EZ Swap LLC services the Audi A4/S4 in Phoenix, AZ, covering model years 2005, 2007. If your A4/S4 has a warning light, a strange noise or a safety recall question, our mechanics can diagnose it and give you a clear quote first.
To help A4/S4 owners know what to watch for, we reviewed public records from the National Highway Traffic Safety Administration (NHTSA). For these model years NHTSA has 494 owner complaints on file for the A4/S4 and 0 safety recall campaigns. The most-reported problem areas are air bags (208), exterior lighting (142), electrical system (41).
Most-Reported Audi A4/S4 Problems
These problem areas come up most often in NHTSA owner complaints for the A4/S4 (all model years combined). Complaint counts reflect reports filed, not the share of vehicles affected, so popular and older models naturally have more.
| Problem area (NHTSA component) | Complaints | Share | |
|---|---|---|---|
| Air Bags | 208 | 42% | |
| Exterior Lighting | 142 | 28% | |
| Electrical System | 41 | 8% | |
| Power Train | 30 | 6% | |
| Engine | 30 | 6% | |
| Engine And Engine Cooling | 23 | 4% | |
| Vehicle Speed Control | 18 | 3% | |
| Fuel System, Gasoline | 16 | 3% |
Air Bags
208 of the 494 complaints (42%) mention airbags and seat belts. Airbag and restraint issues are often tied to open safety recalls, which are repaired by the manufacturer at no cost to you. Check your VIN on NHTSA's recall lookup first, and we can help with related warning lights and diagnostics. See our auto repair page.
Exterior Lighting
142 of the 494 complaints (28%) mention lighting and visibility. Lights, wipers and visibility items are quick to fix and are on every rideshare inspection checklist. We check them as part of our inspection prep. See our rideshare inspection prep page.
Electrical System
41 of the 494 complaints (8%) mention the electrical system. Electrical problems are made worse by desert heat, which ages batteries, cables and connectors. We test the battery, starter and charging system and trace faults to the actual part. See our battery replacement and starter & alternator repair pages.
Audi A4/S4 Complaints by Model Year
The A4/S4 model years with the most NHTSA complaints on file are 2005, 2007. Older model years have had more time to collect reports, so use this table as a guide for what to inspect, not as a verdict on any one vehicle.
| Model year | Complaints on file | |
|---|---|---|
| 2005 | 262 | |
| 2007 | 232 |
Audi A4/S4 Check Engine Codes
NHTSA owner complaints rarely cite specific trouble codes for the A4/S4, so we do not have a model-specific ranking to show. These are the check engine codes we see most often on vehicles in Phoenix heat, and any of them can show up on a Audi.
| Code | What it means |
|---|---|
| P0420 | Catalyst efficiency below threshold (bank 1) Often a worn catalytic converter, but failing oxygen sensors or exhaust leaks can set it too. Can cause an emissions test failure. |
| P0300 | Random or multiple cylinder misfire Worn spark plugs, failing ignition coils, fuel or vacuum problems. Do not ignore a flashing check engine light. |
| P0171 | System too lean (bank 1) Often a vacuum leak, dirty MAF sensor, weak fuel delivery or a failing oxygen sensor. |
| P0455 | EVAP system large leak Missing or loose gas cap, or a disconnected or cracked vapor hose. |
| P0128 | Coolant temperature below thermostat regulating temperature Usually a thermostat stuck open. Fix it to restore efficiency and cabin heat. |
| P0442 | EVAP system small leak Loose or worn gas cap, cracked hose or purge or vent valve. |
| P0301 | Cylinder 1 misfire Commonly a bad spark plug or ignition coil on that cylinder. |
| P0401 | EGR flow insufficient Clogged EGR passages or a stuck EGR valve. |
Got a check engine light on your A4/S4? A code is a clue, not a diagnosis, so we scan it and test the system before replacing anything. See our check engine light diagnostics.
Serious Incident Reports
Of the NHTSA complaints on file for the A4/S4, 14 involved a crash, 4 involved a fire, 15 reported injuries. These numbers are drawn from self-reported complaints and are not verified findings. If your vehicle has an open recall, get it repaired promptly.
Keeping a Audi A4/S4 Reliable in Phoenix
Arizona heat is the hardest test a Audi will face. Batteries, belts, hoses, tires and engine oil all wear faster here, and a A4/S4 that spends its life in stop-and-go Valley traffic needs maintenance earlier than the owner's manual's normal schedule suggests.
Our recommendation for A4/S4 owners: follow the severe-service schedule, test the battery before every summer, inspect brakes and tires twice a year, and have any warning light diagnosed instead of ignored. If you are shopping for a used Audi A4/S4, a pre-purchase inspection shows what the paperwork does not.
Audi A4/S4 Services at EZ Swap LLC
Get the details on our Phoenix Audi A4/S4 repair service, or choose a service below.
Auto Repair
All makes and models, from domestic trucks to imports.
Details →Rideshare Inspection Prep
Get approved for Uber, Lyft and more.
Details →Battery Replacement
Test, replace and protect against Phoenix heat.
Details →Starter & Alternator Repair
Charging and starting system repair.
Details →Oil Change & Maintenance
Oil, filters, fluids, tires and scheduled service.
Details →Car A/C Repair
Phoenix heat demands cold air.
Details →Audi A4/S4 FAQ
What are the most common problems with the Audi A4/S4?
Based on NHTSA owner complaints, the most-reported problem areas for the Audi A4/S4 are air bags (208), exterior lighting (142), electrical system (41). Complaint counts reflect reports filed, not the share of vehicles affected.
Which A4/S4 model years have the most complaints?
The A4/S4 model years with the most NHTSA complaints on file are 2005, 2007. Older years have had longer to collect reports, so inspect any specific vehicle before buying.
What check engine codes are common on the Audi A4/S4?
NHTSA complaints rarely cite specific codes for the Audi A4/S4. On Phoenix vehicles in general, we see P0420, P0300 misfires, P0171 lean conditions and EVAP leaks such as P0455 and P0442 most often. Bring yours in and we will scan and test it.
Does the Audi A4/S4 have any safety recalls?
NHTSA lists 0 recall campaigns for the Audi A4/S4 across model years 2005, 2007. Each recall applies only to certain vehicles, so enter your VIN at nhtsa.gov/recalls to see if yours is affected.
Do you repair the Audi A4/S4 in Phoenix?
Yes. EZ Swap LLC repairs and maintains Audi vehicles including the A4/S4, at 9050 N 9th St in Phoenix. Call or text (602) 246-9063 for an appointment.
Is a pre-purchase inspection worth it for a used Audi A4/S4?
Yes. An inspection checks the engine, transmission, brakes, suspension, A/C and electrical system, and scans for stored codes, so you know the real condition before you buy.
How often should I service my Audi A4/S4 in Phoenix?
Follow the severe-service schedule in your owner's manual, since heat and stop-and-go driving count as severe use. Test the battery before summer and inspect brakes and tires regularly.
More Audi Models We Service
Source: public complaint and recall records from the National Highway Traffic Safety Administration (nhtsa.gov). Counts reflect reports filed and do not predict the condition of any individual vehicle.