MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: cutchie on November 18, 2015, 06:21:51 pm

Title: p0299
Post by: cutchie on November 18, 2015, 06:21:51 pm

So I've had the underboost fault for a wile now replaced the dv pcv and the waste gate actuator, this week I fitted a boost gauge and got the car smoke tested. I'm getting 4 psi and dropping to 3/3.5 and no boost leaks were found anyone any ideas where to go from here?

Title: Re: p0299
Post by: cutchie on November 18, 2015, 06:30:48 pm

Sorry waste gate solenoid**

Title: Re: p0299
Post by: Ricky123 on November 20, 2015, 01:40:16 am

Any mods?
Have you had a scan done with vagcom?

I'd double check all pipes, check intercooler for cracks too.

Title: Re: p0299
Post by: Dan648v on November 20, 2015, 09:33:43 am

Had this code on my gfs a3 tdi and it was the actual actuator at fault. Replaced the unit and boom. Boosting again! Think the diaphragm had split inside?

Title: Re: p0299
Post by: Dan_FR on November 20, 2015, 10:55:51 am

So you've replaced the N75 rather than the actuator? Does sound like the actuator is at fault, not unheard of as mentioned above

Title: Re: p0299
Post by: Dan648v on November 20, 2015, 02:05:42 pm

Take it to a garage and get them to vacuum test the actuator. That'll tell if it's working, that's what my Audi tech did  :happy2:

Title: Re: p0299
Post by: cutchie on December 18, 2015, 12:27:29 am

So thought I would update this I've now replaced the turbo and the fault is Still the same still peaking at 4psi every time anyone any other ideas?

Title: Re: p0299
Post by: Dan_FR on December 18, 2015, 07:49:33 am

4 psi is about actuator pressure when measured at the inlet

Data logging with VCDS is needed need to check all readings and whether the ECU is requesting boost (N75DC% - block 116 from memory - or thereabouts)

Title: Re: p0299
Post by: cutchie on December 18, 2015, 05:12:22 pm

003

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fdaz.co%2Fmedia%2Fl556%2Fcutchie2%2F003.png&hash=fbd672384a8b4a5a4830d913f50ce79b00eeebd7)

114

(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fdaz.co%2Fmedia%2Fl556%2Fcutchie2%2F114.png&hash=1a571eb58f57ebe720aaf18cd1a3b106f0811fec)

115
(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fdaz.co%2Fmedia%2Fl556%2Fcutchie2%2F115.png&hash=96b8fd60f0270d376b78c9404790327110056a22)

Title: Re: p0299
Post by: cutchie on December 18, 2015, 05:13:29 pm

these are the graphs I logged but tbh I don't really know what im looking at or for! lol does anyone else see out anything out of place?

Title: Re: p0299
Post by: Dan_FR on December 18, 2015, 05:54:29 pm

Can you share a link to the CSV files? Are they full throttle runs?

Title: Re: p0299
Post by: cutchie on December 18, 2015, 07:48:06 pm

114
https://docs.google.com/spreadsheets/d/1PTMxiKdea3u4Hk5xOhv54VMDXFdbhSrqKX--NskzNMQ/edit?usp=sharing

115
https://docs.google.com/spreadsheets/d/10l493f3-sEKsM9ZqXpVOucRNd7IjW9-yjBkonb2qLT8/edit?usp=sharing

003
https://docs.google.com/spreadsheets/d/11ASpZUR1Wx3SEpepYzUAtV2AzLGFrtiGMIUAI2hVTuU/edit?usp=sharing

yes all third gear pulls to around 5750 ish
cheers mate

Title: Re: p0299
Post by: Dan_FR on December 19, 2015, 12:36:08 am

Not really helpful as those logs were done separately.

Log these blocks:
114 115 118
001 002 003
031 023 231
091 118 003

So log 3 at a time on each run (press the turbo button), and do a single full throttle run in 4th gear from 2k rpm to as high as possible. Only log this - no other data

Someone else having the same issue on the FB Page TFSI Tuning:
https://www.facebook.com/groups/529405700525327/permalink/723181707814391/