Project FSI - "The Yellow Peril"

[Yellow_Peril]

Afternoon all, after being quiet for a while (I've been busy!!!) I'm starting a project/maintenance & fault finding thread about my FSI - the somewhat aptly named "Yellow Peril" by a friend (You'll find out why soon enough!). ?

Hopefully in time this will add to an already really helpful knowledgebase on A2 ownership you guys have built up on here.

I recently acquired an Imola Yellow CS FSI from here on A2OC - Generally a very tidy and well maintained FSI however I had some bad luck early on....

Initially one of the first things on my list was to carry out a full "piece of mind" service myself & remove the aftermarket Dotz 17 inch wheels - and replace with some pepper pots - What I will say though is on 17's with 215 tyres, there's surprisingly good grip and turn in! Hoping I Don't lose too much in the way of handling moving to 15's and some premium rubber at some point in the future, as the ride is a little too crashy around town... does anyone have any experience of this?

So, I was about to set off to Devon to collect some after agreeing a price, when I got the check engine light & noticed an intermittent hesitation as the swirl flaps opened/closed at between 3&4000rpm (I used to have a DC2 Integra Type R, and and it reminded me of a really poor impersonation of VTEC ??),.... Decided to cancel the 8 hour round trip until my OBD reader arrived to check what codes were active and carry out the service in the meantime.

So... Oil & filter change, fuel filter change, cabin & air filter replaced and 4 new Bosch spark plugs installed. Idle was noticeably better, but fault codes still active (as expected as I had nothing to reset it with until the following day).

I went for an OBDeleven rather than full fat VCDS, no clear reason why, just looked like it'd serve my needs for day to day stuff. Also preferred the live monitoring from smartphone via Bluetooth rather than booting up/carrying around a laptop. Faults were (and I'm sure no surprise to many) -

• P0302 Cyl.2 Misfire Detected - intermittent
• P0300 Random/Multiple Cylinder Misfire - Intermittent
• P1504 Intake air Fault - Intermittent

I have fixes for all of the above - Which I'll get to in a later post.

The car has documented history of the intake manifold being stripped and cleaned previously - so I was hoping I'd have got more than a couple of hundred miles before seeing these types of issues.

However, this was just the tip of the iceberg, as within a mile of my house, the worst happened. Timing belt failure & recovery required. Quick inspection showed that the belts were in good condition (nor were they due for replacement just yet), however the outer belt had completely lost tension.

So, with the above fault codes, and me left wondering the extent of the damage from the failed timing belt (the BAD engine is an interference engine so there WILL be cylinder head/valve damage), I decided to take the car off the road temporarily and attempt to give it a new lease of life, as there aren't many of these on the road anymore.

I'm quite lucky to be handy with a set of spanners and able to draft in a couple of friends for favours so will be attempting all of this from a competent DIY'ers perspective.

Next post will go into the strip down and what I discovered - and a plan of action!

 

[dj_efk]

When it's all done the pepperpots are still here for you Kev!

 

[Yellow_Peril]

So,

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!

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

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

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;

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.

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.

 

[PlasticMac]

Good luck, an FSI in fine fettle is a wonderful thing.
The build up in the inlet manifold, which will, eventually affect the flap mechanism is well known
But, your fault codes indicate that at least (small mercy I know) there's no flap related problems in your engine.
I've always thought any build up in the inlet manifold came from the combination of soot from the EGR, and volatile compounds via the PCV system, which condense on the cooler manifold wall.
I don't see how carbon from the combustion chamber can end on the inside of the inlet manifold. Having had a close encounter with the cylinder head and inlet manifold, what's your thoughts?
Mac.

 

[Yellow_Peril]

Good luck, an FSI in fine fettle is a wonderful thing.
The build up in the inlet manifold, which will, eventually affect the flap mechanism is well known
But, your fault codes indicate that at least (small mercy I know) there's no flap related problems in your engine.
I've always thought any build up in the inlet manifold came from the combination of soot from the EGR, and volatile compounds via the PCV system, which condense on the cooler manifold wall.
I don't see how carbon from the combustion chamber can end on the inside of the inlet manifold. Having had a close encounter with the cylinder head and inlet manifold, what's your thoughts?
Mac.

Im no expert, but I'd say it's ultimately the same thing, as the gasses from the pcv are generally whats blown by the rings from the combustion chamber, along with the EGR - also caused via combustion, so combine those with gradual build up on valve/head port surfaces or anywhere molecules can pass through and eventually it'll end up on all surfaces in the system I guess?

 

[Andrew]

A trivial point. The death pipe is date stamped in the form of a clock face roughly in the middle of the flat face. Stick your phone down the back, take picture and you will have an indication of how old it is allowing two years for it to be in the stock system.

Your dedication to your FSI is off the scale of praise.

Andy

 

[Yellow_Peril]

A trivial point. The death pipe is date stamped in the form of a clock face roughly in the middle of the flat face. Stick your phone down the back, take picture and you will have an indication of how old it is allowing two years for it to be in the stock system.

Your dedication to your FSI is off the scale of praise.

Andy

Awesome, thanks I was trying to find that stamp at the time but missed it - I've got a receipt from 20,000 miles ago though back in 2017, so I was happy to leave it be

 

[A2Steve]

I think the death pipe is only about £10 so if you’ve got the access to change it, I would for piece of mind.

Have you considered removing the flaps from the lower manifold? They are held in with torx screws, 2 per flap. If plan to do it with the next FSI I try to fix.

 

[Yellow_Peril]

I think the death pipe is only about £10 so if you’ve got the access to change it, I would for piece of mind.

Have you considered removing the flaps from the lower manifold? They are held in with torx screws, 2 per flap. If plan to do it with the next FSI I try to fix.

I left the flaps connected and just cleaned carefully with a combination of brushes, the mechanism is operating smoothly.

 

[Yellow_Peril]

Right - on to the fun part - the rebuild!

first job was to fully clean and inspect all the parts removed - I borrowed a friends wash tank for this, which made pretty light work of it all.

luckily the cam followers and camshafts were all in really good condition, boxed these up in the order in which they came off the head, so they'd go back in the same locations later. the valve guides were also luckily in really good condition without any play, and the head wouldn't require skimming.

before and after with the head stripped and cleaned ready for new valves & assembly.

Also - ordered a Victor Reinz full top end rebuild kit - comes with all gaskets, valve stem seals and sealant. Also ordered a set of head bolts, and obviously a full set of valves (but forgot to picture).

Now - with cleaning complete and the head & inlet manifold ready for assembly. lets move onto Injectors.

As I knew I had a misfire on at least Cyl 2 - Thought I may as well have these cleaned and re sealed.

Hurley Race Engineering Carried out the refurb for me. - Will stress at this point I'm not affiliated with them in any monetary way, other than Sean (owner) is a dear friend who builds race engines for a living and has an ANSU injector cleaning machine at his premises.

Really interesting process actually (apologies as ill probably end up dumbing it down somewhat) - The machine fires the injectors simulating engine firing through various throttle loads and engine speeds. After doing an initial test it showed the flow wasn't ideal from any of the 4 injectors, with one in particular (Cyl.2 significantly worse than the others).

The injectors are then put into a cleaning bath and fired to remove any build up of carbon from the combustion chamber and years of detritus from the fuel system. the cleaning solution should be a translucent "ocean blue" - if you look at the injector in the pic below - you can see white calcified deposits working their way out from the injector. This eventually came from all 4 of them after a few cycles in the cleaning bath, turning the solution a murky green colour indicating there was a significant amount of build up on all 4.

After cleaning the test cycle was then completed again. Really good fan pattern - and really pleased to announce I now have 4 injectors firing evenly, and in loose terms - removing the blockages resulted in an approx. 12.5% increase in fuel flow!

I have a slow motion video of the injectors firing, if anyone would like to see? However I cant seem to get it to upload in the post?

After the testing was complete the injectors were treated to new seals - The teflon seals are single use and must be replaced after removing an Injector to ensure correct sealing. We are now ready to go!

Can't thank Sean @ Hurley Race Engineering enough... This will certainly help a way towards the misfire issue, and general efficiency of my FSI.

Again must stress I'm not affiliated financially in any way, just putting a glowing recommendation on here for the work he can carry out if anyone else needs their injectors servicing. Out of respect (and possibly forum rules?!?) I won't add pricing on here - but what I will say is all 4 injectors can be fully refurbished for around the cost of 1 replacement.

Hurley Race Engineering - Web
[email protected]

Now with a clean bill of injector health, a pristine head & lower intake manifold - the new valves were seated and the head was rebuilt.

...Voila!

One head ready to go, save a touch more cleaning - Now time for the big re-assembly job - and fire it up!

 

[dj_efk]

Loving this thread. Well done.

 

[Robin_Cox]

Right - on to the fun part - the rebuild!

first job was to fully clean and inspect all the parts removed - I borrowed a friends wash tank for this, which made pretty light work of it all.

luckily the cam followers and camshafts were all in really good condition, boxed these up in the order in which they came off the head, so they'd go back in the same locations later. the valve guides were also luckily in really good condition without any play, and the head wouldn't require skimming.

before and after with the head stripped and cleaned ready for new valves & assembly.

View attachment 91657
View attachment 91656

Also - ordered a Victor Reinz full top end rebuild kit - comes with all gaskets, valve stem seals and sealant. Also ordered a set of head bolts, and obviously a full set of valves (but forgot to picture).

View attachment 91658

Now - with cleaning complete and the head & inlet manifold ready for assembly. lets move onto Injectors.

As I knew I had a misfire on at least Cyl 2 - Thought I may as well have these cleaned and re sealed.

Hurley Race Engineering Carried out the refurb for me. - Will stress at this point I'm not affiliated with them in any monetary way, other than Sean (owner) is a dear friend who builds race engines for a living and has an ANSU injector cleaning machine at his premises.

Really interesting process actually (apologies as ill probably end up dumbing it down somewhat) - The machine fires the injectors simulating engine firing through various throttle loads and engine speeds. After doing an initial test it showed the flow wasn't ideal from any of the 4 injectors, with one in particular (Cyl.2 significantly worse than the others).

The injectors are then put into a cleaning bath and fired to remove any build up of carbon from the combustion chamber and years of detritus from the fuel system. the cleaning solution should be a translucent "ocean blue" - if you look at the injector in the pic below - you can see white calcified deposits working their way out from the injector. This eventually came from all 4 of them after a few cycles in the cleaning bath, turning the solution a murky green colour indicating there was a significant amount of build up on all 4.

View attachment 91661

After cleaning the test cycle was then completed again. Really good fan pattern - and really pleased to announce I now have 4 injectors firing evenly, and in loose terms - removing the blockages resulted in an approx. 12.5% increase in fuel flow!

I have a slow motion video of the injectors firing, if anyone would like to see? However I cant seem to get it to upload in the post?

View attachment 91660

After the testing was complete the injectors were treated to new seals - The teflon seals are single use and must be replaced after removing an Injector to ensure correct sealing. We are now ready to go!

View attachment 91659

I had this done with a set of injectors for our AUA and it did significantly improve their performance (brought their numbers together comparing before and after) and the way the engine runs overall.

 

[Yellow_Peril]

I had this done with a set of injectors for our AUA and it did significantly improve their performance (brought their numbers together comparing before and after) and the way the engine runs overall.

Makes so much sense to do if its practical to remove them, or if youre doing another job in the same area as I was, especially on a direct injection engine - really glad to hear its worked for you too!

 

[Yellow_Peril]

Loving this thread. Well done.

Thanks - I'm a believer in keeping things going unless its utterly hopeless - and using them! I'm getting quite fond of these little cars, and as there aren't many around anymore - I feel obligated to keep this one going as long as I can ? - although ive genuinely spent more hours underneath/on top of it than inside driving it so far!!!

 

[CrispyEdd]

Wow, excellent thread, this is going to be a great running engine soon. Great work and pictures are excellent. Knowing the right people and places maes it so much easier. Look forward to the finshed build report

 

[simon martyn]

Breathless with admiration, well done Sir!

 

[Yellow_Peril]

Final Assembly.

So - with the car ready for rebuild I went about fitting the new head gasket, head & inlet manifold in reverse of how it was stripped, cleaning up the mating faces one last time with a razor blade as I went.

Once the head was in, new water pump was fitted and it was time to set about timing the engine and fitting the cambelt. Again using a combination of the manual/how to's and common sense (again, wont retreat old ground).

Per the manual you need VAG group timing locking pins - and I'd say if you're attempting this job on your own then you absolutely do as they have a stepped design to lock the pulleys in to the head at the correct place while @ TDC. Typical VAG group... to get you to buy a tool, if they were the same diameter on the pulley and the recess in the head you could just insert a standard punch!!

However with a second pair of hands it can be done with tapered punches, care and patience.

Once correct timing was confirmed by turning the engine over manually, carefully, and ensuring all the relevant marks still line up, it was time to fight with the inlet manifold again - not the easiest of tasks but bizarrely it felt like it was easier going in than removing.

One note I missed previously - when bolting the lower inlet manifold to the head, you must hold vacuum actuator for the swirl flaps in its mid position, away from its resting state, or you risk trapping the delicate flaps between the head and the manifold - and it'll neither seal or move.

basically now it was a case of reinstalling the engine mounts, plugs, coils, ancillaries, covers and refilling with fluids.

Only components of note that was a bit of a pig was refitting the high pressure fuel pump and the EGR pipe. Not the best access and trying to manipulate the fragile pipe while also trying to insert the high pressure fuel fitting into the fuel rail got rather emotional!

Now - going back to a previous fault code;

• P1504 Intake air Fault - Intermittent

I noted the oil filler neck on the rocker cover was rather loose fitting, you need to remove it to be able to remove CYL.1 Coil pack. I think this could be the cause of the fault as its allowing air to pass through the seal.

The metal retainer was bent - after confirmation from Audi that this filler neck is now obsolete, I carefully straightened the retainer with some pliers to create a tighter seal.

After around 8 hours (or a good day) finally - Everything was installed.

I connected the battery, used OBDeleven to clear any faults and on the 3rd attempt of turning over, she fired up, and sounded sweet!

After running up to temp with no issues, I had a new fault along with the steering angle and ABS warning light - which wouldn't clear.

• 00778 Steering Angle Sensor (G85) mechanical malfunction - Static

There was no issue before I took it off the road, so the calibration procedure was attempted where you turn the wheel >30 degrees left, >30 degrees right, drive straight for a short distance, stop with wheel straight & add the acceptance code into the ECU. Then monitor block 060

This took a couple of attempts to get right, but then the fault lights cleared and I had a running FSI with no fault codes!

Now - it may look like I've been busy the last day or two - but in reality the car has been off the road for a number of weeks and ive been doing bits and pieces as and when I've had time/people have been available to help. just documenting all of this now as ive got some spare time!

I'd imagine as the ECU had been powered down for so long it'd lost its calibration setting for the steering angle. if anyone else experiences this I'd highly recommend going through this calibration procedure before replacing components - It worked for me.

Now - Time for a test drive. and WOW! What a difference!

I can honestly say that car is night and day from before I had the timing belt failure and the head reworked.

The car pulls really strongly though the entire rev range, and no hesitation, I can't feel a step change of the car switching between its various modes at 3-4000rpm anymore. Its super smooth. not going to pull up any trees, but its surprised me how well it picks up, quite a nice engine note too.

I do have a slight blow from the exhaust which ill have to sort for the MOT - as It wont be helping emissions/fuel consumption, so ill look to get one made in time, so I can fit and forget, casualty of disturbing it all to remove the manifold etc I guess.

I've travelled a couple of hundred miles now since the rebuild and it hasn't missed a beat. no fault codes, leaks (apart from the exhaust) & no warning lights.

If anyone has any doubt about these engines - Its definitely worth giving one a bit of TLC to get it back its former glory.

 

[Andrew]

@Yellow_Peril re this quote

"One note I missed previously - when bolting the lower inlet manifold to the head, you must hold vacuum actuator for the swirl flaps in its mid position, away from its resting state, or you risk trapping the delicate flaps between the head and the manifold - and it'll neither seal or move."

As you probably noted in the workshop guide there are holes in the actuator brackets and arm specifically there to facilitate pinning the flaps shut on reassembly.

While on flaps did you run the flap adaptation?

Inspiring work, ?'s off to you.

Andy

 

[Yellow_Peril]

@Yellow_Peril re this quote

"One note I missed previously - when bolting the lower inlet manifold to the head, you must hold vacuum actuator for the swirl flaps in its mid position, away from its resting state, or you risk trapping the delicate flaps between the head and the manifold - and it'll neither seal or move."

As you probably noted in the workshop guide there are holes in the actuator brackets and arm specifically there to facilitate pinning the flaps shut on reassembly.

While on flaps did you run the flap adaptation?

Inspiring work, ?'s off to you.

Andy

Thanks, been a fairly long road but happy ive broken the back of it!

No I didn't run the flap adaptation? The car appears to be running normally and I've no logged faults for setpoints/positions not reached etc?

I use OBDeleven rather than VCDS - are you aware of a monitoring channel in the software I can use? guess I could go for a drive and log it and ensure its switching positions?

Edit - Should add while I had the lower manifold out I was extremely careful noting position of the potentiometer and the actuator etc. so I'm confident it went back on in the same position it came out of.

 

[Andrew]

Thanks, been a fairly long road but happy ive broken the back of it!

No I didn't run the flap adaptation? The car appears to be running normally and I've no logged faults for setpoints/positions not reached etc?

I use OBDeleven rather than VCDS - are you aware of a monitoring channel in the software I can use? guess I could go for a drive and log it and ensure its switching positions?

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

fault p1031

If there is a change on that vcds log, when the flaps move, the potentiometer is OK, so N316 would be the suspect. Interestingly, Golf FSI folk say solenoid failure is not uncommon. Mac.

www.a2oc.net

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

fault p1031

If '2.300 V' is the voltage on the valve, it would be constant, as no call for flaps to move. I'll try to do a log while driving. Just need a co-driver/laptop operator! (Like you said though, could all be gibberish!). Mac. Hi Mac, You don't need a co-driver/laptop operator, just put the laptop...

www.a2oc.net

Andy