I'm having some really unusual boost issues today.

When i floor it in any gear starting at 2k RPM's it begins to build boost. It never hits 10PSI, around 6 or 7 id say. At 3500 to 4k RPM the boost drops all the way back to zero. Towards 4500 it begins building again but never hits 10 psi.

Anyone ever heard of this?

 

i assume that you're still running the twin turbo set up. it sounds to me that the secondary turbo has a little trouble kicking in. i think the primary turbo usually max at about 3-4000 rpm and the secondary should kick in about 4000rpm.

so i think that the secondary turbo has a little trouble kicking in. as for the max psi, it could be based on how the turbo is tuned. it may have been tuned to go maximum 7psi.

get your turbos check, and anyone pls correct me if i'm wrong.

 

sounds like a bad solenoid, or maybe one of your vac. hoses popped off, i had a similar problem.

 

Sounds like you are leaking boost somewhere. If you are still stock, check the large black boost hoses. You have to listen and check carefully. When not under boost conditions it can be hard to find splits in the lines. Also check the flexible connector coming from your y-pipe, these are prone to leaks sometimes. Next check you BOV but that seems less likely. Also, check all vacuum connections, particularly to wastegate and prespool actuators and solenoids. If it happened all of a sudden, it probably isn't serious, either a leak or something came undone.
Good luck.
--Jeff

 

My issue isn't as pronounced as yours but I have a drop/hesitation in boost arount 2K then it jolts back on and everything's fine....? Hope you figure it out.

 

could be a leak after the turbos . . . . .intermittent...prolly a solenoid tho

 

1) Start looking for boost leaks. Inspect every square millimeter of coupler/elbow before doing any other troubleshooting. There is good info in the FAQ under "boost leak"

2) If that comes out all clear, check the turbo troubleshooting links. Get the boost under 4500rpm working to 10psi. Then if you are getting 10 under 4500 and 0 above, follow the recommendations for secondary turbo troubleshooting.

 

Well i took another look at the FAQ today and pulled up the Turbo diag page. My intake pipe going to the first turbo is collapsed. I noticed this yesterday and uncollapsed it but it looks like it happened again. Is there something I can do to keep it from collapsing?

 

Replace it.

 

i hear they are like 90 bucks from Mazda. Not worth it when i can just save up for an aftermarket intake with metal pipes. Im just looking for something temporary.

 

Get it from Ray Crowe at Molloy Mazda. . .and make sure your air cleaner is new/clean.

 

Who said you needed to buy a new one?

A used one will work just fine.

 

What would cause the pipe to do this anyway?

 

Boost

 

Who noticed you intake piping collapsed and fixed it? I have worked on this car and it has newer couplers and a few of the IC hoses have been replaced....it is not leaking from the intercooler piping. The turbos are also blowing quite a bit of oil, obviously thats not causing the problem, but they're on the way out.

-Dan

 

Oh excuse me! haha i was going to say Scrub took a look at my car but figured it was just easier to say i noticed the hose caved in... next time i wont make that mistake Dan. :P

 

Intake restriction causing a slight vacuum in the hose.

Dave