Azure Blue - A2 FSI Faults and Fixes

A

AndyBa

Member
I thought I'd start a Project thread to document progress maintaining and repairing my Azure blue FSI.

So when I bought the car in 2023 it
didn't start on first attempt and needed a bit of throttle, it had a minor misfire, badly resprayed rear arches and signs that the passenger doors had been partially resprayed. Oh and 4 ditch-finder tyres. This doesn't sound promising but in reality the overall condition was very good for its age. Complete with the book pack showing patchy service history...I think it started on long-life service intervals which haven't turned-out to be cost effective based upon various forum posts!

I've tried to resolve the poor starting and misfire on cylinder 2, but neither a new coil pack, nor swapping a known good spark plug or adding another earth strap has resolved this issue. Thanks to lots of help/advice from @PlasticMac and other members. I wonder if there is a breakdown in the wiring is the issue (I had this on my Beetle TDI). I did have the A2 booked in at WOM Automotive, however I had to cancel since my colleague was on paternity for a month, so I need to reschedule.

Today I was investigating why the red genie oil light has recently been coming on. I ordered a pressure gauge kit since I couldn't find mine....I've now uncovered 3 sets! This is an issue I had on the ex BG 1.6 Caddy and I was hoping the outcome wasn't the same.
So fully warmed-up at idle the oil pressure is 1 bar, upping the revs to 4000 shows up to 4 bar (the gauge is marked-up 0.6-0.8) so I'm not sure why it was alerting.
I had a spare oil pressure switch so have swapped it out and will monitor.

I also started to change the rear arches for a pair I bought off @Ami . Have swapped the OS one, but the NS one had a stuck screw. I've got it turning but I suspect the captive nut has sheared. I'd have drilled it out but my son has borrowed my electric drill :(

I also decided to check the rear brakes since the pads are binding and "clonk-off" when starting off. The discs and pads have been renewed but when I took the caliper off the pads were locked in the carrier. I needed to use quite a lot of force to persuade them out with a strong screwdriver (that's not right). I cleaned the sliding surfaces and re-installed with the rattle shims but they were far too tight, so I removed the lower shim and the pads are snug and release when taking the handbrake off. I need to get some new quality pads (not sure what brand are currently installed.

I also removed the bonnet rubber drains, the left one was full of debris. I also sprayed 3-in-1 on the gearbox selector pivots.

I will get some service bits and change the oil, oil filter, air filter and cabin filter. I already have the spark plugs. The dipstick readings are questionable since I'm sure any oil in the tube distorts the readings. I'm going to try a netting rail (plastic covered spring thingy).

'til next "playtime" :{) .
 
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Belated Update:
I've got other distractions going on in my life!

So I've replaced the two rear arches so the car looks loads better, thanks @Ami . I'm going to remove the Ali rings on the wheel caps and that should improve the looks further.

I've done an oil change. The oil filter was a PITA to get off. I had to improvise with my tools to fit the "top nut". Why don't they all have a standard shape?!

edit....I also replaced the oil pressure guage with the one I had from the Caddy. No more red genie lamp since. I wasn't expecting that since I thought the sensor would either work or not.

I've replaced the spark plugs but there is still an issue with starting and cylinder 2 misfire recording on the VCDS logs but not the initial error code listing. I need to take some fresh VCDS logs.
 
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Last week I overdosed the A2 on some Redex and took it for an Italian tune-up to work and back, it's a 32 mile route mainly on dual carriage way / Motorway.

Today was MOT test time which it passed with only an advisory for the number plate suffering minor delamination.... YAY!
When I started it this AM it started first time ! however when I repeated it would only start on second attempt.
Tonight I connected up VCDS. Firstly I looked for fault codes:

Intake Air System: Leak Detected
P1504 - 35 - 10 --- Intermittant
edit: just read @Yellow_Peril post:
"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."

I'll take another look at the retainer prongs

I also took some readings whilst taking it for a fast drive on a local dual carriageway. There are still some low-level misfire (single figures) so a lot lower than before.

Not sure how I upload full files, but here is a summary of the log
 

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On the face of it, the crankshaft sensor, G28, is dropping out intermittently. I think that would feel like a misfire, but not trigger a DTC, as the ECU doesn't know the engine is running.
So far, Group 141 is a mystery, even Ross-Tech can't help, so I'd ignore that.
Fuel pressure looks good.
Mac.
 
Changing the G28 looks to be a breeze....not 😞

Engine speed sensor/Crank position sensor FSI

For a change this is a fix rather than a problem and I hope it helps a few people with some erratic running problems. I was getting a intermitent warning on the sensor in the last few weeks and the car refused to start twice but now that is has been fixed it has cured a myriad of problems...
www.a2oc.net www.a2oc.net
 
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