HELP with my 1.8 t

[caddy]

Hi can anyone help me ive got 2000 mk4 golf gti 1.8t.  150bhp  Sometimes it boost and then it doesnt boost i have changed coil pack, diverter valve, n75 valve, i have checked pipes best i can as i havent got an air line. when i put new n75 valve on could hear swerling noise so put old one back on and no swerling noise but what ever i do still no boost properly didnt think it would be boost leak as still have boost that works when it wants but im new to turbo cars please can anyone help

[caddy]

got code p1287 turbo bypass valve open where is it   

[barrym381]

Delete it then see if it comes back 

[caddy]

do you know where it is. my car gone slow

[Mr_Orange]

do you know where it is. my car gone slow

Delete the fault code.....

Sounds like you have access to a code reader?

[caddy]

i have delete it so many times it comes back so there must be a problem

[lemski]

Id have thought its refering to the n75 or recerc valve.
What id do if it was mine is replace vac pipes with silicone and delete things that arnt need. Leaves you sith 4 vac lines.
If youve tried a n75 id see if you can get hold of a recerc valve to try

[caddy]

am new to turbo cars :nerd:i put new n75 on now i can hear the turbo more but still the same was going to get new dv today to see if that helps.am not sure what pipes your talking about what i should changes.thanks for helping with this

[itavaltalainen]

Log measuring blocks to see when (under what conditions) you get issue that throws fault code.

[Wazzzer]

Test the N75, one pipe you should be able to blow straight through the other should be blocked.

I presume being a 2000 car yours is AGU? If so there's not a great deal that can go wrong on them to cause fault codes, wiring to the N75 is always worth a check