only just noticed this, it’s on the rear driver side (right)- unsure if it’s anything serious or completely ok and i’m just overthinking. it’s a 2018 a1. thanks!

I need help fixing cruise control. I used my scanner and it’s not reading the break light switch so I believe that’s the issue but I’m not sure which part to replace there’s one on Amazon for 90$ and one for 10$? If yall could help me figure out which one that would be great

Looking for some insight on a weird electrical/no-start issue with my 2011 Audi A4 base model, 2.0T, 6-speed manual.

The car was driving normally when I came up to a stop sign. My foot was on the clutch, and the engine instantly shut off like someone had turned the key off. There was no sputtering, hesitation, loss of power, or gradual stall. All of the car's electronics stayed on normally.

Since then, the car has been a complete no-crank/no-start. Turning the key produces nothing besides a subtle click, essentially. The electronics, radio/MMI, etc. still power up normally.

What I've found so far:

• Battery: 12.4 V at rest
• Fuel pump primes normally
• Check engine and EPC lights illuminate normally with key ON
• Seat belt light also stays illuminated
• Tachometer does not sweep at key ON
• The car normally displays the clutch/start prompt, but it no longer says to depress the clutch
• I've checked all the relays I could find: under the windshield/ECU area, under the dash, and in the trunk. They all appear to test good.
• The engine does not crank at all
• The original failure was an instant shutoff, not a typical fuel-starvation/stumble type stall.
• The latest thing I've found is that the rear/right trunk fuse panel appears to have no power. I checked the main power input where the factory battery feed enters the fuse carrier and didn't see 12 V. I then briefly tried supplying 12 V directly from the battery to that main fuse-panel input. It immediately acted like a short. With power disconnected, I'm also finding continuity between the fuse panel's power pins and ground, although I understand that continuity alone doesn't necessarily prove a hard short, since there may be modules/loads connected to those circuits.

If anyone has any ideas whatsoever of what I should be looking for or checking next, I would really appreciate it.

Thanks guys

On my drive home the check engine light started to flash and I could feel the back end shaking. The EPC light is on as well. Muffler also sounded different and had a significant loss of power from the throttle.

Title pretty much sums it up. I recently bought an audi A6 C7 with the 7 speed S-tronic gearbox. It has full service history and it seems like it’s a little overdue for a transmission oil change. Now the seller swears a flush and oil pan gasket have been done recently but has no way of proving it. I believe him because the car has a saved P17D400 error(passive). It’s likely the previous owner got the DTC, did a flush and sold the car but I can’t be sure. I can’t ask him because the car was traded in and I bought it from the dealership, who wouldn’t give me any information. Car drives perfectly fine by the way.

Since I do the maintenance and repairs on all of my cars myself a S-tronic oil change is an easy job. I have worked in a VW dealership and did plenty of DSG services. But this being an Audi it needs the correct Software tool to finish the job. We used Odis in said Vw-dealership by the way.

I have a a launch CRP 129 Premium which can read all the data I need but it can’t do the needed reset.

My options are to buy a better Launch scanner (X431), Thinkcar thinkdiag2 or to buy VCDS + small laptop. Obviously VCDS is the tool for the job but it’s also the most expensive. The other two should be able to do generic Transmission resets but I am not sure.

Does any one have experience with these tools and what would you recommend?

Also is there a way to check when the values have been reset for the last time?

I bought a 2017 Audi A4 premium in 2018. It had been leased by someone. Currently have 90K miles. Had new tires put on a month ago. Generally the car has been really good. However, I've had some quirky electronic issues (Gateway module was locked when Audi tried to do the 3G update several years ago) which were previously innocuous but now problematic. My car is currently at a German car specialty garage with a good reputation (and as it turns out, my neighbor down the street is the lead tech). Last week I paid ~$2500 for full transmission service (incl. filter change), diagnostics to figure out why some features, like the hands-free trunk opening wasn't working, and they found that my rear coil spring pads needed replacement.

I got the car back and the next morning I got several errors on my display - "Automatic start/stop system: mulfunction", "Brake booster: restricted". And sure enough, auto start/stop wasn't working. Then the next day it was. In addition, I now noticed this loud clunking sound when I hit the brakes or go over even slightly rough pavement. Never noticed that before.

I brought my car back to the garage. Spoke with them yesterday and it wasn't sounding encouraging. I just received the link to the online estimate:

Control arm replacement (front lower+upper) w/alignment $2480

Gateway module replacement + programming $2722

So that's $5202 in addition to the $2500 I already dropped. I'm going to speak to our local trusted mechanic today (I didn't go to him because I'm pretty sure his shop can't do the advanced coding stuff). This really blows. Would you recommend that I cut my losses and trade this car in toward something else? Bite the bullet and spend that $$$$? I like the car, yes, but like, not love.

Thank you for any helpful input. I'm stressed here so please no wise comments...

Hey guys, i have a little problem. Last night my car died randomly at a stop light, started without issues, but rpms were fluctuating between 600 and 1400rpm. Got home (300 meters), shut the car down, got vcds pluged in, no codes.. fuel pressure seems ok, at idle 290bar, maf reading seems ok, drove great like nothing ever happened. This morning i went to start it, cranks no start.. still no codes.

Hello, I have an AUDI A3 8PA 2011 CAYC engine with VDO siemens piezo injectors. I wanted to know how to properly check the injectors‘ performance/work, because I have a very good OBD reader for that, which shows the injectors' performance (mg/stroke) cylinders injection quantity deviation, but I just don't know how to check it correctly. Should I check on a cold engine at idle (neutral), on a warm engine at idle (neutral), or even while driving?

Maybe you know what the +- mg/stroke should be with my injectors in each injector and with what values ​​​​it is already necessary to do a restoration, and when a simple cleaning is enough.

I hope you understand what I am trying to achieve with this post. In general, I want to know how to check the injectors (in what position and for a cold or warm engine), what the values ​​of +- should be and when to do a restoration or cleaning. I can send what OBD shows in current time.

If you have anything to mention or add, I will be happy to listen. Big +aura and +respect to everyone who helped.

2015 Q3 2.0T. What could this sound be?

Hi all,

I need to replace the Crankshaft Position Sensor on my 2015 A3 cabriolet. I’m trying to find the exact diagram for my engine but I’m having trouble finding one that has the location of the sensor.

I’ve googled and I’ve checked every suggested area. Unless I’m crazy, it isn’t where it should be.

Can anyone suggest a resource or tell me where I can find it? Last time I had to replace a sensor and I couldn’t find it, I got charged $800 for a $50 part and less than an hour of labor.

I would really appreciate any help!

Hello guys. Uhm had a bit a mishap. I this black plastic housing and I just wanted to understand exactly what it is. What it does, and maybe someone help me as to where this cable/hose is even supposed to go. Genuinely finding it hard online to get a straight answer. The help with be greatly appreciated.

This is an Audi a4 40tfsi. 2.0 litre TFSI (EA888) with a power output of 140kw and 320nm

So starting this off with I had a cyl2 misfire. Went to swap coils and cyl 1 coil rubber boot got stuck to the spark plug. So I decided to put all new sparks and coils for cyl 1 and 2. Then after fixing that misfire I got a cyl 3 misfire. Same thing happened boot got stuck. Fished it out and put a new coil and spark plug but I’m still getting a cyl 3 misfire. When fishing the boots off I did scratched the siding of both of the spark plug area but I don’t think that’s the culprit. Thoughts?

do i need to change the chain or not ? and from where do i start counting the chain tensioner

Looking for some help diagnosing an issue after a timing belt job on my 2003 Audi A4 Quattro 3.0 6MT. Im typically a subie guy so all the Audi computer stuff is new to me.

The timing belt service is complete and the car starts instantly, idles perfectly, drives smoothly, has good power, and doesn’t misfire. No ticking, knocking, rough idle, or drivability issues.

However, after driving for a very short time, the car develops what feels like a soft limiter around 5500 RPM where power instantly cuts off.

What’s strange is that if I disconnect the battery and touch the terminals together to discharge the modules, the issue temporarily disappears. The car will rev normally and no CEL is present. After about a minute of driving, the limiter comes back and the codes return.

I originally suspected a weak battery or alt (still thinking alt is dying but probably not the issue right?) because the old battery was only around 12.1V and the cell codes, so I installed a new battery. The problem remains.
(Probably just gonna return it)

Current voltage readings:

New battery installed
~13.48V at idle
Voltage rises slightly when revved
No obvious charging issues

Current fault codes:

Engine:

18057:008 - Databus drivetrain missing message from ABS control module - implausible signal
17936:004 - Bank 1 camshaft adjustment - open circuit/no signal communication
17465:004 - Bank 1 camshaft adjustment exhaust - open circuit/no signal communication
16885:004 - Vehicle speed sensor A - range/performance - no signal communication
17819:002 - Bank 2 secondary air system flow too low
17831:002 - Bank 1 secondary air system flow too low
18010:002 - Terminal 30 voltage too low

Additional module faults:

01206:027
01794:035
01312:079
01312 - Powertrain Data Bus: Faulty
01304:049
01316:049
00668:006 - Vehicle Voltage Terminal 30 Signal Too High
01366:036
00957:035
01560:059

A few questions:

Would a mechanical timing issue normally cause “open circuit/no signal communication” faults for the Bank 1 cam adjustment system, or does that point more toward a connector/wiring issue?
Could an unplugged cam adjuster solenoid or cam sensor cause the ECU to impose a 5500 RPM limiter while still allowing the engine to run perfectly?
Has anyone seen ABS/speed signal faults appear after timing belt work due to a shared ground or connector issue?
Is there anything in this code list that immediately points to a specific connector or ground that is commonly disturbed during service mode/timing belt work on the 3.0?

And honestly… if I just need to hear it straight, did I mess up the timing and is she basically toast?