peak boost judder..

[dellenty69]

last few days i have had a slight issue with my car when boosting hard, as soon as i get around 15psi it will judder like mad, boosting up to that its fine.

so...
checked for codes.. nothing
replaced my n75 went from a H to an E (E is the new F)...nothing
maf isnt very old, 6months or so, but i removed it and cleaned it....nothing

coil packs are fine, and so are spark plugs. as far as i can see anyway.

tank is full of high octain fuel now, (last week i put normal stuff in as garage diddnt have any) i have run redex fuel cleaner, and a octane booster...week on and nothing. i have used 95ron fuel before with no problems.

so i have run out of ideas. all boost hoses are good, pcv all good.


give me some ideas people...

thanks in advance
james

[alexd]

Checked for fuelling issues? blocked fliters and the rest of it?

[daz veedub]

overboost ?

[dellenty69]

no i havent checked the fuel filter, but my plugs are the correct colour, and im not getting any fuel bank lean or anything, and its only on hard acceleration.

could be worth replacing the fuel filter, where abouts is it on these?


no not over boost, mine is stage one mapped, so 19psi is peak and it holds 18psi, then tails off to 15. plus its just had a new n75 valve.

[alexd]

Well on my AUQ i THINK it is on the left hand side of engine bay next to washer bottle, but i havn't ever really looked, i know my car hesitated when it was old, and that it was fine after they changed it in a service, so never having had to change it myself i don't know where it is, but like i say it fixed similar symptons on my 1.8T. 

[Rhyso]

Fuel filter is under the car towards the rear.  You're on about the charcoal canister which is next to your washer bottle 

Diesels have the fuel filter in the engine bay 

[rio_gti]

Fuel filter is under the car towards the rear.  You're on about the charcoal canister which is next to your washer bottle 

Diesels have the fuel filter in the engine bay 

hey rhyso, can you tell me what this does..... dont laugh either!!!!   :embarassed:

[Rhyso]

Fuel filter is under the car towards the rear.  You're on about the charcoal canister which is next to your washer bottle 

Diesels have the fuel filter in the engine bay 

hey rhyso, can you tell me what this does..... dont laugh either!!!!   :embarassed:

Not 100% tbh - think its something to do with the emissions control.  I stand to be corrected.  Petrol engines are not my forte

[Wazzzer]

for once, you're right 

[Rhyso]

for once, you're right 

First time for everything huh