boost problem

rogerstrampoline · 23-07-2012, 03:31 PM

So I installed a boost controller (not a tee) and turned the gate all the way anti clockwise for lowest setting and its still spiking at load in 3,4,5 and hitting 14psi.....do u reckon it will be a leak or a wastegate problem? I've checked all clamps etc on wastegate lines....

project.r.racing · 23-07-2012, 03:51 PM

what do you mean 'spiking'?

rogerstrampoline · 23-07-2012, 04:00 PM

Well I want it to only run 10psi because I'm getting boost creep on cold nights which is leading to boost cut when I plant it

so a mate gave me a brand new boost controller so i wanted to turn it down and stop it from creeping but it didn't work....should I check the line for cracks or splits?

project.r.racing · 23-07-2012, 04:03 PM

you shouldn't bee hitting 10psi on a stock setup. something is not releasing pressure.

rogerstrampoline · 23-07-2012, 04:07 PM

It's not stock...its got a fmic and custom piping with a monza ssq blow off valve that vents to atmosphere. So doesnt have factory piping or bov

maztech · 23-07-2012, 04:21 PM

Change the Monza BOV

rogerstrampoline · 23-07-2012, 04:24 PM

You reckon get a turbosmart one?

BG1.8sp · 23-07-2012, 04:31 PM

What boost controller? What have you set the duty cycle to??
This will create high spikes.

And are you sure it wasn't spiking before the boost controller?

Also look for any pinched boost hoses. If one is bent past 90drgrees or folded or pinched it can have this effect

derb · 23-07-2012, 04:31 PM

Can't be the BOV can it? That would only show up if he got off the throttle. Sounds like the wastegate on the turbo isn't opening right.

BG1.8sp · 23-07-2012, 04:32 PM

Good example... Brothers Evo spiking to 28 psi instead of the 22psi that is was supposed to be running at. Was caused by the boost like to be slightly squished under the battery tray.

BG1.8sp · 23-07-2012, 04:34 PM

Also I have never ever seen a BOV causing boost spikes... EVER! lol
A leaking BOV will massively reduce boost and wouldn't even let it spike.

There isn't any need for a BOV anyway... So if you think that's the issue (guarantee it's not) then take it out an block the openings

rogerstrampoline · 23-07-2012, 04:39 PM

It was spiking before the boost controller went in...thats why I put it in

BG1.8sp · 23-07-2012, 04:53 PM

If it was spiking... Then a boost controller will never solve the issue. Replace all vaccuume lines. Would be recommended... But number one priority would be to pull the waste hate actuator lines. Symptoms of a restrictor/ welding tip wedged into the waste gate line.
Common JDM technique of upping the boost and it's completely unnoticeable

maztech · 23-07-2012, 04:54 PM

Quote:

Originally Posted by BG1.8sp

Also I have never ever seen a BOV causing boost spikes... EVER! lol
A leaking BOV will massively reduce boost and wouldn't even let it spike.

There isn't any need for a BOV anyway... So if you think that's the issue (guarantee it's not) then take it out an block the openings

Funny that I have seen it before on a BOV not operating correctly -- But anyway -- Example the factory Bosch ones you find around had a faulty batch causing spike

rogerstrampoline · 23-07-2012, 04:56 PM

I'll try that this weekend then

thought it might be a wastegate issue that its not letting out enough pressure but wasnt sure....cheers guys ill see how I go

maztech · 23-07-2012, 06:04 PM

Don't pull the lines off and drive it the waste gate won't open at all causing full boost pressure , anyway if you pull the wastegate line watch ya boost gauge. Last thing you want to do is boom , you still need to take this car to a Dyno for mixtures on boost

BG1.8sp · 23-07-2012, 06:07 PM

Lol I didn't mean drive it

Replace it!!

BG1.8sp · 23-07-2012, 06:09 PM

As I said... Common to wedge welding tips into waste gate actuator lines.
This reduces the airflow and increases boost. Vaccuume hose is ultra cheap... And it's probably an old hose on there anyway... So replace it and inspect old one for reducer.

TheMAN · 23-07-2012, 06:58 PM

boost controllers cannot decrease boost, it only can increase it!
the wastegate actuator is preset to open at a certain boost level based on the length of the rod connecting to the wastegate... some wastegate actuators are adjustable, and you can adjust the length to set the boost level.... this is the lowest full boost pressure your car will go... so in otherwords, setting the dial to "0" on your boost controller is practically not having the boost controller at all... from there, it is all mechanical (from the wastegate actuator)

as others said, you need to check for obstructions in the boost signal line between the wastegate actuator and your vacuum source

also a larger intercooler, freer flowing exhaust contributes to boost creep, which also can cause boost spikes in cold weather... it depends on the size of your turbo and size of intercooler/exhaust

you also need to make sure the wastegate actuator can move freely... if there is something caught in the way or it is not moving smoothly, the wastegate won't open properly and cause high boost pressures... you need to blow into the hose connecting to the wastegate actuator and watch if the wastegate actuator moves... do not try to move it by hand, there is too much spring tension and you might break the diaphragm inside!

rodhog · 23-07-2012, 11:05 PM

WEll As above - you need to work out if it's waste gate issue - simple just plum it right into it. And see what your base boost is. Shoudl be around 7psi on BPT. peck at 8-9.

All small turbos will spike.

To get more control out of a boost controller. Non electric - even electric sometimes.

YOu might need to run an olive. - OR a small brass peice you fit before the controller to reduce to airpressure to a level is can bleed off.

From factory all mazda's with electronic control boost had them. Of course during the years owners removed for either more boost or for flatter boost curves depending on model car . Hole sizes varied from 0.7mm to 1.2mm.

I've normally used a 1mm hole in a bit of solid plastic brass or what ever fits into the hose.

This normally gives you enough contorl back. Normally your turbosmart or EBC has one built into it but normally it's just a bit big for some of the older model cars and wastegates.

I found it always on KE's and Mx6's-- TX-5 and S4/5 Turbo RX-s'
along with some skylines they would spike very hard.

23-07-2012, 03:31 PM	#1
rogerstrampoline AstinaGT Regular Join Date: Apr 2012 Location: south brisbane Car: 1993 BG Astina SP Posts: 365 View Photos By: rogerstrampoline	boost problem So I installed a boost controller (not a tee) and turned the gate all the way anti clockwise for lowest setting and its still spiking at load in 3,4,5 and hitting 14psi.....do u reckon it will be a leak or a wastegate problem? I've checked all clamps etc on wastegate lines....

23-07-2012, 04:31 PM	#8
BG1.8sp Senior Member Join Date: Jul 2008 Location: Sydney Car: 2009 BL MPS Posts: 2,300 View Photos By: BG1.8sp	What boost controller? What have you set the duty cycle to?? This will create high spikes. And are you sure it wasn't spiking before the boost controller? Also look for any pinched boost hoses. If one is bent past 90drgrees or folded or pinched it can have this effect __________________

23-07-2012, 04:31 PM	#9
derb Senior Member Join Date: Oct 2008 Location: Brisbane Car: 1993 BG Astina GT-X Posts: 1,822 View Photos By: derb	Can't be the BOV can it? That would only show up if he got off the throttle. Sounds like the wastegate on the turbo isn't opening right. __________________ 1993 BG Astina 'GT-X'

23-07-2012, 04:32 PM	#10
BG1.8sp Senior Member Join Date: Jul 2008 Location: Sydney Car: 2009 BL MPS Posts: 2,300 View Photos By: BG1.8sp	Good example... Brothers Evo spiking to 28 psi instead of the 22psi that is was supposed to be running at. Was caused by the boost like to be slightly squished under the battery tray. __________________

23-07-2012, 04:34 PM	#11
BG1.8sp Senior Member Join Date: Jul 2008 Location: Sydney Car: 2009 BL MPS Posts: 2,300 View Photos By: BG1.8sp	Also I have never ever seen a BOV causing boost spikes... EVER! lol A leaking BOV will massively reduce boost and wouldn't even let it spike. There isn't any need for a BOV anyway... So if you think that's the issue (guarantee it's not) then take it out an block the openings __________________

23-07-2012, 03:51 PM	#2
project.r.racing Senior Member Join Date: Sep 2004 Location: n/a Car: n/a Posts: 10,929	what do you mean 'spiking'?

23-07-2012, 04:00 PM	#3
rogerstrampoline AstinaGT Regular Join Date: Apr 2012 Location: south brisbane Car: 1993 BG Astina SP Posts: 365 View Photos By: rogerstrampoline	Well I want it to only run 10psi because I'm getting boost creep on cold nights which is leading to boost cut when I plant it so a mate gave me a brand new boost controller so i wanted to turn it down and stop it from creeping but it didn't work....should I check the line for cracks or splits?

23-07-2012, 04:03 PM	#4
project.r.racing Senior Member Join Date: Sep 2004 Location: n/a Car: n/a Posts: 10,929	you shouldn't bee hitting 10psi on a stock setup. something is not releasing pressure.

23-07-2012, 04:07 PM	#5
rogerstrampoline AstinaGT Regular Join Date: Apr 2012 Location: south brisbane Car: 1993 BG Astina SP Posts: 365 View Photos By: rogerstrampoline	It's not stock...its got a fmic and custom piping with a monza ssq blow off valve that vents to atmosphere. So doesnt have factory piping or bov

23-07-2012, 04:21 PM	#6
maztech Senior Member Join Date: Aug 2009 Location: QLD Car: ...... Posts: 952	Change the Monza BOV

23-07-2012, 04:24 PM	#7
rogerstrampoline AstinaGT Regular Join Date: Apr 2012 Location: south brisbane Car: 1993 BG Astina SP Posts: 365 View Photos By: rogerstrampoline	You reckon get a turbosmart one?

23-07-2012, 04:39 PM	#12
rogerstrampoline AstinaGT Regular Join Date: Apr 2012 Location: south brisbane Car: 1993 BG Astina SP Posts: 365 View Photos By: rogerstrampoline	It was spiking before the boost controller went in...thats why I put it in

23-07-2012, 04:53 PM	#13
BG1.8sp Senior Member Join Date: Jul 2008 Location: Sydney Car: 2009 BL MPS Posts: 2,300 View Photos By: BG1.8sp	If it was spiking... Then a boost controller will never solve the issue. Replace all vaccuume lines. Would be recommended... But number one priority would be to pull the waste hate actuator lines. Symptoms of a restrictor/ welding tip wedged into the waste gate line. Common JDM technique of upping the boost and it's completely unnoticeable __________________

23-07-2012, 04:56 PM	#15
rogerstrampoline AstinaGT Regular Join Date: Apr 2012 Location: south brisbane Car: 1993 BG Astina SP Posts: 365 View Photos By: rogerstrampoline	I'll try that this weekend then thought it might be a wastegate issue that its not letting out enough pressure but wasnt sure....cheers guys ill see how I go

23-07-2012, 06:04 PM	#16
maztech Senior Member Join Date: Aug 2009 Location: QLD Car: ...... Posts: 952	Don't pull the lines off and drive it the waste gate won't open at all causing full boost pressure , anyway if you pull the wastegate line watch ya boost gauge. Last thing you want to do is boom , you still need to take this car to a Dyno for mixtures on boost

23-07-2012, 06:07 PM	#17
BG1.8sp Senior Member Join Date: Jul 2008 Location: Sydney Car: 2009 BL MPS Posts: 2,300 View Photos By: BG1.8sp	Lol I didn't mean drive it Replace it!! __________________

23-07-2012, 06:09 PM	#18
BG1.8sp Senior Member Join Date: Jul 2008 Location: Sydney Car: 2009 BL MPS Posts: 2,300 View Photos By: BG1.8sp	As I said... Common to wedge welding tips into waste gate actuator lines. This reduces the airflow and increases boost. Vaccuume hose is ultra cheap... And it's probably an old hose on there anyway... So replace it and inspect old one for reducer. __________________

23-07-2012, 06:58 PM	#19
TheMAN Senior Member Join Date: Feb 2010 Location: USA Car: . Posts: 2,623	boost controllers cannot decrease boost, it only can increase it! the wastegate actuator is preset to open at a certain boost level based on the length of the rod connecting to the wastegate... some wastegate actuators are adjustable, and you can adjust the length to set the boost level.... this is the lowest full boost pressure your car will go... so in otherwords, setting the dial to "0" on your boost controller is practically not having the boost controller at all... from there, it is all mechanical (from the wastegate actuator) as others said, you need to check for obstructions in the boost signal line between the wastegate actuator and your vacuum source also a larger intercooler, freer flowing exhaust contributes to boost creep, which also can cause boost spikes in cold weather... it depends on the size of your turbo and size of intercooler/exhaust you also need to make sure the wastegate actuator can move freely... if there is something caught in the way or it is not moving smoothly, the wastegate won't open properly and cause high boost pressures... you need to blow into the hose connecting to the wastegate actuator and watch if the wastegate actuator moves... do not try to move it by hand, there is too much spring tension and you might break the diaphragm inside! __________________ Protege FAQ, the best 323/Protege/Mazda3 resource enjoyed worldwide for 10 years Last edited by TheMAN; 23-07-2012 at 07:00 PM.

23-07-2012, 11:05 PM	#20
rodhog Senior Member Join Date: May 2005 Location: Sydney Lakemba Car: mx-6 626 Gs300 Maz2 was 95 KF BA-HT Posts: 2,024 View Photos By: rodhog	WEll As above - you need to work out if it's waste gate issue - simple just plum it right into it. And see what your base boost is. Shoudl be around 7psi on BPT. peck at 8-9. All small turbos will spike. To get more control out of a boost controller. Non electric - even electric sometimes. YOu might need to run an olive. - OR a small brass peice you fit before the controller to reduce to airpressure to a level is can bleed off. From factory all mazda's with electronic control boost had them. Of course during the years owners removed for either more boost or for flatter boost curves depending on model car . Hole sizes varied from 0.7mm to 1.2mm. I've normally used a 1mm hole in a bit of solid plastic brass or what ever fits into the hose. This normally gives you enough contorl back. Normally your turbosmart or EBC has one built into it but normally it's just a bit big for some of the older model cars and wastegates. I found it always on KE's and Mx6's-- TX-5 and S4/5 Turbo RX-s' along with some skylines they would spike very hard.