Boost spike problem, with video..(fixed page3)

[r8byb]

No it doesnt log, just fault codes i think.

Is 22 psi just a light load then ? as my guesimates were a bit off, it only does it if i go flat to the floor in a a higher gear at 1.8k rpm ish, anything above 2.3k rpm it spikes at 22 ish and pulls all the way through.

 

[ChrisCurzon]

Sounds similar on the video to my problem, i've been told that mines a boost leak, but yet to find it
Get some logs done and then can see what your boost is requesting

 

[r8byb]

Got any video's of yours Boris ? what i find wierd is its peaking fine, its on the way back down it does it, like ti will peak at 26psi, then when it gets too 23psi, it will make that noise etc..

Rob.

 

[ChrisCurzon]

No ain't got a video but will try and get one later.
Mines when its leading up to full boost

 

[r8byb]

Oh right, mine smooth as you like as you can see from the video when the boost is building up, it peaks and it does it just when it starts coming back down.

 

[ibizacupra]

No it doesnt log, just fault codes i think.

Is 22 psi just a light load then ? as my guesimates were a bit off, it only does it if i go flat to the floor in a a higher gear at 1.8k rpm ish, anything above 2.3k rpm it spikes at 22 ish and pulls all the way through.

you will see %load on vagcom.
block 115 request vs actual boost

 

[B3NPM_Cupra]

i really think its overboosting due to the extreme cold as its nothin like when i replaced the n75 when i had the car.

 

[r8byb]

Still no vagcom , i can confirm this only happens in 3rd or 4th, had it spiking to 24psi and holding for a little in 5th tonight, and doesnt do it in 1st or second, if i can get my revo turned down from boost 9 what would roughly be 22psi ? about boost 7 ?

 

[rhysox]

i had the 'brrrrr' sound last night that you were describing r8byb.. i've got a forge tip so the spool is louder, i can hear it spooling, it comes on boost, no idea at what psi as I don't have a boost gauge, then it would just be rapid for a few seconds, torque steer etc... then it would fall over, limp mode. No lights or anything- just no boost at all. After a few seconds it would come back on boost. SO annoying. According to computer- 2.5 degrees outside. But it used to happen in 10-20 degrees in summer.

So annoying!

 

[r8byb]

I see, no idea what it is then ? My mate and a few others seem to think it could be a coilpack/spark plug.

You have the exact same noise in my video then ?

Anyone else got any input on whether it could be coil or plugs causing this, hopefulyl have vagcom next week.

 

[rhysox]

well, this weekend im changing n75, plugs, coilpack and MAF... then it's being serviced- just to be sure! (It's due a service anyway)

I'll be so annoyed if it's the same afterward haha!!

 

[longman]

I have worked on an RS4 with this problem before too. That was also remapped.

It would pull really well but once it had spooled up, it would do just the same, it didn't go into limp mode but it would back off a bit and judder. (Nothing to do with traction control in this instance either)

When I looked at the boost curve, you could see it spooling up and then it would spike and then fluctuate.

He got the boost turned down in the end and its fine now.

 

[r8byb]

Well let me know how you get on, You going to change one at a time then try it ? so you know the problem ?

My mate reckons the spark is burning out at high boost causing the brrr brrr noise

 

[rhysox]

Well this is the thing- everything part wise could be ok... i think the actuator has been fiddled with by someone in their garage or something (previous owner), and instead of researching the tuning on them just had a fiddle instead. That's why i'm taking it to a vw/audi specialist asap to see exactly whats been modified!

 

[r8byb]

Ok, just count the threads on the actuator, should be 13 i think, i counted mine yesterday and its standard.

 

[PhilW]

Rhys, i'll check yours out for you.

Sounds like a coilpack/spark plug timing issue to me tho.

 

[rhysox]

yeh will do! hopefully its just something simple like that! do you have to see it from under the car?

 

[rhysox]

Thanks Phil, i'm not very technically minded with these 1.8T's

 

[r8byb]

Was that aimed at me Phil being spark plugs/coil or Rhy's sorry ?

Rob

 

[PhilW]

Both, a brrrr on full boost then limp sounds like a firing problem somewhere to me, but i cant really say without driving it etc..