MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: bellios on November 26, 2013, 11:09:03 am

Title: rear PCV and running a boost test
Post by: bellios on November 26, 2013, 11:09:03 am

hi guys,

is there a definitve way of testing whether your rear PCV is bad? Ive got the revo revamp kit for the front PCV, but still seem to be suffering from inconsistent boost.

Idles fine, and when i pull the dipstick it bogs as expected.

also has anyone used a pressure tester, and if so did you block anything off prior to running some pressure into the turbo inlet?

really getting annoyed with this now as ive already replaced plugs, coilpacks, rev g diverter, revo front pcv revamp and a load of other stuff to try and remedy this problem.

Not getting any errors in VCDS so im guessing ive got a split hose somewhere.

thanks for any help!

Title: Re: rear PCV and running a boost test
Post by: 56OctyVRS on November 26, 2013, 11:45:32 am

It might be more cost effective to take it to a specialist with a rolling road and get some live data to see what the engine is doing under load. Also I'd consider fitting the latest PCV rather than a revamp.

Title: Re: rear PCV and running a boost test
Post by: bellios on November 26, 2013, 12:02:08 pm

it had the latest PCV fitted about 6 months ago. the problem started with this part fitted and there was no change after the PCV revamp went on there.

Id like to try and run a boost test before going to a specialist as i have checked preety much everything else. Im reluctant to pay someone for doing what im doing at the moment - ive never been that blown away by the service ive had at the specialists local to me. Shame AKS or MRC arent a bit closer by!

Title: Re: rear PCV and running a boost test
Post by: 56OctyVRS on November 27, 2013, 10:29:06 am

Is the car standard or mapped?

Title: Re: rear PCV and running a boost test
Post by: bellios on November 27, 2013, 10:44:46 am

stage 1 map mate.

Ran a leak test last night anyway. Managed to block off both PCV breathers and get a testing kit onto the turbo inlet pipe. no blatant leaks which is frustrating. May have to suck this up and get it booked into a specialists shortly as im out of ideas :D

Title: Re: rear PCV and running a boost test
Post by: 56OctyVRS on November 28, 2013, 07:59:53 am

It could be a faulty n75 valve but you ideally need to see what the ecu is requesting and what the engine sensors are actually reading. This would help understand what is going on and pinpoint the problem area and save you wasting anymore money better spent on other things this time of year

Title: Re: rear PCV and running a boost test
Post by: GLIDN on November 30, 2013, 12:19:48 pm

I had inconsistent boost as well.
To a point where I would have no boost what so ever.

Replaced the Airflow sensor, front PCV, tried another FSI (stock intake)
Still ad the problem. Replaced my N75 a few days ago.
Now a nice and healthy rock solid steady 21.8psi pressure.