I just got my new up pipes put on as well as a 38R and pulling a hill hard my truck will hit about 22 psi then drop off slowly I have an electronic boost fooler wich has been on the truck since new pretty much but I don't get a CEL at all is this what I should be getting and I was on the 80hp tune? I ordered new boots and plenum inserts they just haven't got here yet. I know I had a leak before on my old up pipes because they rattled every now and then and I could see exhaust coming out of them when it was cold out but I could hit about the same 22 boost with my old setup. So pretty much nothing changed boost wise except it gets up to boost faster now. I would say it's defueling but I was always told the CEL would come on if that was the case.

 

Where are you reading the boost with that boost fooler on there? The fooler renders the OBDII reading useless on boost above 22 PSI, so I bought a separate gauge for boost with my pneumatic boost fooler from Riffraff Diesel. Here is a sample of the readings I could reach with stock sticks, stock turbo, modified air, and a chip:





Since upping the injectors and going to a 38R, I limit my boost to 35 PSI - no point in pushing my luck with 300K-mile valve springs.


Defueling occurs at a specific RPM on a stock program, not at a specific boost - and it will not throw a SES light when it does occur.

 

Reading boost off the MAP with a Boost Fooler, I get a reading of 23lbs. Using the probe inserted where the AIH used to be, 30lbs is easily obtained with my set up now. Back when I had stock turbo and sticks, I could still hit 30lbs of boost, it just took it longer to do that!

 

I'm reading boost out of the AIH port. I was googling a bit and saw that people were having to adjust the waste gate on the 38R from the factory I had a shop put it on so I don't think they adjusted at all so pretty much I'm guessing it's set from whatever garret set it at.

 

So would in plugging the red line be the same as cranking down the waste gate just to see if that's what it needs?

 

Yep... stock wastegate setting on the 38R is 22 PSI boost. If you tackle adjusting it in the truck, have a mega-magnet nearby to catch that stupid C-clip when you drop it.

 

Ok so I disconnected the Red line and I can hit 30 psi but it takes a lot of effort but anyways was going over the pass this weekend and the turbo surged on me twice. I thought the 38r wasn't supposed to surge?

 

She'll surge in the right conditions. There are different wheels you can switch out if you like to rid yourself of that situation. I personally just drive it. And if it surges, I just let off the throttle till it stops.

 

Which tune do you use to get the 30 PSI? Even with the red line mod, the wastegate spring can still let go if it's set too loose. I jacked mine pretty tight and I have the red line connected... but I have more fuel at my disposal (0-40 boost gauge top right):

 

80HP tune I still haven't tightened down the waste gate just disconnected the red line I have the Banks Big boost on my stock turbo that I was game have them put on the 38R but the shop said the one that came with the 38R was about the same quality. I will try tightening down the waste gate rod I also made a Boost leak detector just waiting for the weekend

 

Yeah my boost gauge doesn't shoot up that fast I will try to take a video of it if I can figure out how to post it on here.

 

Not sure if it's showing up or not but I kept it at a constant throttle once it hit the 28 psi mark

 

I saw it... boost leak. I am very afraid your gauge did the signature "twitch" of an intake plenum leak. I'll explain that better:

When a boot leaks, it's reasonably constant. When the plenum seal is compromised, it makes a raspberry (or fart) when the upper boost numbers are reached. I hope I'm wrong, but do the boost leak detector thing and really focus around the intake plenum seals. Stock sticks, stock turbo, 80 HP tune (before my big mods):





Aaaand here's when I first noticed a small leak in the plenum:

 

I got my new boots and plenum inserts also but I will do a leak test before and after