Author Topic: bosch maf not allowing full boost?  (Read 7003 times)

Offline DarkGti

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Re: bosch maf not allowing full boost?
« Reply #10 on: 21 March 2010, 22:51 »
ive got exactly the same problem, ive had new turbo, new maf, new n75 valve and still im only boosting at 15-18psi think ive got a boost leak somewhere :angry:
yours is an AUM isn't it Ry? maybe worth binning the pcv pipework mine was split on one of those pipes  :sad:

No matt its a AGU  :wink:

Offline Grand Master Patch

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Re: bosch maf not allowing full boost?
« Reply #11 on: 21 March 2010, 22:54 »
ive got exactly the same problem, ive had new turbo, new maf, new n75 valve and still im only boosting at 15-18psi think ive got a boost leak somewhere :angry:
yours is an AUM isn't it Ry? maybe worth binning the pcv pipework mine was split on one of those pipes  :sad:

No matt its a AGU  :wink:

Bin it anyway :wink:

Offline gti_shaun

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Re: bosch maf not allowing full boost?
« Reply #12 on: 22 March 2010, 00:34 »
I know is not a correct or good thing to be doing but if you clamp off the pipe to the actuator it runs full boost with no n75 control, i did this before to make sure my turbo was ok, it went stright upto 21psi maybe a little more so im thinking its ok, has anyone else tried this if so what boost was made(i have ko3s)

Offline gti_shaun

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Re: bosch maf not allowing full boost?
« Reply #13 on: 22 March 2010, 11:29 »
no 0ne done this then to make sure the turbo can produce good boost, just wanted to know it it should have gone higher

Offline DarkGti

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Re: bosch maf not allowing full boost?
« Reply #14 on: 22 March 2010, 11:32 »
didnt even know you could do it tbh will try it out :wink:

Offline G60GTI16V

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Re: bosch maf not allowing full boost?
« Reply #15 on: 22 March 2010, 15:10 »
wont it throw up error codes if u clamp it?

Offline DarkGti

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Re: bosch maf not allowing full boost?
« Reply #16 on: 22 March 2010, 15:41 »
ive got exactly the same problem, ive had new turbo, new maf, new n75 valve and still im only boosting at 15-18psi think ive got a boost leak somewhere :angry:
yours is an AUM isn't it Ry? maybe worth binning the pcv pipework mine was split on one of those pipes  :sad:

No matt its a AGU  :wink:

Bin it anyway :wink:

my sucki meechi(however you spell it) catch can has come today so will be replacing it

Offline topher

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Re: bosch maf not allowing full boost?
« Reply #17 on: 22 March 2010, 16:24 »
i occasionally clamp the n75 on a car to check it can make full boost without ECU control - it's a good test to make sure your turbo can hit full boost but that's all - and you shouldn't leave it like that for more than a 100 yard blast for testing or you risk damaging the turbo and engine. It won't really give you much of an idea as to what is causing the boosting issue (other than eliminating mechanical failure)

Offline DarkGti

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Re: bosch maf not allowing full boost?
« Reply #18 on: 22 March 2010, 23:03 »
right tried the n75 valve clamp and it boosted to 22psi and felt as it did before when i was running 237bhp if not faster, so does this mean i can rule out a boost leak? or does it mean i need the actuator adjusted?
« Last Edit: 22 March 2010, 23:06 by DarkGti »

Offline topher

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Re: bosch maf not allowing full boost?
« Reply #19 on: 22 March 2010, 23:09 »
Seems like it mate. Where did you go the other day anyway i turned around to fetch the smoke tester and you'd disappeared :grin: