mk4 ibiza cupra VAG-COM Logs - Boost issues

[Pabs]

i'm gonna check it when i've got some time - but can't do a proper clean as don't have a new gasket or anything yet. Might add it to the to-do list - but doubt this would be the cause - this is not really stuttering/hesitation - I get the boost i need initially and strongly - and then it disappears almost instantly, then comes back about a second later, drops again.. and so on until it just seems to clear itself.

 

[Pabs]

Possible fix has been found... certainly improved things! Need to do a bit more work to see if I can get it perfect, but will update when I have more info!

 

[Damoegan]

Sounds promising, Pual. Fingers crossed

 

[Damoegan]

Some good info on the N75 valve here, Paul http://forums.vwvortex.com/zerothread?id=2666114#30501513

 

[paddy26]

Any updates?

 

[Pabs]

nothing yet I'm afraid.

 

[Pabs]

Ok, well to bump up an old thread of mine, this is starting to annoy me again now

Not sure if it is worse because of the extreme cold weather, or just my imagination, but the boost issues are back big-time

Has anyone else had this before, and solved it? Please don't mention the map being a possible fault, as I'm sure this has got worse recently - and previous owner said he never had the problem, so I'm suspecting it's a component/pipe or something that has split and is getting worse over time.

N75 replacement obviously didn't resolve issue.
I've bypassed the N249 etc - didn't help.
I've unplugged MAF - issue still exists.

Could it be a collapsing TIP? What hoses or solenoids, other than the N75/N249 etc are involved in regulating the boost?

Thanks

 

[Damoegan]

What about a dodgey actuator, Paul?

 

[Pabs]

Possibly - how would I be able to test/confirm this though?

 

[Damoegan]

I think you attatch a pump with a gauge to the actuator vac line and see what pressure it opens at. Dont hold me to it though..

Might be worth asking Bill.

 

[Pabs]

Is it easy to get to/adjust? I don't want to mess around with something i don't understand.

ahh. yeah, saw a video on google about that. I wouldn't know what pressure it SHOULD open at etc.. might be best leaving it to JKM to look at.

 

[Pabs]

I'm going to try doing some more datalogging when I get chance, and if my laptop battery lasts long enough! lol

Going to log 114 and 115 and check req vs actual again, and this should hopefully highlight that the car isn't making requested boost... I just don't know where I'd go from there. Will try and also log 118 for N75 duty cycle.