost. I use to make 20-22psi max, now its down to 14psi. I started checking for leaks, and found the clamps on my downpipe and the one from the turbo to the Y were no good. Also Im missing a blot on the topside of the exhaust flange adapter, so I get one off the old turbo and put it back in with some loctite, along with new clamps. Still only 14psi max with no boost till 2k rpm, unless im on the highway then I make about 5psi at 75 mph, 1600rpm. Also the bolt I put back in has not fixed the leak, but I wouldnt think that would affect boost since its after the turbo. The truck feels like the ICP is in limp mode, but the sensor checks out with A.E. I dont know what else to check, any ideas?

 

Your only turning 1600 RPM @ 75 ??? I know thats not your original complaint but something doesnt sound right there either .

 

have you checked all of the intercooler boots? Its worth a try to take them off, clean em real good, spray some hair spray on them to keep them in place, and try it again.

 

I running 70mph at 1800 to 1900rpms on my 01 cc

 

Does anybody have pics of the intercooler boots and where they fail? Pics just really help me a lot when reading this stuff..

Thanks

 

They're the blue & black boots between the tubes that go between the turbo and the front of the truck. I'd check 'em all since you're in there. Don't forget the orange ones under the turbo manifold.

How tall are those tires? That might explain the lower rpms at 75. I'm a hair below 2000 at 70 with 265-75-16s & 3.73 gears.

 

O.k. let me take a stab at this. how long ago did you put the van turbo on? Is that when you noticed the lower boost #s?
I see no tuner or chip in your sig.

The van turbo has a 1.15 A/R drive side. Due to the larger more free flowing A/R of th van turbo IT WILL TAKE LONGER TO BUILD BOOST WITHOUT THE EXTRA FUELING OF A CHIP. I drove my truck a little while ago and set the DP tuner to my stock setting. I could not reach more than 18PSI. Now with my tuner in the 80E, or the 120R setting I can hit 23PSI you are not having a boost leak, you just dont have enough fueling to spin the turbo drive wheel fast enough for the compressor wheel to build the boost higher. It will be 2K rpms before the van turbo really starts to build boost.

 

Ive got 33"s and 3.73 gears, and the rpms I gave arent presice.

Ive had the van turbo on for over a year now. Im use to the lag, but my truck flat out falls on its face when I go WOT. I tightend up the clamp on the Y after driving around a little more and it helped. Now im making 2-3psi while under 2k rpm "light throttle", which is normal from what I remember. If im on the highway at WOT and reaching the top of 4th gear "auto" I can just about make 16psi. Thats when my van turbo use to really shine and it would just keep pulling, topping out at 22psi.