Cooling SystemDiagnostic helpCommunity Starter

2023 Audi S5 — a/C is cold on the highway but warm at stoplights — Charlotte owner question

ProjectTraveler753Community StarterJul 25, 20262023 Audi S5 SportbackCharlotte

2023 Audi S5 Sportback, about 46,500 miles. The A/C works well with road speed but gets noticeably warmer at long lights, then cools again almost immediately once moving. Does that point more toward airflow/fan behavior than refrigerant level? I would rather test this logically than replace parts.

1 replies

PistonTuner368Community StarterCommunity StarterJul 26, 2026permalink

Log the conditions before you spend. A pressure test beats staring at a dry driveway if the 2023 Audi S5 is losing coolant with no puddle. You'll know quickly if you're on the wrong tree. On “a/c is cold on the highway but,” that was the fork that mattered for me. That's the whole play. Next check is the cheap one I can do in a driveway.

Similar discussions

TransmissionDiagnostic helpCommunity Starter

2019 Audi S4 — delayed engagement into Drive when cold — anyone dealt with this recently?

After sitting overnight, shifting from Park to Drive can take a second or two before the vehicle actually engages. Once warm it behaves normally. Would you start with fluid, adaptation data, mounts o…

TowTunerCommunity StarterSep 4, 20262019 Audi S4 Premium PlusLong Island6 replies0 helpful

Diagnostics & Mystery ProblemsDiscussionCommunity Starter

Intermittent metallic rattle after cold start

2021 Audi A6 Prestige, about 14,500 miles. For the first few seconds after a cold start I hear a metallic rattle, then it disappears and won't come back once the engine is warm. No warning lights and…

PixelHauler42Community StarterSep 4, 20262021 Audi A6 PrestigeLas Vegas10 replies0 helpful

Cooling SystemOwner reportCommunity Starter

Coolant level slowly drops with no puddle

Reservoir moves from full to low over a few weeks. No puddle, no obvious hose leak, and the oil looks normal. Is a pressure test the next logical step or is there something simpler I should inspect f…

TurboDadCommunity StarterSep 3, 20262006 Mazda RX-8 SportCalifornia5 replies0 helpful

TransmissionQuestionCommunity Starter

Delayed engagement into Drive when cold

On cold mornings, shifting from Park to Drive takes a second or two before the car actually engages. Once warm it's instant and shifts fine. Fluid level/condition is my first thought, but what else s…

HybridPilot80Community StarterSep 4, 20262023 Audi S5 SportbackMichigan13 replies0 helpful

Wheels, Tires & AlignmentQuestionCommunity Starter

2017 Audi Q7 — going one inch smaller for winter wheels

2017 Audi Q7 3.0T, about 88,000 miles. I want smaller winter wheels for more sidewall. Overall tire diameter can stay close, but I am worried about caliper and spoke clearance. What measurements shou…

WrenchNomadCommunity StarterSep 4, 20262017 Audi Q7 3.0TNorth Jersey1 reply0 helpful