decrease in boost pressure

lost1 · Post by **lost1** » Thu Dec 14, 2006 7:47 pm

I just noticed that my turbo boost pressure has dropped 5 psi at maximum load. Any suggestions why this happened?

mitch · Post by **mitch** » Sat Dec 16, 2006 11:17 am

You boosted your turbo right? not to be a downer, but you think you might have fried a seal or lost compression??? Only a guess hav'nt worked on mine yet

Mitch

lost1 · Post by **lost1** » Sun Dec 17, 2006 8:37 pm

hope not, its pretty much a standard modification...

lost1 · Post by **lost1** » Mon Dec 18, 2006 9:45 pm

I may be getting closer. I found a site on the internet that says if the Relief valve (blow off valve) isn't working right, that it can reduce the boost pressure. Don't really know how I can fix this, but I will have a look in the coming days...

VADLEM · Post by **VADLEM** » Sat Dec 23, 2006 4:25 am

could be the relief spring is going soft or a vacum leak in the actuator line

lost1 · Post by **lost1** » Sat Dec 23, 2006 1:05 pm

Well after cleaning air filter and intake tract, wastegate, and Relief Valve in additiong to jiggling and playing (using a bicycle pump) with the vacuum actuator. I have yet to find the problem.

I will try and have a better look and see if I can find a vacuum leak on the actuator line.

thanks for the advice

David · Post by **David** » Sat Dec 23, 2006 4:42 pm

How does one notice a drop in turbo boost pressure of 5% under max load?

Chewy · Post by **Chewy** » Sun Dec 24, 2006 9:36 am

5psi ( lbs per sq. in.) :P with a boost gauge 8)

if there is a leak on the actuator line, you will increase boost. check all of your charge pipes if you already havent, if you know someone with a compressor and a regulator that makes it far easier.

as well, I'm not too sure about Deli's in this sense. but you may want to check that the bolts are tight holding the exhaust manifold to the head and as well the ones that hold the turbo to the manifold, they can back off and you don't even notice the sound change over the usual diesel valve clatter, either that, or the gasket between the mani and the turbo.