MK5 Golf GTI

All Things Mk5 => Mk5 General Area => Topic started by: DomBacon on December 21, 2014, 10:22:26 pm

Title: loosing boost without any leaks
Post by: DomBacon on December 21, 2014, 10:22:26 pm
Running Stage 2 revo map on my edition 30. Since i've gone stage 2 i seem to be loosing boost. it hits 19psi and drops to around 12/13psi.
Plugged it into vag.com and nothing came up. Smoke tested the intake system, intercooler, dv and also got the garage midnight pcv king and everything holds 50psi with no leaks.

Been like this for a few months now and still cant find the leak anywhere!

A few people have told me it could be the map, anyone else had this problem?

If so i'll be looking at going either goapr or rtech depending on peoples reviews

If anyone can help that would be great  :happy2:

Cheers Dom.
Title: Re: loosing boost without any leaks
Post by: rich83 on December 21, 2014, 11:21:20 pm
19 PSI sounds about right... stage 2 revo usually peaks about 1.3-1.4 bar.
Title: Re: loosing boost without any leaks
Post by: DomBacon on December 21, 2014, 11:46:08 pm
19 PSI sounds about right... stage 2 revo usually peaks about 1.3-1.4 bar.

It doesn't hold like it used to
It hits 19psi for like 0.1 second and drops to 13/14 psi
Title: Re: loosing boost without any leaks
Post by: th3_f15t on December 22, 2014, 09:57:13 am
Generic answer time: Checked the usual areas of weakness, such as the DV, PCV and HPFP cam follower? Also, have you run a full diagnostics with VCDS or similar?

Although your DV could of been fine before a tune up, it could of since started failing hence the loss of power in recent times. Good service practise on tuned up TSFI engines is to check it regularly as well as other suspect areas.
Title: Re: loosing boost without any leaks
Post by: DomBacon on December 22, 2014, 11:03:14 am
Generic answer time: Checked the usual areas of weakness, such as the DV, PCV and HPFP cam follower? Also, have you run a full diagnostics with VCDS or similar?

Although your DV could of been fine before a tune up, it could of since started failing hence the loss of power in recent times. Good service practise on tuned up TSFI engines is to check it regularly as well as other suspect areas.

Full diagnostics has been done about 10 times, pcv replaced for new one, dv replace with a new forge one.
Haven't checked the HPFP cam follower yet though, would that make a massive difference??
Title: Re: loosing boost without any leaks
Post by: th3_f15t on December 22, 2014, 11:07:34 am
If it's failing, yes. I would replace it ASAP if you've not already, as if it fails you could be up for a very nasty sized repair bill.

http://www.awesomegti.com/car/vw/golfmk5/2-0tfsi-cam-follower-replacement-kit - Parts needed.

There's a few how to guides on here, about 30 minute job from start to finish. :happy2:
Title: Re: loosing boost without any leaks
Post by: fab5freddy on December 22, 2014, 10:09:45 pm
Have you tried the N75? Mine was sticking and didn't show up any fault codes, was causing massive surge, and like you would peak then drop off
Title: Re: loosing boost without any leaks
Post by: DomBacon on December 22, 2014, 10:43:04 pm
If it's failing, yes. I would replace it ASAP if you've not already, as if it fails you could be up for a very nasty sized repair bill.

http://www.awesomegti.com/car/vw/golfmk5/2-0tfsi-cam-follower-replacement-kit - Parts needed.

There's a few how to guides on here, about 30 minute job from start to finish. :happy2:

Ok thanks a lot! How would I know it's failing though?
Title: Re: loosing boost without any leaks
Post by: DomBacon on December 22, 2014, 10:44:24 pm
Have you tried the N75? Mine was sticking and didn't show up any fault codes, was causing massive surge, and like you would peak then drop off

Not yet as the car still runs fine! :/
Title: Re: loosing boost without any leaks
Post by: bacillus on December 22, 2014, 11:55:46 pm
With issues like this you'll need to resort to live logging data as an auto scan may not yield any fault codes.
Title: Re: loosing boost without any leaks
Post by: infernalant on December 23, 2014, 08:29:56 am
If it's failing, yes. I would replace it ASAP if you've not already, as if it fails you could be up for a very nasty sized repair bill.

http://www.awesomegti.com/car/vw/golfmk5/2-0tfsi-cam-follower-replacement-kit - Parts needed.

There's a few how to guides on here, about 30 minute job from start to finish. :happy2:

Thanks for the link, Im assuming this is suitable for all GTI engine types? mines a 55 plate axx

Title: Re: loosing boost without any leaks
Post by: th3_f15t on December 23, 2014, 09:13:10 am
As far as I'm aware, it's suitable for all 2.0 litre TSFI engines (Golfs, A3/S3 & Leons).
Title: Re: loosing boost without any leaks
Post by: DomBacon on December 23, 2014, 11:53:54 am
With issues like this you'll need to resort to live logging data as an auto scan may not yield any fault codes.

How would I do that?
Title: Re: loosing boost without any leaks
Post by: th3_f15t on December 23, 2014, 12:06:43 pm
VCDS is the top diagnostic tool to use, but it's pricey and you'll need a laptop to install it onto. An alternative for logging a bit of info is a Foxwell NT-500 which is what I went for, not as advanced but costs half as much and you don't need to lug a laptop around with you.
Title: Re: loosing boost without any leaks
Post by: GrayMK5GTI on December 23, 2014, 12:07:58 pm
With issues like this you'll need to resort to live logging data as an auto scan may not yield any fault codes.

How would I do that?

Follow the guide in here:

http://www.goapr.co.uk/support/datalogging.php