MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: jaycue2u on September 12, 2011, 01:55:12 pm

Title: Boost leak
Post by: jaycue2u on September 12, 2011, 01:55:12 pm

As in the post, i seem to have a boost leak. I was driving home this morning and the boost was fine, booted it coming off a round about and the pressure built up then the car seemed to hesitate, it done this a few times and just didnt feel like it was boosting properly  :confused: so i put the windows down and tried again and you could here that everything was spinning up fine, then reached a certain pressure (dont know what pressure as i have no boost guage) and made a whistling noise. It seems pretty consistant and happens only when booted.

Im hoping its something like a pipe clip has came away and the pipe is blowing once it reaches a certain pressure. Does anyone else have any input to this?

The car was Revo'd a month or so ago so im guessing the increase in boost pressure has caused this to fail. I bought it from a trader who has gave me 3 months warrenty on it so it can / will be going back to him, but can he see if the map has been changed?

Thanks in advance

Title: Re: Boost leak
Post by: liver on September 12, 2011, 02:22:24 pm

the first couple of things i would check or want you to confirm are the following;

latest revision diverter valve or uprated
lastest revision pcv fix opr uprated

these are the common boost leak areas, ive had both on my rempped gti

if not then check all joints for hoses etc like you mentioned

Title: Re: Boost leak
Post by: jaycue2u on September 12, 2011, 04:25:59 pm

The car is stock apart from the Revo, i had mentioned to someone that i thought it could be the recirc valce or actuator as this happened on my MR2 tubby when i uprated the boost controller and thus running more boost.

Title: Re: Boost leak
Post by: liver on September 12, 2011, 05:29:42 pm

what age is your car??

Title: Re: Boost leak
Post by: jaycue2u on September 12, 2011, 07:53:04 pm

05 plate

Title: Re: Boost leak
Post by: PDT on September 12, 2011, 08:48:22 pm

Sounds like tne infamous diverter valve.

Title: Re: Boost leak
Post by: jaycue2u on September 12, 2011, 11:11:07 pm

Any idea on the cost of said diverter and a part number / suitable replacement? How do i test to see if this is the issue?

Title: Re: Boost leak
Post by: bacillus on September 12, 2011, 11:28:29 pm

Quote from: jaycue2u on September 12, 2011, 11:11:07 pm

Any idea on the cost of said diverter and a part number / suitable replacement? How do i test to see if this is the issue?

Best way to check your DV is to remove it and look for tears in the diaphragm (assuming you have the old type one).

Part number for the oem revision D one is 06H145710D and costs around £50.

Title: Re: Boost leak
Post by: jaycue2u on September 13, 2011, 10:52:24 am

Does anyone know how to access the DV or have a "how to" guide? The car is off to someone at lunch time and i just want to have something to hand to show him so he can go straight to it without costing any more ££ than need be  :happy2:

Title: Re: Boost leak
Post by: liver on September 13, 2011, 11:07:09 am

there is a guide on here somewhere

check the search function

Title: Re: Boost leak
Post by: jaycue2u on September 15, 2011, 10:51:08 am

Cheers fellas, replaced the DV with the piston type and alls good  :congrats: reasonable tear in the old diaphragm so was reasonably obvious