Need Help! 04 Mazdaspeed stutter issue

[Funkdenomotron]

Howdy.
Not sure if this goes here, but I will put it here anyway. I have an 04 Mazdaspeed with the FM complete intake kit. I got the kit a few years ago, so it did not have the o2 signal modifier, and it had that crappy brass looking manual boost controller. Lately the car has decided to stumble a bit under full boost/load around 4000rpm, and again 700 to 1000 rpm later, and only in 3rd through 6th gear. It is not completely falling on its face like it is hitting boost cut, and I was afraid the spring was wearing out in the old boost controller, so I checked it. It was pretty oily and gross, so I got the Turbosmart Boost Tee and installed it today. The problem has not gone away. I have the O2 signal modifier on order now, will have to wait a week. Hopefully that fixes it. Anyone have a similar problem, advice, solutions?

Thanks and be groovy!

[cjsafski]

I had a similar problem a while back in my dad's msm. There is a valve related to the emissions stuff that causes this sometimes. Cleanining it helps. Sorry though I don't remember excatly which one it is but if you search around there is a lot of infor on this on the net.

[tanakapz]

famous MSM bog issue. hard to fix, need to clean the solenoid valve.

[Funkdenomotron]

Cool thanks! will try that.

[Funkdenomotron]

Thanks guys. I cleaned said solenoid valve yesterday, and most of the stutter is gone. I was not able to find the silicone spray to lube it, but cleaning it out really helped. There is a bit of stutter at around 3k still, but something tells me I need to check hoses. There is one hose in particular that looks like it could be collapsing under vacuum. I will replace, and put in the o2 clamp this weekend.