Hey everyone! I'm hoping to get some advice about issues I'm experiencing with my 2019 Audi A6. Over the past month or so, I've noticed some performance problems that are getting progressively worse, and I think it might be related to the fuel injectors.

The symptoms I'm dealing with are a rough idle when the engine is warm, especially at traffic lights, decreased fuel economy by about 15 to 20 percent compared to what I was getting before, occasional hesitation or stumbling during acceleration, particularly when accelerating from a stop, and a check engine light that comes on intermittently.

I took it to a quick lube place for an oil change, and the technician mentioned that the engine seemed to be running rough. He suggested it might be carbon buildup or dirty fuel injectors and recommended an injector cleaning service they offer. However, I'm skeptical about whether their cleaning service would actually solve the problem or if this is something more serious.

I did some research online and learned that direct injection engines like the one in my A6 are prone to carbon buildup on both the intake valves and the injectors themselves. Some sources say that cleaning can help if caught early, while others suggest that severely clogged or failing injectors need to be replaced entirely.

I'm trying to figure out whether I need car fuel injector cleaning and replacement services, or if this is something else entirely. I don't want to spend money on cleaning if the injectors are actually failing and need replacement. But I also don't want to replace injectors unnecessarily if cleaning would solve the problem.

The check engine codes I pulled using my OBD scanner show multiple misfire codes on different cylinders, which from what I've read could indicate injector problems, ignition coil issues, or even spark plug problems. The codes appear and disappear, which makes diagnosis more complicated.

One thing I'm confused about is the difference between various cleaning methods. I've heard about fuel system cleaners you add to the tank, professional cleaning services that run chemicals through the fuel system, ultrasonic injector cleaning where they remove and clean the injectors externally, and walnut blasting for direct injection carbon buildup.

My main questions are how do I know if my injectors need cleaning versus replacement, what's the most effective cleaning method for direct injection engines, is this something I should have done at the dealership or can independent shops do it properly, and how much should I expect to pay for either cleaning or replacement?

I'm also wondering if there are preventive measures I should be taking. Should I be using premium fuel instead of regular? Are fuel system cleaner additives actually effective? How often should injector cleaning be done as preventive maintenance on direct injection engines?

The Audi dealership quoted me a high price for diagnostics and said they'd need to test the injectors individually to determine if cleaning or replacement is needed. They mentioned that Audi injectors are expensive, and if multiple injectors need replacement, it could cost several thousand dirhams.

I've heard mixed opinions about aftermarket injectors versus OEM. Some people say aftermarket injectors from reputable brands work fine and save a lot of money. Others insist that you should only use genuine Audi injectors to ensure proper performance and longevity.

Another consideration is whether all injectors should be replaced at once if one fails, or if it's okay to replace just the faulty ones. Some mechanics say if one injector fails, the others are likely not far behind, so it makes sense to do them all together. Others say that's unnecessary and just replace what's actually bad.

I'm also curious about whether this problem could be related to fuel quality. I usually fill up at reputable stations, but could bad fuel cause these symptoms? Should I try running a couple tanks of premium fuel with injector cleaner additive before pursuing professional service?

Has anyone dealt with similar symptoms on an Audi or other direct injection vehicle? What ended up being the actual problem, and what solution worked for you? Any recommendations for shops in Abu Dhabi that specialize in fuel system diagnostics and injector services?

I really want to get this sorted out properly because the rough running and poor fuel economy are frustrating, and I'm worried that continuing to drive with misfires could cause damage to the catalytic converters or other components.

Thanks in advance for any guidance!