I've been sorting through as much info as I can absorb today and with out getting carried away i thought I'd post to see if I'm on the right track. Problem is boost pattern is 10 to 4500 drops to 4 climbs to 6 in 3gr to redline. In second gr it hits 10 drops to 5 at 4500 then decreases to 2 at redline? Is it possable for a stock pre cat to cause this or does it sound like it something else is up (solonoids or leak or actautors?) I'm new to all this and my brain hurts (overload of info). aftermarket dp is on order but I get the feeling it may not be the only problem? Thanx

 

well man mine did this. I think it can be generally either 1 of 2 things. Maybe and check valve that is not being able to keep boost from seeping back out. That explain the boost seeping down to 2 and also a question. Will the car build boost when you change gears rapidly. Or to be general it could be a secondary boost problem on the intake side. ie vacuum lines, solenoid, coupler, etc... Good LUck hope this may help

 

also check your couplers, they are known to crack, thus boost leak

 

The dp should help, but it won't fix all the problem.

First check for leaks in the intercooler couplers, then look for popped-off hoses.

Second, replace or inspect the check valves, especially the two green/black ones.

If all that looks good, it's probably a bad solenoid or actuator leaking.

Dave