Took the evo out tonight for a cruise with some friends. This car is my daily, I drive it 300-400 miles a week. As of this morning it was running 23 pounds without a hicup. This afternoon suddenly she is pushing only about 13psi for no reason. I checked my vacuum hoses best I could(in the dark with a crappy light) and saw nothing. Any ideas???

 

Does the car feel slower?

If not, gauge.

If so, lower MBC hook up or MBC itself. Thats close to WG pressure.

 

if ur vacuum tube goes loose on wastegate or mbc, you can spike dangerous hard so thats not it...... assuming its not the gauge malfunctioning maybe the line going to the gauge is kinked....

as smikeevo said.... a car going from stockish boost to 13 psi will feel COMPLETELY different... let us know

 

o yea it feels massively slower then usual. I checked the mbc, it is locked down solid. So it's settings have not changed. I was just under the car again and checked all the vaccum lines. They are solid with no tears. I just don't understand how this can come up out of the clear blue, well yes I do actually I am a former dsm owner haha

 

What brand of MBC do you have?

 

my mbc came with the car, not sure of the brand. Its made of brass and has never had a problem before. I dissassembled it and its totally clean inside.

 

you just cant "check" the hoses, you need to do a boost leak test. If everything is good with that, then i would replace the wastegate actuator. Same thing happened to me, and that was the fix.

 

what do u mean by locked down solid?

 

boost leak test is the first step

 

when your boosting does it make a bogging sound?