Hi, i recently got my Vrs revo'd and its started juddering. Now before you mention coil packs this is what happens:

Driving along in 2nd and acelerate hard from low revs, you can hear the turbo spool up, and just as it gets to about 3000 rpm, i let off the throttle to maintain that speed and it will judder. Its almost like you let off the throttle then quickly put it down and let off again. Really weird

i know!

No warning lights come on, i did have a coil pack die the other day and was hoping that it would have cured it when i got a new one but it hasnt.

Has anyone got any idea what it could be? Its only since ive had it mapped ive noticed it.

Cheers Joe

N75 valve by the sounds of it get vag com on it a check light doesnt always come up

Also, you did get some newer plugs and so on before the remap, right?

Also, you did get some newer plugs and so on before the remap, right?

+1.

Although mappers generally check fuelling and any issues on vagcom prior to mapping the car, anything that is marginal like coilpack, plugs, DV, N75 valve that may be running fine on std map do tend to fail or start playing up after a Map due to the increase in stress on them from upping the performance.

Re run Vagcom on the car to check if anything is flagged since Map.

Ok thanks, how do i run vag com? What does the n75 valve actually do?

N75 is a solenoid for boost control pressure. It operates the actuator on the turbo.

i think your all looking past the basics guys

Do tell...

Ok cheers, sorry about the simple questions, ive spent most of my driving time with jap and french cars! This is the first Vag car ive had!

i think your all looking past the basics guys

Clive please explain so we can all be educated......

Edited 9 January, 201115 yr by Bowders1

Hi mines remapped.ive replaced 3 coils and spark plugs, upgraded Dump valve and cleaned out n75 valve.still judders when idle and seems to misfire when accelerating.

have you cleaned out the throttle body?

Nope, do they normally get contanimated?

yes very, if its dirty it can cause lumpy idle and flat spots. There is a good guide on here for cleaning it.

great cheers

Did it do it before the remap?

I had an APR trial map and it caused the same issues you are having.

Did it do it before the remap?

I had an APR trial map and it caused the same issues you are having.

I've had issues with my Octavia since trying an APR trial map. Not major issues just as described a slight judder.

For me I'll be cleaning the throttle body in two weeks (possibly the first time it's been cleaned in 69k miles) and after that will look at replacing the N75. The plugs and Forge 007P are ok. After that will end up taking it somewhere like R-Tech to get them to have a look.

Didnt have a trial on it. Also Ive heard from a couple of people that have driven it before the remap (people that serviced it, and the guy that mapped it) that its been the nicest octavia they have driven!

It just gets ittitating with this judder!!

Have you checked the breather hoses under the inlet manifold? Mine did the same sort of thing and I found one of the hoses had a 1" split in the side.

Did it idel any different? Mine runs perfect apart from the judder every so often

When you say judder, do you mean the car jerks when you ease off the throttle a bit? Mine did that, and getting a different map sorted it. With the APR map, full throttle was spot on, just a bit rough on part throttle. It seemed to release boost at the wrong time.

Waiting to see what clive says lol.

APR map? Mine does feel a little rough on part throttle. TBH everything seems to be pointing towards the map.

Might try and contact the people who did the remap for me, see what they say....

APR and REVO are connected in someway - APR used to be REVO or vice versa.

Hope you get it sorted anyway.

The idle was normal but when I put my foot down it would boost and sort of judder then boost again. Once I changed the split pipe it was ok.

Edited 21 February, 201115 yr by Nickbes

Ok thanks, ill have a good look about under the bonnet and see what i can find!