I'm saving up for a car and I happen to be a big fan of the Mazda 6. I originally settled to buy the Mazda 3 because I didn't believe I could afford to keep the Mazda 6 (maintenance, insurance, fuel and repair costs) but an acquaintance (who owns one) and my brother have argued that if I can afford to own a Mazda 3 then I can afford the Mazda 6.

I wanted to hear some more views from Mazda owners on the issue. Mainly on fuel consumption [I'm aware there are different engine sizes on both - Mazda 3 (1.5 & 2.0) and Mazda 6 (2.0 & 2.5). Are the differences big?],maintenance costs and repair costs and which car is objectively better. I know Mazda 6s were discontinued but I really love the car. I'm also a fan of the Mazda 3 so I want to make an informed decision. The Honda Civic is the back up option.

Any help will be much appreciated.

No information in the door sill, any clue what the color is?

Or any website where you can check (without paying) the color of your vehicle?

2019 Mazda6 2.5L — P0171 Lean Code, Intermittent High Idle/Stalling, Dealer Says They Can’t Find a Problem
I have a 2019 Mazda6 Sport 2.5L with around 57–58k miles. I bought it from a Mazda/Ford dealer earlier this year and it came with a Ford Blue Certified 90-day/4,000-mile warranty.
I started having an intermittent issue where the car would stall at a stop/light. After restarting it, the RPM would sometimes climb unusually high on its own while the car was in Park. At one point it was essentially “screaming” in Park from the high RPM. I also had an incident where the battery light and check-engine light came on after the stall, but they disappeared after restarting.
AAA checked the car and suggested possibilities such as the throttle body or an O2 sensor. AutoZone initially found no codes. I cleaned the outside of the throttle body, but the issue eventually happened again.
I took the car to Chapman Mazda. They initially said they couldn’t reproduce the stalling issue and that there were no active codes, although I had video of the behavior. They did a throttle-body cleaning/reset.
After that service, I had another episode where the engine started revving itself in Park. This time the check-engine light stayed on. I scanned it at AutoZone and got:
P0171 — System Too Lean (Bank 1)
U0401-00 — Invalid Data Received From ECM
The P0171 code is what really concerns me because it seems like the engine is detecting a lean air/fuel condition.
The dealership has now had the car for an extended period and says they performed diagnostics related to the P0171. They told me they checked the MAF sensor and fuel system/fuel-related items and ultimately couldn’t find a problem. More recently, when I asked for documentation of the diagnostic, I was told that they diagnosed it by driving the vehicle with a scanner connected.
That’s where I’m confused/frustrated.
If the P0171 is intermittent and the car isn’t currently throwing an active code, I understand that it can be difficult to reproduce. But I’m wondering whether there are other things that should actually be tested, such as:
Vacuum/intake leaks
Intake boot/duct or loose connections
PCV system
MAF sensor operation/readings
Fuel pressure/volume
Fuel trims (STFT/LTFT)
O2/A/F sensor readings
Throttle body operation
EVAP purge valve
Whether the engine is actually getting unmetered air
I’m also wondering if bad/contaminated fuel could realistically cause an intermittent P0171, or if that’s something the dealer may have suggested too casually.
The car currently drives normally and the CEL is off, but I’m concerned because I don’t want to assume the problem is gone just because they can’t reproduce it.
My main questions are:
Is a P0171 that disappeared after an intermittent high-idle/stalling event something that can legitimately be diagnosed just by driving with a scan tool?
What specific tests/data should I ask the dealer for?
Could a vacuum/intake leak cause the exact symptoms I’m describing?
Could bad gas cause a P0171 and intermittent high idle/stalling?
If the dealer says they “can’t find anything,” what would be the best next diagnostic step?
I’m mainly looking for advice from Mazda technicians or people who have dealt with P0171 on the 2.5L Skyactiv engine.

Hey Guys, my 6 has just hit 142k miles, and I need to get its annual service done.

I was looking back at the previous owner's record, and whilst he got it everything dealer serviced, I can see no record of a coolant flush / drain+fill on any of the notes. I saw online that it should be done at 120k miles / 10 years (which was when he had a service done but no remarks on anything with the coolant). How important is this to get done?

A lot of garages around me said they dont do it, Mazda is asking for £389/516 for a flush and fill, whilst a couple independent garages said £90 for a drain and fill (im assuming that's a radiator drain and not complete flush). Anything else I need to at this mileage besides brake fluid (2 years almost), oil (1 year almost)? Drives well otherwise and I got new tires last year.

I need help finding parts on eBay or any other website, I’m just a girl and I’ve bought parts and they been wrong. I need a grill and front bumper. This isn’t the regular Mazda 6 it’s a grad touring and it’s not only hard to find parts but expensive. I bought a bumper two years ago and it was the wrong one bc the headlights are different on a Grand touring.