possibly boost leak.....

[fuzzybmx]

I took it into the deal and they said everything has checked out fine. which doesn't make any since. the boost is still on the low end when it has never been like this. anything else i can look at? I'mdesperate!!!!

 

[Darth Vader]

Well, a Dashhawk or your AP can give you WG duty cycle, which will tell you the percentage that it's open under driving conditions. You can physically test it by getting under the car, disconnecting the vac lines to it, capping one and pulling a vacuum on the other and seeing if it holds. This is difficult to get at, though.

Did you check the hoses to the boost control solenoid? That's the second (little) hose off the wastegate and another small one near it as well, going to the intake. Leaks here will cause low boost.

 

[fuzzybmx]

I'm not sure how to read the wastegate duty cycle from the AP. I'm not sure what the numbers mean or what they should set to.

i have not looked at the small hose from the intake to the boost control solenoid to the top of the wastegate. i will do that!

So the test the wastegate i have to pull the hose from the bottom of the wastegate going to the turbo?
As i am going along with all of this i am learning how all of this works.

thank you for thr reply. the dealer ship is full or s***! I know there is something wrong with it.

 

[Darth Vader]

I have a Dashhawk so, I can't speak to how to read it off the AP but, WG duty cycle just measures how much the WG is open during engine operation. If it's opening too much too early, that will bleed off pressure and can cause low boost. Primary cause for high WG duty cycle % are too free flowing exhaust on a too small turbo but, typically you'd be getting high boost spikes or boost creep if this was the issue, not low boost overall.

Make sure you check both hoses from the boost control solenoid for integrity.

You can isolate the wastegate operation another way, too. You could disconnect the boost control solenoid's electrical connection and retest. You should see 15.6 psi or more if you do this, as there's essentially no boost control at that point.

If it manages that, then the WG system may be where the problem lies. If it passes the "suck and hold test" on the hose, it's the boost control solenoid to look at next. Frankly, any issues there, I'd just ditch the whole stupid thing and put in a manual boost controller.

Simple stuff also, have you changed fuel recently and have you datalogged how much knock retard you're seeing? If the car's knocking, it's going to pull timing, close the throttle plate, WHY, to bring the knock under control, and that could gauge as low boost.

How's the car running, is it feeling weak and flat? Or is it running well?

 

[fuzzybmx]

Thanks for the reply!!
I will check that stuff out with the WG and the solenoid on Thursday night. I'm on-call with my work and am driving a work car at the moment.
Also when i disconnect the solenoid and i do see the 15.6 psi that means there is something with the WG or the solenoid?

The fuel is the same only 91. I was watching my KR and it was going up. But I was able to get that under control. when ever I am not WOT it will go to 5.9 for no reason that i can see.
It seems the car could be giving me a little more power.

 

[Darth Vader]

Like I said, if you disconnect the solenoid and get 15.6 psi or better, chances are the issue is with the solenoid or its attendant hoses and connections.

If you are hitting KR alot, Seafoam the engine and start using 94. I always use 94 in this car and I never get KR. If you are seeing KR, that's why your boost is low and your power's off.

 

[Silver Ecstasy]

Hell, he may not have 94 octane access. I know I do at Sunoco around here.

 

[fuzzybmx]

I dont think I have access to 94 octane. where do you live that you do?

 

[Darth Vader]

Left coast of Canada.....

 

[Silver Ecstasy]

Well I know Michigan Sunoco stations carry 94 octane.

 

[fuzzybmx]

hey every one! So I disconnect the solenoid and i was getting 10-11 psi is all gears. would that mean the solenoid is working?

 

[fuzzybmx]

I just ordered step 1 colder plugs. i still need to check the 3 hoses vacuum lines.
I feel like calling mazda again and telling them this s*** aint right!

 

[Silver Ecstasy]

If you're that worried about it, I think you should be taking the car in to the dealership, stock.

Colder plugs isn't going to help.

 

[fuzzybmx]

but the thing that sucks is that i did take it in there and they worked on it for 2 hours and they claim they did not find anything wrong. i just feel stuck.

 

[fuzzybmx]

here is a log from today. how does the WGDC look? i really dont know where it should be at.

 

[Silver Ecstasy]

It looks like to me that your wastegate is staying closed more often to create little to no boost. The system looks like it sees the low boost and is doing what it can to generate boost but you're only hitting 11's and 10's.

1) Check intake tract, all clamps, hoses.
2) Tighten boost tubes (1 hose going from turbo to intercooler, 1 hose going from intercooler to throttle body)
3) Spray MAF with MAF cleaner, let dry
4) If nothing...you've gotta go to dealer.

 

[fuzzybmx]

thank you very much for the reply!! i will do this tonight!
one queston. can i get the MAF cleaner from like a auto zone?

 

[Silver Ecstasy]

Yes, absolutely. Be very careful not to drop your MAF sensor when you remove it. It's a very delicate piece and costs $140. Main idea with the MAF is to spray it and let the residue drop. Then let it dry.

Otherwise, you've got a connection loose somewhere. What's your mods again?

 

[fuzzybmx]

my mods are the AP, test pipe, and a cp-e nano SRI, and cobb XLE BOV.

 

[fuzzybmx]

could a fuse for the MAF gone bad? A little while back I did the mod for the fog lights. To have them on when the parking lights are one.