Symptom library
What's your car doing? Start with the symptom.
Every page here starts from what you can see, hear or smell, then works back to the likely cause, what is safe to drive on, and what a fair repair looks like.
We are not a repair shop. We read your estimate, tell you whether it makes sense, and only introduce you to a vetted local shop if you want one. Advice is always free.
Car won't start
Clicking, slow cranking, or dead silence each point somewhere different. Diagnose it by ear before you pay anyone.
Read itBrake noise and pulsing
Squeal, grind and pulse are three different problems with three different price tags. Here is how to tell them apart.
Read itAC blowing warm
A recharge that lasts a month is not a fix. What actually causes warm air, and what each repair is worth.
Read itCheck engine light
A code is a clue, not a diagnosis. What the light means, and how to keep a scan from turning into a parts cannon.
Read itOverheating
Heat is the one problem that can turn a cheap part into a new engine in about a mile. Here is the order of operations.
Read itShaking at speed
Where and when the shake happens tells a technician more than the shake itself. Learn to describe it precisely.
Read itStrange smells
Your nose is a decent diagnostic tool. Each smell has a short list of causes and a very different urgency.
Read itFluid leaks
Color and position tell you most of it, and one of the puddles on this list is completely normal.
Read itPulling to one side
Pulling all the time, pulling only when braking, and a crooked steering wheel are three separate problems.
Read itBattery light on
The battery light is really a charging system light. You are now running on stored power with a countdown.
Read itTransmission slipping
The most expensive symptom on this list, and the one where the repair-versus-replace math matters most.
Read itSuspension clunks
Some suspension noises are cosmetic. A few of them are the parts that hold your wheel on.
Read itShaking at highway speed
If it only shakes at highway speed, start with the tires and wheels before anyone talks about the driveline.
Read itGrinding while turning
A noise that only shows up when you turn the wheel narrows the list fast. Here is how to tell the cheap causes from the ones that need attention now.
Read itBurning smell after driving
A burning smell that appears right after you park, especially after a long or hilly drive, has a shorter and more specific list of causes than one that happens all the time.
Read itPulls while driving
Before you pay for an alignment, check tire pressure and swap the fronts side to side. It solves this more often than people expect.
Read itAC warm in traffic
Cold on the freeway, warm at a red light, is a specific and fairly narrow pattern. Here is what causes it and what does not.
Read itBattery dies overnight
If the car runs fine all day but is dead again by morning, something is drawing power while it is parked. That is a different diagnosis than a simple dead battery.
Read itRough idle at stops
A car that runs smoothly at speed but shakes or lopes at a stop is telling you something specific about idle quality, not overall engine health.
Read itSlipping on grades
If the transmission behaves normally on flat roads but slips or hunts for gears climbing a grade, heat and load are the story, and it deserves attention before a long trip.
Read itSoft or spongy brake pedal
Pad wear changes the sound your brakes make. It does not change how the pedal feels. A soft, spongy or sinking pedal is a hydraulic problem and it belongs in a different urgency category entirely.
Read itStalls while driving
A car that shuts off while you are driving takes power steering and brake assist with it. This is the one drivability complaint we treat as urgent every time, regardless of how well it runs the rest of the day.
Read itTPMS light keeps returning
A tire pressure light that comes back after you air up is telling you one of three things, and they cost wildly different amounts. Knowing which one you have before you walk into a tire shop is worth real money.
Read itHarsh or delayed shifts
Harsh shifting and a delay before the car moves are early-stage transmission symptoms. Caught here, they are often a fluid service or a solenoid. Ignored, they become the rebuild quote nobody wants.
Read itGas smell
Fuel vapor is the one smell we never tell anyone to monitor for a few days. Some causes are trivial, but the difference between trivial and dangerous is not something you can determine from the driver's seat.
Read itHeater blows cold
A heater that will not warm up sounds like a comfort complaint, and sometimes it is. Other times it is the earliest, cheapest warning that your cooling system is losing coolant — which is the same system that decides whether your engine survives August.
Read itShakes only when braking
A vibration that appears only when you press the brake pedal is telling you something different from a vibration at steady speed. The trigger is the diagnosis.
Read itLoose or wandering steering
If you are making constant small corrections to hold a lane on the I-15, that is not a driving habit — something in the steering or suspension has developed play.
Read itDim or flickering headlights
Headlights are the easiest place to see an electrical problem, which makes them the first thing to change and the last thing that is actually broken.
Read itPower windows or locks dead
Whether one window is dead or all of them are is the entire diagnosis. Those are two different repairs with very different price tags.
Read itSqueal on startup
A belt squeal is one of the few noises that tells you almost exactly what is wrong — if you pay attention to when it happens and what makes it stop.
Read itSmoke from the exhaust
Exhaust smoke is one of the few car symptoms with a built-in diagnostic: the color tells you what is being burned that should not be.
Read itBrowse by system
If you already know roughly where the problem lives, start here.
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