Why does my boost keep decreasing and increasing?
Later
Allex
I understand your pain. My 09 SS has seen alot of our service dept lately. I have the same issue at times that you are having. I work in out dealer and the tech cant figure out anything wrong. I lost all boost a few months ago because the lower sensor hit the ac pipe and ripped the wires out. Since then, I have the same boost issues as you. At various times when driving ,the car will lose all boost and engine power. It happens a lot on the parkway doing 70.......I go to hit the gas and nothing.....no boost no power.......I have to keep tapping the gas until it finally comes back. Very scary doing 70+ on a 2 lane parkway........I have to coast until the power comes back. Techs cant figure it out. They gave me a data recorder hooked up to the engine computer to record the problem. I drove it for 2 weeks and wouldnt you know the problem didnt occur? I love the car but I have a lot of boost issues with it.......
Hmm, when the stage kit was first installed the boost cut out due to the bottom sensor hitting the AC.
The tech zip tied a hose back it was hitting and the boost doesn't cut out so maybe it's doing something else now?
The tech zip tied a hose back it was hitting and the boost doesn't cut out so maybe it's doing something else now?
It will be interesting to see in higher miles how the aftermarket tunes effect the life of the tranny.
The GXP GP also has the same tranny with a 300 HP V8. It may have 300 HP but the computer really kicks in at the shift points. The bragg how smooth it shifts and the truth is they power is really pulled back.
I understand your pain. My 09 SS has seen alot of our service dept lately. I have the same issue at times that you are having. I work in out dealer and the tech cant figure out anything wrong. I lost all boost a few months ago because the lower sensor hit the ac pipe and ripped the wires out. Since then, I have the same boost issues as you. At various times when driving ,the car will lose all boost and engine power. It happens a lot on the parkway doing 70.......I go to hit the gas and nothing.....no boost no power.......I have to keep tapping the gas until it finally comes back. Very scary doing 70+ on a 2 lane parkway........I have to coast until the power comes back. Techs cant figure it out. They gave me a data recorder hooked up to the engine computer to record the problem. I drove it for 2 weeks and wouldnt you know the problem didnt occur? I love the car but I have a lot of boost issues with it.......
You need to either push the tube on more to the intercooler or they will need to space the intercooler forward more with fender shims.
Under a heavy load on some SS the engine torques back and up in rotation on the engine mounts. This pulls the tube up and back wit the new t map making contact on the AC compressor.
THis will make it pop the pop off valve and lose boost then it regains it after the load is off and the engine is not torqued back.
I went throught this and so have others. The new T map is on a different angle and some SS need a little more clearance. It is a rare thing but just some need that exta 1/8 inch.
To look at the clearance on the lift it looks ok but people tend to forget the engine on a FWD under a load will move back and up moving this tube and sensor into contact.
Mine would drive fine around town but under WOT it would pop and drop pressure.
Mine alsp popped out the exhaust.
GM needs to update the kit instructions for the installer to measure the clearance on the T map. It needs some clearance. Witht he way the IC mounts it may not have enough. THe stock sensor is not an issue but the new one is.
Fender washers are recomended.
I figured out what was wrong and a GM Performance Division engineer gave me the fix for the dealer on shimming the IC. It is a easy fix once you find it.
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