what is it?!?! boost playing up

[nick s]

i know there a few questions like this already at the mo, but my cars booked into jabba on monday and i dont know if this is anything serious. car boosts fine 99% of the time but there are certain scenarios when it goes funny.

a) if i come out of a corner fast in any gear at above say 4000rpm, the car will come on and off of boost through the rest of the gears

b) if i am holding it a certain revs waiting for the car in front to move over. i.e 4000rpm it will then go funny.

what could it be? i thought it might be heatsoak but now i have a forge FMIC. i thought it could be the dumpvalve sticking but it only does it at funny times i.e out of corners at high revs. i thought it could be the MAF but why wouldn;t it do it any other time? anyone got any ideas? anyone else experience this? will they be able to diganose it at jabba?!

 

[Barry.L]

i would assume that jabba will vagcom the car first before loading the new map, so this will tell you what the problem is. it will probably be one of the usual suspects ie, n75, knackerd DV, ect.

 

[nick s]

the thing is, i've only had the DV on there for about 3 weeks?! brand spanking new forge one.

do Jabba stock spare parts like n75, MAF etc incase of things like this?

 

[Barry.L]

well it almost certainly wont be the dv then. jabba work on 1.8T engines all the time, so they must stock the relevent replacement parts that commonly cause problems or at least order them in. as with most boost problems though its hard to tell until you vagcom the car.

 

[p34ch3y]

i also have this very same problem

 

[nick s]

odd isn't it?! does yours do it the same time as mine?!

 

[p34ch3y]

yea pritty much m8, sometimes when i go to boot it on the boost gauge it just sits there at 20VAC ish then shoots up all of a sudden

 

[acidstrato]

fellas logs using vagcom is the only way to diagnose problems you speak off

second guessing is worthless and you could be checking things over and over

 

[PhilW]

Sticky DV. Check its nice and lubed up and the piston moves freely.

Are you goin round the corners with your TCS on?

 

[p34ch3y]

yes and no ,,,,,,,it happens when i go for it in a strate line n all

 

[PhilW]

Check your DV and the hose off the top of it.


Then check the N75.

 

[nick s]

ahh phil, youi could be onto something. the hose in top of my DV is not held on eith a jubilee clip anymore. it moves pretty freely. could this be causing it?! i'll put one on it at the weekend!

 

[PhilW]

If its the shitty braided rubbish just replace it completely.


Check your DV as well.

 

[acidstrato]

with the dv only being a few weeks old i cant see it being the problem