New Members - please read before posting

Welcome to the Audi Owners' Club - An Independent community!

Membership is completely free, and our community is built by enthusiasts, for enthusiasts. We’re a proudly independent, non-official club, so all the help and opinions you’ll find here come directly from members with real experience of Audi ownership.

Join the club now!

Help please, what is this residue on the engine?

Followers

May 31, 20233 yr

I am about to purchase a Audi A4 Automatic 2015 plate. I'm happy with what I have seen so far but I took the hood off the engine and would like some advice as to what the yellow marking could be, looks like something has been leaking? Is it nothing to worry about considering the car is 8 years old?

Much appreciated!!

Edited May 31, 20233 yr by audiCM73

May 31, 20233 yr

8 hours ago, audiCM73 said:

I am about to purchase a Audi A4 Automatic 2015 plate. I'm happy with what I have seen so far but I took the hood off the engine and would like some advice as to what the yellow marking could be, looks like something has been leaking? Is it nothing to worry about considering the car is 8 years old?

Much appreciated!!

Hi if its not wet or slimy don't worry its just moisture driven corrosion, brush it off with a brass brush and see if it reappears.

Steve.

Create an account or sign in to comment

Followers

Go to topic listing

Announcements

A% front suspension groan
Audi A5 Club

A% front suspension groan

IainH · Thursday at 04:30 PM2 days

Last summer while in the heat of southern France, my A5 (Dec-2017, 40,000 mile) developed a front suspension creak. It was always at low speed and particularly when turning left. The car was completely checked on my return, 'shaked, rattled and rolled', but steadfastly refused to creak once, however, everything was checked, levered, put in a shaking plate, and no creaks or movement in joints found, and so while noisy, the car was declared 'good' (safe). The sound is very like the creak heard her
- 3 replies
- 97 views
IainH

Thursday at 04:30 PM2 days

cliffcoggin

9 hours ago9 hr
Head gasket?
Audi A6 (C6) Forum

Head gasket?

Duane1611 · 17 hours ago17 hr

My coolant expansion bottle keeps emptying after about 6/7 miles, I suspected a leaky bottle cos I'd had that problem before but I changed it and it's still happening. Now I'm looking at the oil and it's not good, can someone confirm head gasket failure? Or another explanation for what's happening? Cheers Duane
- 8 replies
- 99 views
Duane1611

17 hours ago17 hr

Duane1611

10 hours ago10 hr
Free Allroad 17” Twin Spoke Alloys (A6 C5)
Audi A6 (C5) Forum

Free Allroad 17” Twin Spoke Alloys (A6 C5)

56Doc · February 25Feb 25

I’ve had these wheels since I sold my old 2004 Allroad many years ago & now they’re just in the way, so if anyone wants them, they’re available in Weston-super-Mare! they were refurbished after I bought them, I used them as my summer wheels. I know 1 wheel had a chip in the lacquer, but that was it, they’ve been undercover in the garage ever since I Sold the car, So should be pretty much the same. free to collector if no takers I’ll have to scrap them.
- 33 replies
- 1,658 views
56Doc

February 25Feb 25

56Doc

11 hours ago11 hr
Mod list and a few pics from last road trip to Europe.
Audi A3 (8V) Forum

Mod list and a few pics from last road trip to Europe.

T80HNO · March 2Mar 2

Mods so far :- DBA 4000 series T3 Discs to front and rear Ferodo DS2500 pads to front Pagid street plus pads to rear Motul RBF 660 brake fluid RS3 Brake cooling ducts HEL stainless braided hoses Road wheels Standard running 225 40 18 Pirelli P zero pz5 tyres Track wheels Rotiform KPS 18 x 8.5 running 245 40 18 Michelin pilot sport cup 2 connect tyres Retrofitted TPMS system as per the RS3 for live morning of the tyre pressures and temp
- 10 replies
- 992 views
T80HNO

March 2Mar 2

T80HNO

12 hours ago12 hr
Car is a pile of junk, gone to go out and showing 24 faults.
Audi Q6 Club

Car is a pile of junk, gone to go out and showing 24 faults.

Audi Q6-Etron · May 25May 25

Hi all, well the Audi Q6 car has gone well and truly mad, claims to have 24 faults, just got in the car to go out and now can not, Audi can not send a tech support person till tomorrow. Here are just some errors the car is showing, here are the top 16 faults Steering Fault. Please stop vehicle Rear Cross-Traffic unavailable Rear Turn Assist unavailable Side Assist unavailable Lane Departure Warning currently unavailable Exit Warning unavailable Emergency Assist currently unavailable Adaptive L
- 28 replies
- 786 views
Audi Q6-Etron

May 25May 25

Audi Q6-Etron

13 hours ago13 hr
Alternator failure related to mild hybrid system?
Audi A7 Club

Alternator failure related to mild hybrid system?

PocketsAintEmptyCuh · October 16, 20232 yr

I've been seeing more and more posts across FB and multiple forums about people having the alternator failure related to the 48v mild hybrid system and wanted to see if anyone has had this issue and how their experience has been. I know in USA they have announced a TSB with an extended warranty for 7 years but I am trying to get more info from Audi UK but not getting anywhere. Has anyone had this issue and if so has Audi fixed it (if out of warranty)? It seems to be tha
- 667 replies
- 214,059 views
PocketsAintEmptyCuh

October 16, 20232 yr

DieSel-Q

17 hours ago17 hr
Battery replacement
Audi A3 (8L) Forum

Battery replacement

LucyB · 20 hours ago20 hr

Hello All - My battery has died and I'm all set to replace it myself. We jumpstarted the car last week and despite it initially sending me a lot of mad messages about nothing working, once I got it going and drove a mile, it was all fine. 2 days later, battery flat again. Mu question is, if I disconnect the old battery and replace it, will all my computer settings be lost?
- 4 replies
- 55 views
LucyB

20 hours ago20 hr

LucyB

17 hours ago17 hr
Mini Road Trip.
Road Trips

Mini Road Trip.

Anton8 · July 10, 2025Jul 10

Hi. Just arranged a mini road trip to the West Country. Day 1. Travel To St Austell to stay overnight in 16th century pub. Stopping at Exeter Services for a recharge. Day 2. Travel to The Eden Project, then on to The Lost Gardens of Heligan and Mevagissey. Back to the pub overnight. Day3. Travel to The Cheddar Gorge, stopping at Exeter Services for recharge. Then home. Possibly stopping at Fleet or Cobham Services for a quick charge. Might not sound much but it just takes a bit more organising t
- 12 replies
- 2,297 views
Anton8

July 10, 2025Jul 10

Magnet

19 hours ago19 hr
S3 Parking Sensors
Audi A3 (8Y) Forum

S3 Parking Sensors

DamianS3 · Friday at 08:22 PM1 day

Hi. I drive an S3 2021 Hatch Sportback. My car came from new with Rear parking sensors that Beep - But no Front Parking Sensors. I have been looking around for someone to fit Front parking sensors and a Rear Reversing Camera to my S3. One company called AIC (Advanced in car Technologies) which are based in Poole around Dorset looks good, however they are over 500 Miles from where I live. AIC say they use Genuine Audi Parts and can fit them to my car (8Y 2021) and can fit them and set my car up a
- 3 replies
- 125 views
DamianS3

Friday at 08:22 PM1 day

joe6

20 hours ago20 hr
Door hinge replacement
Audi A3 (8P) Forum

Door hinge replacement

vr6bro · yesterday at 12:39 AM1 day

Hey guys im from new zealand, i got a a3 8p with a vr6, it has 45xxxkms. it has front right damgage and the door was hit in the crash, Im trying to replace the front right upper door hinge but its impossible to access the inside bolt to remove it from the body. Ive searched everywhere on google and youtube and audi forrums and have seen no one try this repair or any advice. Has anyone on here attempted something like this or seen someone do it??
- 2 replies
- 93 views
vr6bro

Yesterday at 12:39 AM1 day

cliffcoggin

20 hours ago20 hr
Coding drl
Audi A5 Club

Coding drl

Josh gall · yesterday at 02:47 AM1 day

Hi all I have a Audi a5 3.0tdi 2015 I’m trying to code my drl to turn on when I unlock the car I was told they run of light sensor in the windscreen im wanting them to come on no matter time of day I’m using obd11 to try this but isn’t seem to be getting anywhere I’ve tried all sorts of stuff I keep getting function unavailable does this need to go to a coder Thanks in advance
- 2 replies
- 62 views
Josh gall

Yesterday at 02:47 AM1 day

Josh gall

21 hours ago21 hr
Yippee I got one….
Audi A2 Club

Yippee I got one….

Hulltr6man · Friday at 04:08 PM1 day

Well I’ve been and gone and done it…. I’ve just taken delivery of a mint A2 1.4Tdi with 76,000 miles on in Ebony Black. She is beautiful with beige leather and all the toys inc a working pan-roof!! My question is - Do I get her chipped for an extra 25 bhp or leave her as standard 🤔🤔🤔
- 6 replies
- 136 views
Hulltr6man

Friday at 04:08 PM1 day

StanH

22 hours ago22 hr
Does anyone know what this high pitched noise is?
Audi A1 Club

Does anyone know what this high pitched noise is?

redaudi20 · December 11, 2025Dec 11

IMG_2335.MOV Hi there, My A1 1.6 TDI Sport 2017 makes this high pitched noise which sounds like it’s coming from the right rear side. It more tends to happen when the weather is cold. It starts when the car has been going for a couple miles and stops as soon as you turn the engine off. I have attached a video of the noise. Does anyone know what this could be? Thanks IMG_2335.MOV
- 4 replies
- 757 views
redaudi20

December 11, 2025Dec 11

StanH

22 hours ago22 hr
A6 C5 all road abs problem
Audi Technical

A6 C5 all road abs problem

jcstuckinmuck · 22 hours ago22 hr

Wondering if anyone could help, my all road A6 C5 , when I drive it and rex past 2000rpm the abs light comes on with the esp and suspension level control light, if I turn car off and restart the light go out, if I keep under 2000 rpm no lifts come on, I have logged with vcds, and only fault is brake pressure implausible, when I do live reading it fluctuates between 0 to 33, when I put foot on brake the pressure goes up as it should, I have changed the abs unit and brake light switch. Is there a
- 0 replies
- 33 views
jcstuckinmuck

22 hours ago22 hr

jcstuckinmuck

22 hours ago22 hr
1994 Audi 100 Quattro 2.8E engine cuts out in high heat
Classic Audi Club

1994 Audi 100 Quattro 2.8E engine cuts out in high heat

TomMelluish · May 30May 30

Hi everyone, I have a 1994 2.8E Audi 100 Quattro saloon with ~130k miles on the clock. It's developed a problem with the engine cutting out if driven above ~65mph on days warmer than 27 Celsius. Neither the garage or main dealer have been able to find any fault. One mechanic speculated that the fuel pump might be at fault, but the problem has persisted after replacing it. Has anyone experienced this with a similar model? Thanks! Tom
- 2 replies
- 109 views
TomMelluish

May 30May 30

TomMelluish

22 hours ago22 hr

Welcome to the Audi Owners' Club - An Independent community!

Help please, what is this residue on the engine?

Featured Replies

Create an account or sign in to comment

Topics

A% front suspension groan

Head gasket?

Free Allroad 17” Twin Spoke Alloys (A6 C5)

Mod list and a few pics from last road trip to Europe.

Car is a pile of junk, gone to go out and showing 24 faults.

Alternator failure related to mild hybrid system?

Battery replacement

Mini Road Trip.

S3 Parking Sensors

Door hinge replacement

Coding drl

Yippee I got one….

Does anyone know what this high pitched noise is?

A6 C5 all road abs problem

1994 Audi 100 Quattro 2.8E engine cuts out in high heat

Account

Navigation

Search

Configure browser push notifications

Chrome (Android)

Chrome (Desktop)

Safari (iOS 16.4+)

Safari (macOS)

Edge (Android)

Edge (Desktop)

Firefox (Android)

Firefox (Desktop)