DJ's adventures in A2 land

dj_efk

A2OC Donor
Update - the garage called, they’ve replaced the thermostat but the gauge is still reading 60 degrees - VCDS says the coolant temp according to the ECU is now normal though. Further investigations to be done next week.

very frustrating!!
 

Robin_Cox

Member
What about the coolant temperature according to the dashboard ECU? Within VCDS (or a suitable ODB reader) you can query both channels sent independently by the coolant temperature sender ; one goes to the engine ECU, and the other to the dashboard ECU (and corresponds to the readout given by the needle, but for the whole range, not just 60 degrees and above) - these can both fail independently of each other (I have experienced this in two Tdis). Obviously given that your local independent seem to know what they are doing assume that they actually loaded the engine for 10 miles / 15 minutes to warm it up to 90, because if it was just left idling in current temperatures, it'll never get there.

The above issue is normally heralded by an error code in either engine ECU or dashboard ECU along the lines of 'coolant temperature sensor, something (I've forgotten the exact wording - maybe 'open'?) to earth, sporadic'.
 
In Bath [62.5 miles according to my mate Google] there is a cracking Audi Specialist. VASS on the Brassmills industrial estate. Good enough for Audi themselves to use them for tricky things. Worth a try.

Best of luck, I am much enjoying the Odyssey of Merlin.

PS If waiting for a car to be finished, there are worse places than Bath to be doing it. Brassmills is a short bus ride to the centre.
 

dj_efk

A2OC Donor
I will report back on what the bill is when I’m given it. They said it was just over two hours in labour to replace.

Looks like I’m stuck with the courtesy car for most of the coming week, as like all garages round here, they are flat out busy at the moment; hence can only dedicate an hour here or there each day, which should be all that’s needed to get to the bottom of the problem pretty quickly at least. As mentioned their google reviews and actual rep around around here are excellent so combined with the first impression mentioned above, up to a point I don’t mind what the bill will be as long as it’s calculated in a logical and fair way.

If you pardon the thread swerve for a moment, I had the opportunity to take the courtesy car, a 2014 MY Ford Fiesta diesel, on a good run down into Axminster and back yesterday - hence I found myself comparing it with Merlin. When I first got it in it, it felt cheap and nasty in comparison, being styled inside to appeal to a younger driver in those silver coloured plastics - and with an abundance of buttons up on the middle of the dash for the built-in stereo - that was seen as futuristic at the time but in reality, just feel low-rent. It probably didn’t help that the car is in dire need of an interior valet - what is it with garage courtesy cars round here?? Is it too much to ask to expect a clean interior and mechanicals in rude health?

Anyway, driving it, I had to admit it was pretty competent - both the Diesel engine note and tyre roar were both noticeably quieter than the A2, the suspension was supple yet very taut through the bends, plus the steering wheel seemed to have verbal diarrhoea in terms of how communicative it was, it was almost too sensitive to the road surface I thought, but perhaps that feeling recedes with familiarity. To top off what became begrudging respect fairly quickly, if the instant mpg readout was to be believed then it was insanely economical at A road speeds, despite only having 5 gears. Final verdict: Very good car, would buy one if I needed one or two-person transport and certain aspects I consider important for my cars were not so important, such as carrying capacity (definitely far inferior to the A2), ground clearance (Devon lanes!), build quality (the car felt ok but you get the feeling it would fall apart with normal family use after 10 or 12 years) and general “plushness”.

In conclusion, although I do much prefer my A2, the experience has highlighted where our cars could use some updating - for me as I’ve already addressed engine noise and economy at speed with the PTW six speed gearbox, a good project in this respect would be to do some damping / isolation of tyre noise, as I feel the A2 design is showing it’s age here. Luckily I’m pretty sure there should be some improvements available with some thought / careful use of modern materials.

Has anyone else attempted to address this aspect and found there are some easy first steps that have yielded measurable success? Being a father of 3 young children, I realistically won’t have time for full interior strip-downs however!
 
Last edited:

dj_efk

A2OC Donor
Quick update on where we are:

  • I've 100% confirmed there is no fuel pump located anywhere near the tank - LINK - So the cause of the electrical squealing noise remains a mystery - I will ask the garage where the car is to use a stethoscope while it's in the air to identify and sort the issue out.
  • The latest on the engine coolant temperature saga:
    • They have successfully fixed an issue they found which was the cooling fan was running all the time - this was found to be a faulty sensor.
    • They are continuing to investigate why the gauge is reading 65-ish even when VCDS says the engine is at say 82 degrees - Looks like, incredibly, that BOTH the new genuine VAG thermostat AND the coolant sensor I had replaced were both faulty - that will teach me for asking DS Motorsport to replace components that were working as they should previously! Lesson learned.
Stay tuned!
 

Shoestring7

Member
@gills thread is brilliant and like you, and pointed me towards the whole block heater thing as my commute is fairly short. This is bad, but what's worse is that within 1/4 mile I hit one of the steepest hills in Sussex (up, not down). Always makes me cringe, the thought of a stone cold engine having to pull a car up that hill, however sympathetically I try to treat it. We're lucky to have @Joga 's expertise on hand in this regard :cool:

That's not South Harting is it? I also live at the foot of the downs, so have to climb within 1/2mile of leaving home. Modern turbo engines have such a big mid-range that they can do so without exceeding 3000rpm, not sure about older N/A cars!
 

ukrainian

Member
The latest on the engine coolant temperature saga:
  • They have successfully fixed an issue they found which was the cooling fan was running all the time - this was found to be a faulty sensor.
  • They are continuing to investigate why the gauge is reading 65-ish even when VCDS says the engine is at say 82 degrees - Looks like, incredibly, that BOTH the new genuine VAG thermostat AND the coolant sensor I had replaced were both faulty - that will teach me for asking DS Motorsport to replace components that were working as they should previously! Lesson learned.
The coolant sensor thing reminded me of something similar I had with mine. I wrote it up on here at the time. It appears there are two variants of the 4-wire VAG coolant temp. sensor. One has chunkier terminals but is otherwise the same. I replaced mine with a new one with thicker terminals and it immediately cured the problems and has been good since (a couple of years). The symptoms were that sometimes the engine was difficult to restart from warm-ish. And sometimes the dashboard engine temperature gauge would read garbage (low or no reading, sometimes after initially showing a normal reading). These problems were getting gradually more frequent. I didn't realise at first that the two symptoms could be related, until I found out the temperature sensor has separate channels for ECU and the dashboard. It was easy to rule out the thermostat by measuring the coolant temperature when the dashboad gauge was reading low when it shouldn't. I used my cheap Hilka multimeter for this - it comes with a thermocouple. The coolant was invariably at 80+ degC. I then tried tugging at temp. sensor wires and this would restore normal service after engine restart. So I looked for a replacement 4-wire temp. sensor, there were plenty on eBay with pictures all claiming to be compatible. That's when I noticed that some seemed to have thicker terminals. I ordered one with the thicker terminals and when it arrived I could see the terminals were ineed much chunkier than in the one I was replacing, which by the way had been fitted originally by Audi Watford.

This is just a guess but such a problem could result in ECU reporting both temperature sensor readings incorrectly. Did the garage measure the actual coolant temperature, or did they rely on VCDS read-out alone?
 

ukrainian

Member
When I jumped in for "my go" just now, I fired it up and the orange ABS + one other warning lamp (the orange one with the book circled by an arrow) stayed lit, followed a few seconds after by the bong of death and both a red exclamation mark and what looked like the brake symbol flashing up in the middle of the dash, which was scary! However normal service was resumed by the good old "turn it off / on again". Anything to be worried about?
Check starter motor earth behind n/s head lamp. I'd had similar spurious ABS and sometimes power steering lights for months that would always clear up after engine restart. If allowed to deteriorate this can eventually lead to catastrophic failure - ignition, battery charging and starting problems. Worth investigating as in my case cleaning this up made the car start again and got rid of a bunch of intermittent nuisances like the spurious warning lights, reduced performance, intermittent remote central locking problems etc.
 

Rusty911

A2OC Donor
That's not South Harting is it? I also live at the foot of the downs, so have to climb within 1/2mile of leaving home. Modern turbo engines have such a big mid-range that they can do so without exceeding 3000rpm, not sure about older N/A cars!

No, but funny you should say that as my Mum and her brother grew up in South Harting!

Agree, you don't need too many revs, but labouring a cold engine is probably just as bad. 2-2.5K up the hill feels most sympathetic.
 

dj_efk

A2OC Donor
Just got a call from the garage: Turns out that the impossible is indeed possible, BOTH the new genuine VAG thermostat and temp sender unit that I had DS Motorsport put in have been replaced with new components once again, and now the issue is resolved!!

Furthermore, they pulled up the rear seats to begin the task of isolating the source of the whining noise, only to find that suddenly, nothing they can do triggers the reappearance of it!! Spooky....

They’re going to have one more go first thing in the morning, but if not then it seems Merlin is fixed!

Re: the temperature issue, they have no idea whether incorrect components have been fitted (unlikely, as I got both part numbers from 7zap?), they just replaced with new and all good.

I have a 300 mile round trip coming up in Merlin on Saturday, which will be my first proper run in the car. Let’s hope all goes smoothly!
 

dj_efk

A2OC Donor
Today I well and truly smashed my A2 cherry, with my first proper trip out in Merlin, a 300+ mile round trip up the A303 / A34 / M4 to do a present drop & collection with my parents (I convinced my brother in law to be without Merlin for one more day as my wife needed our Touran to take our children to the Fleet air arm museum, a family favourite day out). I thought I’d share my impressions based on the trip:

The warm-up issue has been fixed, with the faulty thermostat and both temp sensors replaced Merlin takes about 5 miles or so to reach 90 degrees - which corresponds to hitting the main road after 30-40 mph of country lanes in third and fourth. Once up to speed, with cruise control switched on and as the sun came up, I relaxed and started exploring the various DIS functions and setting up the Chorus stereo, road conditions permitting of course.

I’m glad to report that I am well and truly smitten with this little car: With the six speed gearbox it cruises lazily at 70mph in relative peace & quiet and with less road roar than I’d remembered from the initial time I’d been out in it - with the engine note a pleasing distant background hum sounding remarkably like that of a WW2 bomber, albeit heavily muted! However it has a real shove-in-the-back reserve of power for overtaking etc. if you desire, meaning you can press on without working the car hard at all.

Usefully, I found that on the 50mph section of the M4 the car was perfectly happy in sixth at 1500 RPM and 75-80mpg on the instant readout, albeit with a change down when any acceleration was needed or moderate inclines encountered, as otherwise unpleasant vibration enters the cabin. It really does feel like this gearbox, with its short throw and snickety-firm positive change, was fitted as original equipment; it just works with the rest of the car so well and undoubtedly contributes to the grown-up feel.

I found that the car would do 60mpg at 60mph in sixth and on the flat according to the DIS, with low 50s at 70-75. This seemed subjectively to improve a little on the return journey having brimmed the tank with Shell V-Power (including “burping” the tank using the advice I’d read on here). I still think the car should be doing slightly better than this however, I would be interested in opinions on this?

I was also delighted to find my beloved thermos flask of coffee fits perfectly into the rear cup holder, although it took a good few tries in the dark before I found the knack of placing it in there first time. In addition my wallet fits perfectly into the little cubby hole by the stereo, the boot swallowed the insane amount of Christmas presents that comes with the territory with large families - and the heated seat on the “1” setting all the time are a godsend, otherwise the leather would have been somewhat chilly on my backside! I was further delighted to discover that the issue with the rear interior light flickering appears to have fixed itself - spooky!

The whining noise is still present although somewhat muted now after I filled the tank, which is strange all round as the garage that had it have confirmed its coming from the fuel filter - they recommend changing the filter element as a first action. Could it be that yet another brand new component I had installed at DS Motorsport is also faulty in some way?!

Questions:
1) Both of my headrests are firmly stuck in the seats and no amount of pulling or levering up with the button pressed will make them budge! Any ideas?

2) In addition, I think the driver’s side front door speaker is weaker than the others as it required use of the fader to right hand side to compensate for its lack of volume compared with the rest, is this a common issue?

Next update will contain lots of pictures I promise!
 
Last edited:

gills

A2OC Donor
I found that the car would do 60mpg at 60mph in sixth and on the flat according to the DIS, with low 50s at 70-75. This seemed subjectively to improve a little on the return journey having brimmed the tank with Shell V-Power (including “burping” the tank using the advice I’d read on here). I still think the car should be doing slightly better than this however, I would be interested in opinions on this?

I would have thought you should get at least 60mpg, if not 65, on a steady 70mph motorway run (assuming no headwind or water on the roads). The best way to check it is calculating consumption at the pump, with the tank brim to brim, rather than the DIS. I have found the DIS reasonably accurate for average consumption, although it was a bit optimistic in the summer. I would see how you get on over a few tanks, but check the obvious - tyre pressures, brakes dragging etc
 

dj_efk

A2OC Donor
Yes that was what I was expecting.

As I'm loaning the car out it's difficult to check the actual tank-to-tank at pump calculation - as I say the tank average seemed to be a bit higher compared to what the instant was reading most of the time during the day, so hopefully you're right and there isn't an issue.

Tyres are at full load pressures as per the fuel flap, brakes have just been checked / serviced etc., wheel alignment is correct - So whatever it could be (if there is an "it"), may not be so obvious.
 

dj_efk

A2OC Donor
Wishing everyone reading this a happy rest-of-Christmas and a much, much better new year.

I finished the year having achieved what I’d set out to despite current events, but my god I am grateful we now have both a vaccine and a deal with Europe, both good reasons to be hopeful about our collective futures.

Have a pic of Merlin taken just now at Charmouth beach. Thanks for reading!

1609072138420.jpeg
 

timmus

A2OC Donor
Usefully, I found that on the 50mph section of the M4 the car was perfectly happy in sixth at 1500 RPM
My own A2 will also do this, but I never allow it to. Even if the VGT turbo in the TDI90 allows enough torque to be developed and the engine seems comfortable, low-rev, high-load scenarios are terrible for the engine and gearbox bearings, and are thought to be a major contributor to oil-pump-mechanism wear. As such, the moment that I go below 60mph, I change down to 5th, even if that increases fuel consumption slightly. Long term, I believe this to be the lesser evil.

Cheers,

Tom
 
Top