a possible fix for weird boost patterns
 

i might have found an solution to a problem of mine. i had printed out basically the whole rob robrobinette website and put it in a notebook. now i have found reading a setion in engine related notes subbtitled boost problems, maybe my solution. i have what i think is 8-5-5 boost pattern. . i also have a high idle at about 1000rpms. i at first thought itd be just a blown hose but saw many posts about other possible problems, so i thought it was something else. because of all the other possibilities i forgot the simple possible solution a simple blown hose. i mean how many people who have this problem had their hoses checked. maybe some have but im sure there are some that havent well i hope this helps somebody thought it was somthing alot more complicated because my second turbo wouldnt kick in. well it say a hose can be blown anyways heres what it says....


Boost Problems

See Derek Vanditmars' Turbocharger Troubleshooting Guide (excellent)

7 psi boost usually indicates a hose blew off somewhere, whether it be a small one that is preventing everything from functioning correctly (usually associated with a high idle > 1000 rpm), or you have a split in one of the main pressure side intercooler hoses. If your idle is lopey, and jumps around from ~400 -> 900, and engine sometimes just dies on you when you come to a stop, then you most likely do have a cracked apex seal, or stuck one. A compression test will verify this. Now if the car won’t make much power below 2500-3000 rpm, then you have major apex seal failure.

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I would bet your problem is the same as mine was. I fixed it without pulling the upper manifold as I had did the first time while replacing all hoses with silicone. The loose hose is very difficult to see. Under the manifold there is a row of about 7 or 8 solenoids. There is one with a white connector on it. This is the solenoid that is 2nd back from the forward side of the manifold. When I say forward I mean in referenced to front of car. That is the Turbo Control solenoid. below the connector is a plastic port facing the turbo side of the motor. This hose, in my best guess, has popped off or is loose. To get to this solenoid you need move the two solenoids that are mounted next to each other on the forward side of the upper manifold. These are the Wastegate Control and I forget the name of the other. Unbolt these two and move them out of the way to gain better view of the hidden Turbo Control solenoid. Take some long needle nose pliers or a long screwdriver to poke at the hoses to see if they are loose. If in fact this hose is loose, I would replace it completely with a silicone piece. I used a drop of glue and tie-warps to make sure it never it comes

.... well i know many people have this problem so hope this helps some. i will know tommorow after i try it.