very strange i DON'T have a cel!

[meaty101]

5 days into owning my lovely tfsi vrs and it's an absolute pleasure driving this car. But we're not totally problem free unfortunately.  Now to be honest comparing the power to my Leon fr with the same engine the Octavia feels way down on power. Picks up higher up in the rev range but through the mid range it's poor. No cel light on but found a code for evap sysem incorrect flow or something like that. Replaced the N80 purge valve cleared the fault, hasn't come back so it appears I've sorted that. So, pcv seems ok no lumpiness very smooth idle, plugs, filter recently changed, coil packs not too sure but no misfires, i unplugged the maf sensor just to see if it improved but it didn't. I do have a new G version diverter valve which I'm fitting tomorrow. One thing did baffle me though. When i unplugged the maf and ran the car the engine management light didn't pop on. The code/fault was there when i re scanned. What's going on there?

Edited 30 April, 2017 by meaty101

[KenONeill]

Maps sometimes throw spurious CELs, so I guess some 'sole has mapped out the CEL or removed its bulb.

[Guest]

From experience on an PD105, when I disconnected the MAF connection with the ignition off for testing, the CEL did not illuminate on a run.

However when disconnected while the engine was running I did get a message on the maxidot. This extinguished after cycling the ignition.

Seems it doesn't flag as faulty unless it happens whilst running.

[mikey vrs]

Does the engine management light come on when you turn on the ignition? Or has it been removed? 

Edited 25 November, 2016 by mikey vrs

[meaty101]

Yes the light is still working it was the first thing i checked for when i viewed the car. Its quite an old trick!! I did take the car for a 3 mile drive with the maf unplugged. No lights popped up at all but the fault was there when i scanned.

[RichieXR2]

I ran my old vrs mafless for a few weeks and it didn't illuminate the CEL, I cannot remember if it threw up a code but the car ran as normal with it unplugged.

Does the car feel different between "mapped" and "unmapped"? Have you measured the boost pressure?

[meaty101]

No no boost tests i wouldn't know where to start with that!! Just backside dyno tells me it isn't pulling as hard as it should. The maf unplugged made no difference at all so that rules that out i think. Onto the diverter valve tomorrow. I will update my findings.

[meaty101]

On 11/25/2016 at 21:21, RichieXR2 said:

 

Edited 30 April, 2017 by meaty101

[RichieXR2]

When my D.V failed I had normal boost up to about 3k and then it sounded like a dump of boost pressure similar to when the valve opens but obviously longer.

The valves can fail in other ways though.

To check boost you would need to access live data on whatever diagnostic device you are using.

[meaty101]

It's hard to explain what the car is like. It initially feels a bit like limp mode but you can slightly hear the turbo spooling up, but your waiting waiting for the power to kick in but it never comes. It does accelerate but the car is nowhere near what it should be. I know this as i just sold a Seat Leon FR last week that had the same tfsi motor. That car went very well so I've been fortunate I've had something to compare it with. If I'd bought the Octavia without owning the Leon first i might just have thought it was normal because it's still nippy!!

[meaty101]

Right people i have some news. Swapped the diverter valve today. The old one was a C version couldn't find a production date on it but chances are it's the original one. All looked well tbh, no rips or tears in the diaphragm it looked in very good condition. So as i had a new G version i fitted it anyway. Took the car for a run and it did feel a bit better low down the rev range but still not right. So, maybe 4 or 5 miles what a shock. Turning left at a T junction foot down in second gear and off the car went pulled hard right through honestly the car is a revelation.  it's took me a week but i finally have the car i thought i was buying all along. I'm presuming with the car losing boost it's took a few miles for the ecu to learn new boost levels. As for the d/v, i can only think it's either failed internally which is unlikely or the spring has weakened over the years. So no split rubber diaphragm but that's been my issue.

Edited 30 April, 2017 by meaty101

[RichieXR2]

Glad you got it all sorted mate! Enjoy your new found power!

[meaty101]

Glad you got it all sorted mate! Enjoy your new found power!

Thanks. it's going well so that's been the issue. I hope it helps someone. Just a visual check of the d/v didn't show anything it looked in good condition.

[Lozb]

On 25/11/2016 at 14:53, meaty101 said:

5 days into owning my lovely tfsi vrs and it's an absolute pleasure driving this car. But we're not totally problem free unfortunately.  Now to be honest comparing the power to my Leon fr with the same engine the Octavia feels way down on power. Picks up higher up in the rev range but through the mid range it's poor. No cel light on but found a code for evap sysem incorrect flow or something like that. Replaced the N80 purge valve cleared the fault, hasn't come back so it appears I've sorted that. So, pcv seems ok no lumpiness very smooth idle, plugs, filter recently changed, coil packs not too sure but no misfires, i unplugged the maf sensor just to see if it improved but it didn't. I do have a new G version diverter valve which I'm fitting tomorrow. One thing did baffle me though. When i unplugged the maf and ran the car the engine management light didn't pop on. The code/fault was there when i re scanned. What's going on there?

 

Do you mind if I ask where you got your N 80 purge valve from and at what cost.  Was it an easy job to swap? Mine is noisy but I'm struggling to source a reasonably priced replacement this side of China. 

[meaty101]

I bought mine from TPS ( trade parts specialists ). Roughly £40 iir. I'll find the receipt tomorrow with price and p/n. I did see them on eBay for half the price if you don't mind a wait. As an update on that issue though, eventually that fault came back. I then bought a new charcoal canister which sorted it eventually. Changing both the valve and canister is very easy. The only tricky part is breaking the vag clips off the inlet and outlet pipes to and from. Remember you'll need a couple of jubilee clips before breaking them. It may have been possible to get at it without removing the air filter box ( tfsi engine ) but I never tried it.