So first off, I don't have a very high post count because I spend the majority of my time searching here on the forums. I've been on the hunt for turbo gremlins for a while now (just about since I bought the car.)

This weekend my father and I will be trying to trouble shoot my twin turbos, I'm wondering if anybody might have some tips for me?

::PATTERN:: 7-5-3

What I have planned: First things first, I'd like to get my primary spooling 10 PSI, then I'll move on to the secondary issue.

Things that might possibly effect primary boost:
1) Boost leak : I have checked the infamous y-pipe coupler, no rips. No rips in either of the intercooler hoses either. Also, there isn't any audible evidence of a boost leak, which from my experience is usually the case.

2) Wastegate : Backstory -- I have swapped out the turbos for a healthier set, along with the waste gate -- same issue; the primary only boosts 7psi given different turbos and a different wastegate.

3) Wastegate/precontrol rod lengths: Both actuator c-clips are nice and snug, the doors are sealed just fine when closed so this doesn't seem to be a problem.

4) Wastegate/precontrol pills : I have checked the hoses, no expansion in the hoses, the pills are both there.

5) Wastegate/precontrol solenoid: Replaced 1 day ago with a new one from Malloy; I just about quadruple checked the plumbing and hoses to/from these solenoids. The harness connectors are NOT backwards, I also double checked that.

So these are the things I have checked/replaced. Any other ideas on what could be causing 7psi on the primary? To me it seems like the wastegate is opening at the mechanical spring pressure, instead at 10psi via the wastegate solenoid.

My dad is going to check my wiring harness resistance as well as my ECU. Our hopes are to rule out the wiring so that we can move on to other possible problems. I was also thinking that maybe the precontrol door might be opening too soon robbing me of primary exhaust gases, what would cause this? I have also replaced the majority of my turbo system solenoids......any ideas??

 

Much of the control system for the turbos is vacuum activated. If you have a leak, or a bad check valve, that will affect activation of the system. Old hoses, and/or bad check valves may be your problem

 

Forgot to mention I did the vacuum hose job when i replaced much of the solenoids. I also replace all my check valves with Viton ones courtesy of Dale Clark.

 

Plugged cat!

 

+1! Check your cat out... it could be clogged up!

 

too much backpressure(bad catalyzer) or a bad secondary turbo

 

I am having a similar problem and the only old thing on my car is the stock cat. The hose job is brand new with viton hoses while my engine was out, simplified twin turbo and all block off plates.

 

I don't wanna steal this guy's support, but I'm in a bit of turbo trouble too...Just my 2nd turbo though. I don't have a boost gauge yet but thats #1 on the to-do list, but for starters I already replaced the pre-cat along with every fluid in the car. Anyone have any guesses, or know of very common problem areas with the secondary turbo? I wish I could see my boost #'s ...

 

So I took the advice of fellow rotorheads and checked my cat. Sure enough, the thing was clogged to all hell. 2 hours, and 1 high flow cat later, the car boosts 10-8-10-7!!!!! I"m VERY happy although the boost seems to drop to 7 toward the end. Finally, i get the feeling of what my car should really feel like!

 

Awesome, i always like to see success stories.

-Ben

 

Without a boost gauge your guess is as good as ours.

 

Check this link...lots of good info

http://www.autosportracetech.com/RX-...leshooting.htm