There is a long thread on P1031 and this post will answer your question.

I also logged Block 142, fields 5 & 6 are the flap data in this extract..

Andy - Thanks so much for this. really helpful

I just went on with OBDeleven and monitored the whole block on channel 142 - could clearly see that the flap adaption was ok, and could see the called vs actual position of the flaps was working correctly.

plotted a really quick chart in the live data, showing how you can see it moving pretty much instantaneously to setpoints when I'm taking the rev range over around 3200 rpm and back down again.


Added piece of mind that the system is working as intended! It's so smooth now I guess sometimes you can question if they're moving at all!

Thanks again ?
It's so good to have an FSI thread that's positive, rather than the usual doom and gloom.
A positive approach, with the intention to achieve a successful end. There's no reason why an FSI will not respond to the same method as any other (lesser) engine.
Sorry if I come over as a bit restrained, but didn't want to go over the top.
Mac ?
Amazing thread, one of the best I've read. I'm sure all fsi owners will be delighted with the inspirational restoration. Must be amazing to get an engine so old working so well. Hats off ?
Thanks - Yep its a good feeling to get it working well again. The car has done over 150,000 miles so I'm hardly chasing the last 3 horsepower - its just good to have at least the first 3 feeling really strong!!! Hopefully it'll carry on for many more miles....
It's so good to have an FSI thread that's positive, rather than the usual doom and gloom.
A positive approach, with the intention to achieve a successful end. There's no reason why an FSI will not respond to the same method as any other (lesser) engine.
Sorry if I come over as a bit restrained, but didn't want to go over the top.
Mac ?
Cheers and absolutely - The new valves have definitely had a big part to play in rolling back a few years & getting performance closer to where it should be.

However (and I understand this isn't practical for everyone), if we really look into what I've done with the exception of the above, basically ive just stripped the top end down and given it a thorough cleaning. the build up of years of detritus is the root of all evil with these (and I guess any other engine, especially w/direct injection). So just undo some bolts, clean it up and put it back together. Its definitely doable for any DIY mechanic/enthusiast. ?
As a fellow FSi owner, I can only doff my cap to you sir, it is indeed one of the best threads I have read and watched in pictoral form! Very very impressive, and I can only agree with @PlasticMac about the need for a positive thread on the fsi rather than the usual slating!
keep up the good work, and a beer is in order when this is finished...
As others have said, a fantastic thread this and all credit to Yellow_Peril for something this in depth which was almost a norm 40 years ago which used to be called a top end decoke. Naturally a lot harder to do with the complexities and lack of working space in the A2 but Just goes to show what a determined mind and some skills is able to achieve. As a fellow FSI owner i know all to well what fantastic cars these are when they're running right, well done sir.
Very well done indeed! A call to Infinity exhausts is probably not a bad move. Well regarded on here,

All the very best, and hope to meet up at some point at one of our socials.
Hi all, all going well - 7000 miles since rebuild. Car is now actually for sale in the classifieds here. not advertised anywhere else just yet as id like it to stay in the community. I'd love to keep it but I need a tow car for another project and I don't have the space for them all.

For Sale

First job was to attempt to see why/how the timing belt failed in the first place, and if the engine was seized or failed terminally.

after fully removing the upper timing belt cover and inspecting with a torch... I found the water pump pulley had completely sheared off.... Never seen anything like it!

View attachment 91623

The engine could be turned over extremely carefully, manually until interference from valves was felt. so as the bottom end was free, me and a couple of friends attempted to strip the car down and get into repairing it.

So - bit of a hit list to work from, which was added to as the car was stripped.
  • Replace Timing Belts & water pump
  • Check intake manifold and flaps for signs of coking
  • Remove & assess damage to head
  • Check condition of water tree, coolant system and "death pipe"
  • Investigate misfire issue
So using a common sense approach, along with some of the resources/ links to manuals on here we set at removing the old timing belt assy, intake/exhaust manifold and head. this has been pretty well documented on here before, so I won't tread old ground apart from saying you absolutely do need to remove the left engine mount and lower the engine on a jack a little to give enough clearance to remove the intake manifold. You just cant get your hands in otherwise, or clear the bulkhead/scuttle.

What I will say is if you're a competent DIY mechanic its all completely doable, don't be put off. there's not a lot of space, but all in all it took around 4.5 hours to strip the head out of the car at the first attempt,

...And here are the findings!

8 off very bent exhaust valves. One very coked up combustion chamber & head

View attachment 91621

if anyone is in any doubt, this is not what an exhaust valve should look like ?;

View attachment 91629

Also, due to the sheer amount of carbon deposited on the inlet valves, as I'm this far it'd be silly to not replace these too. There's just no way these were sealing correctly and would have been contributing to the common FSI problems;

View attachment 91630

One very coked up intake manifold/ports - showing that after any amount of previous work, when a car recirculates exhaust gasses it will foul up again. This one operated fine, and wasn't sticking, however this was the amount of carbon build up after approximately 40,000 miles, despite only being ran exclusively on Shell V Power and having regular servicing.

View attachment 91626View attachment 91627

Right so, root cause of the timing belt failure.

Upper tensioner had completely seized, causing the belt to jam, and shearing the water pump pulley off.

The car had been sat for the last couple of years without much running, I think potentially accelerating failure. Couldn't be helped, Just really unlucky and one of those things...

On the positive side - This car has already had a large amount of the cooling system replaced, including the death pipe. it all looked pretty much brand new, no signs of leaking so thought best to leave in situ and not disturb any of it. could find myself chasing my tail and end up replacing the lot otherwise. also, no damage to pistons or cylinder bores. looks like I got away without a catastrophe.

Due to the amount of coking and the FSI being a direct injection engine, I made the decision to fully rebuild the head and while the injectors were out, have them refurbished/cleaned. With all of the above I thought the car would have half a chance of a clean bill of health. and with a rebuilt head - Give it a real new lease of life.

Next step.... order parts and start the clean up and rebuild.
I feel for you Yellow_Peril, I too am in a similar situation.. pump on right (pic 2) is for comparison.
New (comline) w/pump lasted 3000 miles.., all tensioners, etc.. all ok, I,m wondering if mine was caused by Evans Waterless Coolant..


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