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25det Wastegate Issues

chur

By chur,
in Engines & Forced Induction

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chur Rookie

chur

Posted
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how odd..

So, just to get this right, the waste gate is wired so the flapper is in the open postition..

Then there should be no way that thing should be climbing in boost pressure reguardless of where u get the signal from.

arrghh.. question,

can the wastegate actually 'open' all the way? I mean is it only opening say half way or two thirds?

Are you sure there is nothing in the wastegate dump pipe that is blocking gas flow?

well thats all i got! not much help huh?

Yup I know what your saying, the flapper was definetily wired fully open, infact further than the actuator would normally throw it.

Hmm I had the dump pipe completely out of the car the other day all seemed to be in order, maybe I will need to dig deeper.

I know it sounds impossible, seems impossible to me too :worship:

chur Rookie

chur

Posted
  • Author
Posted
if the wastegate and actuator are working fine, why not look at other possibilities?

haha i was about to suggest boost controller but u said u dont have one.

i would check vacuum lines and pretty much anything looking for any leaks splits or anything like that.

but hey im no expert.

Cheers lineskee

Na your right, I need to start again at the basics, thanks for your input

Cubes Grand Master

Cubes

Posted
Posted

Its quite possible the motor is breathing a little better due to the recent inlet mods. That paired with the stock dump that definitely favours turbine flow rather than wastegate flow 'could' tip it over the edge of boost creep.

I'd almost be inclined to again flick that circlip from the wastegate/actuator arm, disconnect it and wire the flap open again.

It just can't/shouldn't over boost with the wastegate wired open.

All bets are still on the stock dump and combination of inlet/breathing mods. :worship:

The problem I have though is a cat back with stock dump/front and fmic is quite a common mod, others don't see boost creep problems, so why do you? :S

chur Rookie

chur

Posted
  • Author
Posted
Its quite possible the motor is breathing a little better due to the recent inlet mods. That paired with the stock dump that definitely favours turbine flow rather than wastegate flow 'could' tip it over the edge of boost creep.

I'd almost be inclined to again flick that circlip from the wastegate/actuator arm, disconnect it and wire the flap open again.

It just can't/shouldn't over boost with the wastegate wired open.

All bets are still on the stock dump and combination of inlet/breathing mods. :mellow:

The problem I have though is a cat back with stock dump/front and fmic is quite a common mod, others don't see boost creep problems, so why do you? :S

Its cause I'm special :worship:

I'll take it for a longer squirt with the wastegate wired open tomorrow, I agree it should be impossible!

thanks

13thracer Rising Star

13thracer

Posted
Posted

my old post for your same issue may help, the problem would come and go for me but in the end with the stock 25 in it, it was the intercooler piping causing my issue.

maybe you are special like i was, the previous motor in it was meant to be a 25 until it went bang and when i pulled it down found it had 26 internals with massive cams hence the too munch exhaust flow out of a stock 25 turbo. id be hoping to be special :)

http://www.skylinesaustralia.com/forums/in...=133869&hl=

zebra Grand Master

zebra

Posted
Posted

no dramas mate....

where abouts are you getting the reading for the boost gauge?

is it off the IC piping or the manifold?

was thinking along the lines of what has been said previously about the tight bends in the piping, so if your are getting your Gauge feed from the IC piping maybe its blocked and backing up before it gets to the manifold.

Does the car go like shit off a slippery shovel when on boost or is it unresponsive and....well...slow?

GT

chur Rookie

chur

Posted
  • Author
Posted
my old post for your same issue may help, the problem would come and go for me but in the end with the stock 25 in it, it was the intercooler piping causing my issue.

maybe you are special like i was, the previous motor in it was meant to be a 25 until it went bang and when i pulled it down found it had 26 internals with massive cams hence the too munch exhaust flow out of a stock 25 turbo. id be hoping to be special :cool:

http://www.skylinesaustralia.com/forums/in...=133869&hl=

13thracer thanks for the link it got me thinking, went to the garage in anger determend not to sleep till I found the problem coz it just didn't add up.

Then it dawned on me that the idiot who assured me that the pod filter would flow more than enough air for my application may have been talking out of the wrong hole. Set the wastegate up as it should be,Yanked the poddy off and in a fit of foot stomping anger wheeled out of the garage, freaken thing is holding boost perfectly!!!

Somehow I new this problem was going to end up making me look like a total tool :( my experience with cars is that 90% of the time it's something simple.

Bad news is it probably doesnt have super awsome internals, damn it!

Thanks for all the advice guys

WogsRus Veteran

WogsRus

Posted
Posted

OK so i can't be bothered reading the post, drunk an all, but i had a problem with my stock turbo, in that it would bost creep, no matter what, so i took it off, and bored the gate out and the surrounding inlet, no more issues now. LOVE IT.

chur Rookie

chur

Posted
  • Author
Posted
no dramas mate....

where abouts are you getting the reading for the boost gauge?

is it off the IC piping or the manifold?

was thinking along the lines of what has been said previously about the tight bends in the piping, so if your are getting your Gauge feed from the IC piping maybe its blocked and backing up before it gets to the manifold.

Does the car go like shit off a slippery shovel when on boost or is it unresponsive and....well...slow?

GT

Thanks brother it turned out to be the pod filter without it, it holds boost perfectly... I still would have expected different symptoms but I guess if your not learning then your probably dead!

The guy that sold me the filter(and specifically assured me it would flow enough) is going to get a kick in the nads. :(

Cheers for your time

MANWHORE Grand Master

MANWHORE

Posted
Posted

The pod filter wouldn't cause your boost to go up to infiniti. Something is at play here.

With my stock turbo, it held boost perfectly. I had all of the usual gay stuff like ic, exhaust, pod, blah blah blah.

With just the actuator connected, it would hold 5 psi. with the normal dual boost thing, it woudl do about 9 psi after all those other mods. never higher.

Somethign is definitely at play there. It's impossible if the flapper is wired open for it to still go to crazy boost. If you knwo someone that knows a bit about turbos, get them to take a look at it.

A pod won't do shit in terms of affecting boost.

13thracer Rising Star

13thracer

Posted
Posted

out of interest does the pod have the top of it sort of blanked off (no air goes in the top just the sides) like you i had pod issues too with the crapy K&N have a look at the apexi power intake take a good look at the diagram on the box or on the web, of how the air enters the pod and how it goes into the AFM it creats less turbulance with air flow. i noticed it drove and went smoother after fitting a apexi than the K&N which when in comparison was just nasty, try a power intake and you will be pleasatly suprised.

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