Yes it is.

I'm getting the same DV dumping on part throttle, also hesitation/jerkiness on part throttle - iffy acceleration/loss of power etc.

I know I have a 17705 code, and a CEL (which has reappeared since taking it to Skoda). Just working out which bits to do first in the long line of fault finding for this fault code :(.

I changed the DV for a Forge unit too - and the dumping on part throttle is more noticeable as it's more audible.

Will watch this thread with interest.

is the N249 valve easy to get to (to replace) and is there a prt number or somewhere online I can order a new one?

sorry to be a spaz, but what's the N249 again?

Sometimes when I pull away i get that drain pipe noise, then you can hear the DV operating and a sudden drop in power. Thats at very low revs. Then i change to second and all is well. Sounds like we have the same problem.

What's on the other end of that vacuum hose coming out of the top of the DV??

It must be incorrectly creating a vacuum and opening the valve under certain conditions..... to state the obvious!!

N249 valve activates the Dump Valve.

is the N249 valve easy to get to (to replace) and is there a prt number or somewhere online I can order a new one?

It is a bit of a struggle to get to but See this thread for the part number. http://www.briskoda.net/forums/octavia-i/n249-location-diagram-please/87754/

If you do decide to get one please tell us all if it makes a difference

It is a bit of a struggle to get to but See this thread for the part number. http://www.briskoda.net/forums/octavia-i/n249-location-diagram-please/87754/

If you do decide to get one please tell us all if it makes a difference

Thanks! Will report back, just another thing on my shopping list on 17705 fault fixes

You wouldn't happen to know how much these valves are?

I don't know the exact price but it should be around £52 according to the cupra site.

cripes - really? Best get saving a few more pennies then

cheers

sorry to be a spaz, but what's the N249 again?

Sometimes when I pull away i get that drain pipe noise, then you can hear the DV operating and a sudden drop in power. Thats at very low revs. Then i change to second and all is well. Sounds like we have the same problem.

What's on the other end of that vacuum hose coming out of the top of the DV??

It must be incorrectly creating a vacuum and opening the valve under certain conditions..... to state the obvious!!

Those are my exact symptoms Bodge. Thought it was just me and was difficult to explain. I was thinking of changing the N249 myself too. Don.t know if it's the same for you but if i disconnect the vac hose from the dump valve there is a vacuum there even with the car just idleing. I know when i hear the DV operate at about 1800RPM it's like someone has tied the car to a lampost. Throws me forward in the seat. Also have noticed when it doesn't happen, i have loads more power.

I know when i hear the DV operate at about 1800RPM it's like someone has tied the car to a lampost. Throws me forward in the seat. Also have noticed when it doesn't happen, i have loads more power.

Yep that's exactly what I get.

I haven't tried disconnecting the vacuum hose yet, but im guessing we need to find what's wrongly causing the vacuum and replace it.

I also only get this sometimes.

I feel it's the route of the 17705 problem. We might be getting closer to a fix slowly but surely...........

You tried replacing that valve jobber yet?

Yep that's exactly what I get.

I haven't tried disconnecting the vacuum hose yet, but im guessing we need to find what's wrongly causing the vacuum and replace it.

I also only get this sometimes.

I feel it's the route of the 17705 problem. We might be getting closer to a fix slowly but surely...........

You tried replacing that valve jobber yet?

Hi Bodge,

Just plugged in my VAG COM and i have 17705 listed too. Also it says it's running rich. Just picked up a new turbo pressure hose so may try that first. Then the N249. But i'm determined to get this resolved.

Hi Bodge,

Just plugged in my VAG COM and i have 17705 listed too. Also it says it's running rich. Just picked up a new turbo pressure hose so may try that first. Then the N249. But i'm determined to get this resolved.

Yeah I'm with you on that one. Gotta source the fault.

All i have is the 17705 code currently. From reading what people have tried I've discovered the following:

Cleaning the throttle body doesn't fix it.

Replacing the DV doesnt fix it.

It's not a hose leaking between the turbo and intake manifold (people have replaced all hoses and the code remains, and i've inspected my intake hoses).

Since the power drop/early dump problem only happens some of the time it makes me think it's not a leak, but a sticky valve or actuator of some sort.

Also since the code reads 'pressure drop between turbo and intake' im thinking your right that its the DV being prematurely opened, causing the leak and the strange noise.

I'm thinking i could clear the code, and clamp the vacuum hose on the top of the DV so it cant suck, and take it for a drive to see if the code stays gone. Is it the vacuum hose that activates the DV or the pressure difference between either side of the compressor?

I think I'm gonna get a new N249. If that doesnt work I'm going to replace all the little valves and thingies that could be actuating the DV.

The turbo is wastegated, so running without a DV shouldn't cause any problems should it??

scoobydoobry,

look at this thread:

http://briskoda.net/forums/octavia-i/17705-fault-good-start-new-year/97723/3/

If your saying that the vacuum hose on the DV is sucking at idle, even when the engine is hot, then the N249 is selecting the wrong vacuum source (vacuum reservoir).

It must be a confused/damaged/worn/nakkered N249 at fault.

Surely????

The thread also say the problem was fixed by changing the map.

Just got a price of £45.79 plus VAT from my local Skoda garage for the N249.

Ouch!

Oh and I meant look at what i wrote in that thread, and check that seatcupra.net link. Some useful knowledge in there.

I'm slowly learning about all the funny little bits on my engine that don't need to be there, but are!!

I don't have a remap, so it's not that.

What about having a Revo trial on your car and see how it goes after that?

Just got a price of £45.79 plus VAT from my local Skoda garage for the N249.

Ouch!

Oh and I meant look at what i wrote in that thread, and check that seatcupra.net link. Some useful knowledge in there.

I'm slowly learning about all the funny little bits on my engine that don't need to be there, but are!!

I don't have a remap, so it's not that.

Hi Bodge,

Been reading all the links from the threads related to this problem and it does look like the DV is throwing a bit of a fit. I have read that a remap sorts the problem or that attaching th DV to the FPR line does that too....hmmmm. I had my car booked in at Performance Torque on 15th March for a remap anyway so may give that a go if i cannot find a fix.

I did find a diagram for the whole boost system, valves pipes and all but i've lost the link. Only have the print out. If i find it again i'll post it.

Yep that's exactly what I get.

I haven't tried disconnecting the vacuum hose yet, but im guessing we need to find what's wrongly causing the vacuum and replace it.

I also only get this sometimes.

I feel it's the route of the 17705 problem. We might be getting closer to a fix slowly but surely...........

You tried replacing that valve jobber yet?

Just to say that is exactly my symptoms! The whole being thrown forward thing, massive stuttering! :( Most of the time the car is jerky, boost levels are up and down, but Monday the car for the whole 30 mile journey to work and back felt as though the turbo was non existent - you could hear the suction/DV dumping but it felt as if there was absolutely no boost at all (and at the same time, no stuttering!!)

Well as an update - and having being peeved driving it all this time I've bought the following (picking it all up tomorrow) having read many threads here and on a Cupra site for 17705 cures.

028 129 748 - Throttle Body Gasket (for cleaning the throttle body)

078 906 283 A - N249 Valve

06A 145 790 C - Pressure Hose (Turbo to I/C)

058 133 753 B - Suction Pump

035 103 245 A - PCV Valve

06A 103 221 BR - 3 Way Breather Hose

3metres of of different ID Vacuum Hoses

Also

Forge Turbo Intake Pipe

N75j Valve

NGK Iridium Spark Plugs (for good measure)

Lastly

Full licensed VAGCOM from RossTech

I will make it my mission to get to the bottom of this blasted problem!! It is literally driving me nuts.

That lot should sort it !

lol - hope so!

Although i bet it cost a small fortune !

Wow! Sounds like you have a busy weekend of car fiddling ahead of you!

Let us know how it goes...

I would reccommend testing the car between each major change, so you can find what it was and reduce the chance of picking up any more problems. Like between plug change, N249 change and N75J change maybe. Depends how your doing for time really though i guess.

I've done my plugs, so it wasn't that for me. My money is on the N249. Go on, try it first for me and test it!!!!

If you find what the problem is you will be hailed a hero! If it doesnt go then blame the codding ECU!

If it doesnt work..

Box of matches, gallon of petrol !

lmao!! don't tempt me!

Yeah did cost a pretty penny :eek:, but I will crack on with the N249 first - I have a gut feeling it's DV related, and I've changed the OE DV for a Forge so it isn't that.

I will report back rest assured!