Still can't boost above stock level... [Archive]

unwrittenLaw

09-19-2003, 01:51 PM

Ever since I went to the dealer about a month ago to check out a CEL, I have not been able to get the boost past stock. I've checked the lines, tried 2 different MBC's and still no luck. I can't get a good look at the wastegate, but the line from the T to the wastegate looks normal. The dealer did something to my car and its pissing me off. I can't really go back and ask them why I can't boost past normal level, so I don't know what to do...
Did they adjust the wastegate or something else?
I'm just really frustrated...any suggestions?

boostisgood

09-19-2003, 03:19 PM

You cant adjust the wastegate like that. If they put in a different spring, it will open at a different PSI.

What a Boost controller does, is bleed off some of the Manifold pressure, being sent to the Wastegate, to trick it into seeing the predetermned PSI.

I would suggest getting your hands on an EBC. IMHO, the price difference is MUCH worth it. :D

II-Savy

09-19-2003, 03:45 PM

http://www.boostcontroller.com/alert.php

Maybe this one would help....it looks nice and it seems to be solid. I have no deep knowledge at all with these but maybe more fine tuning with the controller is what you need.

jred321

09-19-2003, 04:26 PM

what does your vacuum read at idle? and have you tried doing a leak test on the at the turbo to make sure there are no leaks? i mean by hooking up a rubber tube to the intake side of the turbo and using pressurized air to fill it, watching your boost gauge and listening for leaks.

unwrittenLaw

09-19-2003, 05:30 PM

At idle it reads like -70 to -80 hkpa, which is what it read before I had problems The boost readings seem fine, it holds boost at about .36-.38 under load. The pressure seems steady so I don't think I have any leaks but not 100% sure. I haven't tried doing a leak test..I can't get to the turbo very easily. I'm going to a different dealer next week to have them look at it. I told them that its not boosting as much as it used to. Its just strange that my mbc was working fine before I took it to the dealer, and now 2 different mbc's wont raise the boost one bit...

unwrittenLaw

09-19-2003, 05:32 PM

Originally posted by boostisgood
You cant adjust the wastegate like that. If they put in a different spring, it will open at a different PSI.

What a Boost controller does, is bleed off some of the Manifold pressure, being sent to the Wastegate, to trick it into seeing the predetermned PSI.

I would suggest getting your hands on an EBC. IMHO, the price difference is MUCH worth it. :D

Could they have put in a new spring? I was there for about an hour or so...but I was watching them for some of the time, and it didn't seem like the tech was doing anything major. But I don't know how hard it is to change out a wastegate spring...

unwrittenLaw

09-19-2003, 07:33 PM

I checked for leaks by covering the intake, and it stalled out...so is it pretty safe to say they're aren't any vacuum leaks?

jred321

09-19-2003, 08:12 PM

i would say that's safe to say, and changing the spring shouldn't make a difference when turning up the boost, just turning it down, since the pressure is bled off, so i'm out of ideas as to why you can't turn up the boost if everything is how it should be.

chinkysuavo

09-19-2003, 09:04 PM

were u able to boost higher b4 u had the CEL issue? And, did u remove the MBC b4 taking the car in? Could it be one of the lines from the MBC are loose?

unwrittenLaw

09-20-2003, 09:56 AM

Yeah, I was able to boost higher before the cel came on and after. But the next day I took out the mbc before I went to the dealer. I waited a couple weeks after I went to the dealer to put the mbc back in and thats when the problem started. The cel hasn't came back on since I got the reflash though, so I think it was just a fluke or something. And I've checked all the mbc lines, and like I said, I've also tried 2 different mbc's...

unwrittenLaw

09-21-2003, 12:54 AM

Well the CEL came back on again today while I was driving on the highway...I wonder if whatever is causing the CEL is also restricting the boost...

chinkysuavo

09-21-2003, 12:57 AM

hmm, is ur intake temp sensor connected and seated properly? i know that will make the CEL come on, or it could be an exhaust leak, check around the O2 sensor after the 1st cat...other than that, I'm stumped bro.

jred321

09-21-2003, 01:10 AM

what is the cel for? get it scanned at like autozone or wherever does it for free because they could be related.

unwrittenLaw

09-21-2003, 09:43 AM

Well when I first went in to the dealer for the CEL, they couldn't pinpoint it, but said they had a 'boost concern' which they thought might have affected the Variable Tumble Control System (VTCS). But they wanted me to comeback and leave it overnight so they could test it cold..I never went back because I didn't trust them. Then the CEL went away for awhile and now its back, but I'm going to a different dealer to have them check it out this time, and hopefully they won't have a "boost concern"...i hate dealers..

unwrittenLaw

10-24-2003, 03:06 AM

Update:

The CEL was fixed..seems there was a blockage in one of the check valves in the VTCS (variable tumble control system). So they put in a new check valve..the CEL did come back on briefly but hasn't lit up for about a month now..so I think its ok.

But, I went out and re-installed my Joe P MBC, checked all the vacuum lines, adjusted the MBC...and started driving. And once again..I can't get above stock boost...I don't know what could be causing this...anyone have any ideas?

Dexter

10-24-2003, 03:44 AM

youre 1000000000000% sure you are installing it correctly?

unwrittenLaw

10-24-2003, 03:59 AM

Yeah, I've uninstalled/reinstalled a lot and even tried a different boost controller...its like its not even there..no increase in boost, although it does seem to spool up a little faster according to my Blitz DTT/Guage

Aricjm15

10-24-2003, 04:42 AM

install the boost controller as close to the waistgate as possible, directly to the line coming off of the waistgate, there should not be ANY hose T's between the MBC and the waistgate

other than that I have no clue what it could be

unwrittenLaw

10-24-2003, 05:23 AM

Yeah, the place where its installed is as close to the wastegate as you can get, its on the line directly from the wg...

MazdaDryvr

10-24-2003, 07:30 AM

I dont mean to thread jack, but when you said...

but said they had a 'boost concern' which they thought might have affected the Variable Tumble Control System (VTCS).

Did the dealer explain what this system is? I have my MSP at 9psi with JoeP MBC and I have been wondering if the extra boost will affect the car. They never reset my ECU and I wonderd if that should be done?

unwrittenLaw

10-24-2003, 08:59 AM

Perfworks gave me this info on an earlier post about my CEL:

VTCS (variable tumble control system). There are a set of throttle plates right before head port. and right before the fuel injectors. under cold start up and until the engine reaches at least 65 degreesF, they stay closed. there is a small slit that allows a "tumbled" air charge to pass thru and mix with the fuel injected. This tumbling continues down the intake port and thru to the combustion chamber. Is it supposed to help with cold start emmisions by creating a more complete and efficient burn . That along with the first cat are supposed to make the vehucle a 50 state legal smog emmiting vehicle.
the plates open when vaccum is allowed to pass the VTCS control solenoid mounted on the intake manifold.

zzooomm

10-24-2003, 09:54 AM

At the tee pull the line that goes to your wastegate and see how much boost you get. Before flash I was at 22 but after flash I can only get 12.

MazdaDryvr

10-24-2003, 10:07 AM

thanks unwritten! :)

unwrittenLaw

10-25-2003, 02:32 AM

Originally posted by zzooomm
At the tee pull the line that goes to your wastegate and see how much boost you get. Before flash I was at 22 but after flash I can only get 12.

You had 22 pounds of boost?

Notorious

10-25-2003, 04:29 AM

I highly recommend that you don't do that. Driving without a wastegate is bad.

SpicyMchaggis

10-25-2003, 04:30 AM

yo go to mazda and be like..look bud..im fucking punk rock..fix the shit or i'll mosh on your face.

unwrittenLaw

10-25-2003, 05:16 AM

Originally posted by Notorious
I highly recommend that you don't do that. Driving without a wastegate is bad.

yeah i know..i was wondering where he got 22 pounds, if that's what he meant :confused:

unwrittenLaw

10-25-2003, 05:17 AM

Originally posted by SpicyMchaggis
yo go to mazda and be like..look bud..im fucking punk rock..fix the shit or i'll mosh on your face.

lol...huh?

unwrittenLaw

10-29-2003, 06:25 AM

update:

I went to Mazda and told them to "fix the shit or i'll mosh on your face"..but no luck.

unwrittenLaw

11-13-2003, 02:15 AM

another update:

I was driving on the freeway for a couple hours, and all of the sudden when I went into wot, the boost on my Blitz TT started increasing....its like all of the sudden, the MBC started to work...maybe something was clogged in the vacuum lines and the high pressure from a lot of freeway driving forced it out..I really have no idea.

Anyway, I adjusted the mbc to spike at around 10 and level off at around 8. I did notice that I could still hear faint metallic rattling when it was under full load in 4/5th gear, even with the colder NGK spark plugs. It's not consistent and only seem to be audible around 10psi and higher. But since I've lowered it to 8 I sometimes hear rattling, but I don't know if its detonation or not. I'm paranoid and thought the colder copper plugs would help....It might not even be detonation, maybe the heatshield or wastegate was rattling or something...I dunno. But now that I've turned down the boost some it doesnt happen, so I'm assuming its detonation....I wish I could know for sure whats going on in there, but I should assume the worst and be cautious. I just don't get how a lot of people are boosting so high w/o out any major mods and dont hear any knocking, etc...and then sometimes detonation isnt even audible...

505zoom

11-13-2003, 02:23 AM

Crazy:eek: All that nothing for weeks and then the boost just decided to come on??? Was it noticeably faster or was there maybe just something wrong with your TT???

unwrittenLaw

11-13-2003, 02:43 AM

No the boost guage on the Blitz TT is accurate, and yes my car was noticeably faster when it started boosting more. It was a cool night out and I was doing about 75 when I floored it in 5th gear...it felt like I downshifted to 4th...although its fun..I know my engine wont last long doing that all the time, thats when it would ping, so had to turn it down some..

unwrittenLaw

11-24-2003, 03:42 AM

Does anyone else notice any different noises when running higher boost? It seems sometimes I hear slight rattling noises when its boosting....I'm not sure if its detonation or not, but I think if it was and I've been hearing it this long, my engine would have blown by now...so I'm thinking it's the heatshield, or wastegate or something...

any suggestions?

II-Savy

11-24-2003, 01:25 PM

What octain gas are you using?

dj JINX

11-24-2003, 03:30 PM

I took my joe p mbc off once and reinstalled it a day later. I tried to adjust the mbc and redo the lines after i couldnt get the boost past stock. I couldnt figure it out why no boost past stock. Then i realized i was turning the knob the wrong way. lol

1sty

11-24-2003, 03:39 PM

Try welding the waste gate shut (thumb)

unwrittenLaw

11-24-2003, 06:00 PM

Great idea 1st..!!, I'm gonna go do that right now....then I'm gonna punch myself in the face. :)

unwrittenLaw

11-24-2003, 06:01 PM

Originally posted by II-Savy
What octain gas are you using?

Mobil or Shell 91 Octane...all we can get out here in Cali is crappy 91..

1sty

11-24-2003, 06:02 PM

Originally posted by unwrittenLaw
Great idea 1st..!!, I'm gonna go do that right now....then I'm gonna punch myself in the face. :)

Punch me while your at it :D

unwrittenLaw

12-01-2003, 08:02 PM

Update:

Today when I got in my car and started driving, I noticed on my boost gauge that the car is at stock boost again. I checked the MBC, vacum lines, etc...readjusted the MBC, and it stays at stock boost like it was doing before. The boost holds steady but its not where it was at the day before.. WTF is going on? This is really frustrating. How can it go from not boosting above 6-7psi, then all the sudden go up to 9-10...now back to stock? Is Joe P's MBC defective? I have another MBC i could try, but i put it in there before when i was having this problem, and it didnt let me increase boost either. I mean what else could it be? The MBC is connected in line w/ the WG and the T fitting to the bpv.....I dunno what's happening....Someone help me before I go insane.

Notorious

12-01-2003, 08:14 PM

Thats a lot of work. I recommend unplugging the wastegate line for monster power!

Originally posted by 1st MP3 in NH
Try welding the waste gate shut (thumb)

unwrittenLaw

12-01-2003, 08:54 PM

Notorious

12-01-2003, 09:37 PM

unwritten come out to the next meet at least that way we could all try to fix the problem. 8 stumped heads are better than 1.

unwrittenLaw

12-03-2003, 02:12 AM

yeah, i've been trying to get out to one of the meets...when and where is it again?

Notorious

12-03-2003, 10:25 AM

currently we just kind of meet up randomly or go to life in LA. PM me your number and I'll let you know whats going on.

unwrittenLaw

12-03-2003, 06:00 PM

It probably wouldn't be able to go if its all the way up in LA, but if its local I might be able to...

GAspeedProtege

02-12-2004, 02:08 PM

I'm also having this problem now. I just installed my JoeP and I have been turning it like he said, but there has been no steady increase. By that I mean that I would turn it and I would hit 7-8psi. Then I'd get out and adjust it and I'd be at stock boost again, and I am turning it the right way!

unwrittenLaw

02-12-2004, 03:21 PM

I took out the mbc and had the dealer replace all the vacuum lines...but I haven't put the mbc back in...probably wont...i'd rather be able to punch it and not worry about boost, than have to be constantly checking my gauge and making sure i dont go into wot in 4th or 5th..etc, etc...

GAspeedProtege

02-12-2004, 04:08 PM

Just to make sure, the bottom outlet on the MBC is connected to the stock T fitting and the side outlet is connected to the line that goes straight to the wastegate, right?

unwrittenLaw

03-12-2004, 02:06 PM

Well I decided to put back in my joep mbc. What a pain in the ass. I had the dealer replace the vacuum lines awhile back, so I pulled back the foam to check them out, and they used the same crappy hard rubber lines like before. So I cut a piece off to put in the mbc but there was barely any slack on the line to the wastegate. Then when i started pushing the mbc into the line, it just kept splitting. Then I wanted to just replace the whole wastegate line with a better hose, but after removing some intercooler piping, i still couldn't reach it. So I finally cut some more off of the crappy hose and got the mbc in there. So I put everything back together and go driving...AND STILL CAN'T GET HIGHER BOOST...WTF!! I checked and checked everything and I just dont get it. I've even tried different mbc's and nothing. I have the screw almost all the way down and its like its not even there...its like its just passing the same amount of air through it. But now I can't take it out because the wastegate line that the dealer put in is so damn short that I cant reach it back to the stock T fitting, so I need the mbc in there. This sucks. Can I just get a 1/8 extending piece, not a T, but just something to add line to to reach back to the T fitting?
This is sad.

funnylittlman

03-12-2004, 02:29 PM

I guess your car doesn't want to go any faster unwritten law :(

unwrittenLaw

03-12-2004, 02:35 PM

Yeah its just another thing that's been pissing me off lately about the car...I mean I love it, but sometimes I wanna bitch slap it.

unwrittenLaw

03-14-2004, 06:20 PM

Is it hard to replace the wastegate vacuum line? I wonder if there's something wrong with the actuator or something...

GAspeedProtege

03-14-2004, 08:42 PM

Yup its a bitch

unwrittenLaw

03-15-2004, 12:53 PM

How did you get down there to reach it..

unwrittenLaw

03-19-2004, 12:08 PM

bump

jersey_emt

03-19-2004, 12:11 PM

Taking off the turbo->IC pipe gives you a lot more room to reach the connector. You could also remove part of the intake as well.

GI-

03-19-2004, 12:15 PM

Is it hard to replace the wastegate vacuum line? I wonder if there's something wrong with the actuator or something...
The wastegate vacuum line is a BITCH to get at (unless you have the arms and hands of a 4 year old)!!!!! Here is what you might want to do, just cut that line as close to the wastegate as you can reach leaving at least an inch or so, get an in-line coupler, and upgrade the vacuum line after the coupler. Make sure that is you do this, to lube the coupler or vacuum hose on both ends, to assist in getting the line over the coupler without splitting it.

unwrittenLaw

03-19-2004, 12:34 PM

thanks for the info..what size coupler should i get? i was thinking of getting different sizes from the stock ones so I can try and fit a different MBC that has a larger diameter than the JoeP MBC..

spooling

03-19-2004, 01:11 PM

there are vacuum line connectors that you can use to extend the lines. i would just take the time and pull off the piping and replace the whole line with hoses from kragen. what part of diego are you in?

unwrittenLaw

03-19-2004, 01:12 PM

poway

unwrittenLaw

03-27-2004, 08:16 PM

well i replaced the wastegate line, checked all connections on the other vacuum lines, etc...and put in a different mbc and set the screw. but of course, i still can't get it past 7psi...this is really getting rediculous...

did the dealer secretly install some type of boost control solenoid or valve or something when they replaced my vacuum lines..i know thats a conspiracy theory, but hey..i'm all out of ideas...:(

unwrittenLaw

03-27-2004, 09:10 PM

i think i'm gonna push my car off a cliff

GAspeedProtege

03-28-2004, 01:23 PM

tighten the screw all the way down and SLOWLY go through the powerband building boost. If that doesnt work, i dunno? It worked for me hehe.

unwrittenLaw

03-30-2004, 02:59 PM

i'll try that to see if it does anything, but the screw is already tightened a lot...

TX Speed Demon

03-30-2004, 03:44 PM

Damn dude that sucks. I know how you feel.

I've been driving around in my car unable to make fast right hand turns for the last eight months since my accident last August. When I got my car back from the dealer who did the repairs they told me this was due to slight frame damage. It only acted this way when I drove too fast and only in right hand turns so I assumed they knew what they were talking about and were right. It was extremly depressing, driving the twisties is the main reason I bought this car. It got so bad I purposfully took this car instead of my old SUV when going out to bad areas of town in the hopes it would get stolen. I even started looking at replacing it with an EVO even though I know I can't afford a larger payment.

Then, about 2 weeks ago I rotated my tires and found out the dumbasses at the dealer didn't properly rebolt my control arm to the subframe. There was no nut, and the bolt was sticking out about 2 inches. I bolted it back up and the car is driving good as new now. So keep your head up and keep plugging away at finding the problem. You'll get the solution sooner or later.

GAspeedProtege

03-30-2004, 04:14 PM

switch the lines also.

unwrittenLaw

03-30-2004, 06:03 PM

yeah i've switched lines, switched MBC's, etc...

unless the 2 totally different MBC's are defective, i don't know what else it could be...

GAspeedProtege

03-30-2004, 06:38 PM

Hmmm, take your mbc off, its a JoeP right? Put your mouth over the bottom inlet on the mbc. Cover the tiny hole above the side inlet, and blow in as you tighten the screw. If you never see a difference in the air flowing through it then the mbc is the cause, if not wait till you can barely blow through it and toss it back on. At that setting you should be close to 10, just take it slowly through the powerband in third gear, and see where you are at.

unwrittenLaw

03-30-2004, 07:38 PM

I blew through the Joe P mbc and it seems ok, and I also checked the other mbc that I have in right now...but no luck...

unwrittenLaw

03-31-2004, 03:35 PM

maybe i do have 2 faulty MBC's....anyone have a cheap MBC they wanna sell?

GAspeedProtege

03-31-2004, 04:02 PM

Did you put the joep back on?

unwrittenLaw

03-31-2004, 04:10 PM

numerous times...lol

Emode

03-31-2004, 04:16 PM

id say unplug the wastgate line completely, from the vacuum source on top of manifold. if it builds past 7 psi, then the probs somewhere in the line, or wastegate. If it still holds at 7, then the problem is somewhere else. Your engine should be fine as long as you back off after you hit like 10psi or so.

unwrittenLaw

03-31-2004, 04:27 PM

maybe i'll try that, sounds a little scary though..
so just unplug the wastegate line from the T that goes to the intake and bypass valve?

Emode

03-31-2004, 04:30 PM

maybe i'll try that, sounds a little scary though..
so just unplug the wastegate line from the T that goes to the intake and bypass valve?
unplug then plug it up with something
and once you see it going over 7 start backing off
I cant beleive yoiu still have this problem, this threads been around forever:(

unwrittenLaw

03-31-2004, 04:33 PM

i know..it is sad, and its not like i can go to the dealer and be like "why the hell isn't my car boosting more!"

Emode

03-31-2004, 04:35 PM

yes the catch 22 of mazda warranty
goodluck

TX Speed Demon

03-31-2004, 04:37 PM

Maybe you should take it to a tuner shop. If your in SoCal there has to be shops around that have the knowledge to figure out the problem for you. And you wouldn't have to worry about warrenty with them.

unwrittenLaw

03-31-2004, 04:45 PM

yeah i might try and find a shop..i just feel dumb not being able to resolve this

Dr.Sound

03-31-2004, 05:00 PM

damn dude, over 6 months now......
if u're coming to protegefest we can try different boost controllers.
i have joeP that i know works, a buddy of mine has a brand new joeP.

then there are people that run other mbc's that we can try.