Fuel economy
How to calculate MPG by hand
The full-tank method, the partial fill-up trap that ruins most homemade logs, why your dashboard reads optimistic, and a calculator that runs in your browser.
Diagnosis · 10 minYour gas mileage dropped
Cheapest checks first: tire pressure and season before oxygen sensors and dragging calipers — and how to tell a real drop from tank-to-tank noise.
Method · 9 minHighway vs city MPG
Kinetic braking losses, idling fuel burn, overdrive gearing, and why hybrid vehicles flip the rule completely.
Fuel · 9 minOBD2 fuel economy accuracy
What OBD-II dongles actually read, why their MPG inherits estimation errors, and when scanner sensor logs are genuinely useful.
Fuel · 9 minPremium vs regular gas
Required vs recommended in the manual, what knock sensors do, and how to settle the question with a 6-tank fuel log test.
Conversion · 7 minL/100km to MPG conversion
The exact 235.215 conversion formula, the critical US vs Imperial gallon trap, and rapid mental math shortcuts.
Maintenance
Maintenance schedule by mileage
What 30k, 60k, 90k and 100k really include, the items that expire on the calendar instead of the odometer, and four questions that separate a real interval from an upsell.
Template · 7 minFree car log template
Two CSV files for Excel, Sheets and Numbers — no email required — plus the formulas, including the one that handles partial fill-ups correctly.
Cost · 8 minOil change cost breakdown
Conventional (–), synthetic blend (–), full synthetic (–). DIY vs quick lube vs dealer rates, plus the four upsells to decline.
Cost · 9 minBrake pad replacement cost
Pads only (–/axle) vs pads and rotors (–/axle). Front vs rear wear, ceramic vs metallic compounds, and when rotors really need replacing.
Schedule · 8 minHow long an oil change lasts
Miles vs months vs dashboard oil monitors. Why the 3,000-mile myth survives, full synthetic realities, and the severe-service clause.
Maintenance · 9 minWhen to replace tires
The 2/32 vs 4/32 inch threshold, the penny test vs quarter test, reading DOT age codes, and uneven wear diagnostics.
Schedule · 8 minHow often to rotate tires
Intervals, rotation patterns by drivetrain (FWD vs RWD vs AWD), directional tire rules, and how to spot skipped rotations.
Maintenance · 9 minBrake pad lifespan and miles
The honest range (30k–70k miles), ceramic vs semi-metallic compounds, millimeter thickness specs, and why front pads wear first.
Schedule · 9 minSeasonal maintenance checklist
The high-impact checks for Spring, Summer, Fall, and Winter—and why winter gas mileage drops before anything is wrong with your car.
Maintenance · 8 minWhat to record in a car log book
The four load-bearing fields that matter, the friction-heavy noise people abandon, and why odometer math is king.
Money & resale
What your car actually costs per mile
The five components, a calculator using your own numbers, the national benchmark, and why running cost and total cost answer different questions.
Resale · 10 minDo service records increase resale value?
The percentages everyone quotes are unsourced. The mechanism is real: documentation removes deductions rather than adding a premium. What to keep and how to hand it over.
Money · 9 minTracking car expenses for taxes
Standard mileage rate vs actual expenses. IRS audit requirements, receipt retention, and how to choose the higher deduction.
Money · 10 minCar maintenance cost per year
Why headline averages mislead. How to calculate routine service, wear item depletion, and repair reserves based on vehicle age.
Resale · 10 minCar service history check
What VIN reports include and what they omit, how to pull national dealer records for free, and why private paper receipts beat a database.
Money · 9 minCar depreciation per mile
Why depreciation is the largest cost of car ownership, how to calculate your per-mile loss, and why older cars cost far less to drive.
Resale · 8 minKeeping car maintenance receipts
Warranty claims, tax audit windows, and resale equity. Why thermal paper receipts fade and how to build a permanent digital archive.
Resale · 8 minProving mileage when selling
Overcome odometer rollback suspicion with state inspection histories, dealer portal logs, and continuous fuel audit trails.
Maintenance · 9 minDIY vs shop maintenance cost
Job-by-job analysis of parts cost, shop labor rates, specialty tools, and which repairs you should never do in your driveway.
Cost · 9 minCatalytic converter replacement cost
OEM vs aftermarket pricing, labor hours, state emissions rules, and how to verify P0420 before spending $1,500+.
Cost · 8 minAlternator replacement cost
Parts pricing, shop labor hours, reman vs new units, and the $10 multimeter test that confirms a dead alternator.
Cost · 8 minCar battery replacement cost
Flooded vs AGM pricing, group sizes, free store installs, and why modern cars charge $100+ for battery registration.
Cost · 9 minTiming belt replacement cost
Why a $60 belt costs $900 in labor, why the water pump is mandatory, and interference engine catastrophe risks.
Cost · 8 minSpark plug replacement cost
Copper vs Iridium lifespans, why V6 engines spike labor by $300, and torque specs that prevent stripped heads.
Cost · 10 minTransmission replacement cost
Rebuilt vs remanufactured units, CVT pricing, 6-10 hours labor book time, and the 50% vehicle value repair rule.
Cost · 8 minAC compressor replacement cost
Why a black death compressor seizure requires a new condenser, R134a vs R1234yf freon costs, and clutch electrical tests.
Cost · 8 minWheel bearing replacement cost
Bolt-in hub assembly vs hydraulic press labor, growling at 45 mph, and why rust belt cars cost $200 more in labor.
Cost · 8 minStruts & shocks replacement cost
Loaded quick-struts vs bare dampers, mandatory alignment costs, and bounce tests that prove hydraulic seal failure.
Cost · 8 minStarter replacement cost
Starter motor vs solenoid vs relay, why Toyota and Honda starters hide under the intake, and bench testing rules.
Cost · 8 minRadiator replacement cost
Plastic tank crimp leaks vs aluminum core punctures, coolant flush costs, and integrated transmission cooler line risks.
Cost · 8 minWater pump replacement cost
Weep hole coolant leaks, timing belt vs serpentine labor spikes, and why you should always replace the thermostat concurrently.
Cost · 8 minFuel pump replacement cost
Dropping the gas tank vs under-seat access hatch labor, mechanical pressure tests, and why running on empty burns out pumps.
Cost · 9 minHead gasket replacement cost
Why labor requires 15 to 25 hours, cylinder head resurfacing costs, combustion gas block tests, and vehicle scrap math.
Cost · 8 minBrake caliper replacement cost
Seized guide pins vs stuck hydraulic pistons, collapsed brake hose traps, and mandatory fluid bleed labor.
Cost · 8 minClutch replacement cost
Flywheel resurfacing vs dual-mass replacement, transmission drop labor, and hydraulic throwout bearing squeals.
Cost · 7 minSerpentine belt replacement cost
Automatic belt tensioner weak springs, squealing belt triage, idler pulley bearing play, and routing diagrams.
Cost · 8 minControl arm replacement cost
Torn rubber bushings vs loose ball joints, stamped steel vs aluminum arms, and mandatory wheel alignment.
Cost · 8 minCV axle replacement cost
Torn rubber CV boots, clicking noise on sharp turns, rebooting vs complete half-shafts, and differential seal leaks.
Cost · 7 minTie rod replacement cost
Inner rack-and-pinion vs outer tie rod ends, loose steering play, and why front-end alignment is mandatory.
Cost · 7 minWheel alignment cost
Four-wheel vs thrust angle vs front-end alignment, camber/toe angles, and saving $800 tire sets from premature scrub.
Cost · 8 minBrake rotor replacement cost
Resurfacing vs new rotor replacement, minimum discard thickness specs, and warped disc steering pulsation.
Cost · 8 minValve cover gasket replacement cost
Burning oil smell on exhaust manifolds, spark plug tube seal misfires, and plastic valve cover warping.
Cost · 8 minMotor mount replacement cost
Hydraulic fluid-filled mounts vs solid rubber, heavy cabin vibration in Drive/Reverse, and engine lift tests.
Cost · 8 minOil pan gasket replacement cost
RTV silicone sealant vs rubber gaskets, subframe drop labor spikes, and stripped drain plug repairs.
Cost · 7 minThermostat replacement cost
Stuck open vs stuck closed symptoms, plastic housing crack leaks, and why DTC P0128 ruins gas mileage.
Cost · 8 minIgnition coil replacement cost
Single coil vs complete pack replacement, cylinder misfire DTCs P0300–P0308, and coil swap testing.
Cost · 8 minExhaust leak repair cost
Cracked exhaust manifolds, frayed flex pipes, rusted flanges, and cold-start ticking noise triage.
Cost · 7 minCabin air filter replacement cost
Dealership markup ($60–$90) vs DIY 5-minute swap ($15), musty AC odor triage, and activated carbon filters.
Cost · 8 minFuel injector replacement cost
Port vs direct injection (GDI) pricing, clogged vs leaking injector symptoms, and ultrasonic cleaning vs replacement.
Cost · 8 minPower steering pump replacement cost
Whining noise on turns, hydraulic fluid leak puddles, pulley press labor, and steering rack pairing.
Cost · 7 minPCV valve replacement cost
The $15 part that saves $1,500 oil seals, the physical rattle test, and excessive oil burning triage.
Cost · 8 minABS sensor replacement cost
Rust jacking on reluctor tone rings, ABS warning lights, multimeter ohm testing, and seized bolt extraction.
Cost · 8 minOxygen sensor replacement cost
Upstream wideband air-fuel sensors vs downstream monitors, rusted thread removal, and saving 15% gas mileage.
Cost · 8 minMAF sensor replacement cost
CRC MAF cleaner spray vs new sensor replacement, hot-wire contamination, and fixing lean misfire codes.
Cost · 8 minHeater core replacement cost
Sweet cabin smell, fogged windshields, floorboard coolant puddles, and 8 to 12 hours of dashboard teardown labor.
Cost · 7 minBlower motor replacement cost
Blower motor resistor failures (fan only works on high), squeaking squirrel cage bearings, and DIY footwell steps.
Cost · 7 minOil pressure sensor replacement cost
Oil pressure switch vs sending unit, false red oil warning lights, and mechanical gauge verification.
Cost · 7 minRadiator hose replacement cost
Upper vs lower radiator hose, spongy vs swollen rubber triage, spring vs worm clamps, and coolant burping.
Cost · 7 minSpark plug wires replacement cost
Carbon core high-resistance breakdown, nighttime water spray spark arc tests, and dielectric grease application.
Cost · 8 minBrake master cylinder replacement cost
Internal cup seal bypassing, spongy pedal sinking to the floor, bench bleeding, and ABS bleeding requirements.
Cost · 8 minTransmission fluid change cost
Drain and fill vs power flush controversy, pan drop filter replacements, burnt fluid diagnostics, and slip prevention.
Cost · 7 minSway bar link replacement cost
Clunking noises over low-speed bumps, torn ball socket boots, paired axle replacements, and DIY stud removal tricks.
Cost · 8 minCrankshaft position sensor replacement cost
Engine stalling when warm, no-spark cranking, tachometer dropping to zero, code P0335, and access labor.
Cost · 8 minCamshaft position sensor replacement cost
Bank 1 vs Bank 2 locations, limp mode RPM limits, extended cranking, code P0340, and timing chain stretch traps.
Cost · 8 minThrottle body replacement cost
Electronic throttle motor failure, cleaning vs replacement, surging idle, code P2119, and idle air relearn steps.
Cost · 8 minTransmission solenoid replacement cost
Single shift solenoid vs complete solenoid pack, delayed gear shifts, limp mode lock in 3rd gear, and P0750 codes.
Cost · 7 minEVAP purge valve replacement cost
Hard starts after pumping gas, stuck-open solenoid vacuum leaks, EVAP codes P0441 and P0496, and 15-minute DIY replacement.
Cost · 8 minIntake manifold gasket replacement cost
Cold morning vacuum leaks, whistling intake sounds, lean codes P0171/P0174, and plastic manifold warping.
Cost · 8 minSteering rack replacement cost
Hydraulic fluid leaks in tie rod bellows, morning sickness steering stiffness, EPS motor failures, and mandatory wheel alignment.
Cost · 8 minExhaust manifold replacement cost
Cracked cast iron runners, snapped cylinder head stud extraction, cold-start ticking, and cabin fumes.
Cost · 7 minClock spring replacement cost
Spiral cable ribbon tears, airbag warning lights, dead horn and steering wheel buttons, and centering pin rules.
Cost · 8 minFuel pressure regulator replacement cost
Ruptured rubber diaphragm fuel leaks, black exhaust smoke, extended cranking from fuel rail pressure bleed, and vacuum line sniff test.
Cost · 8 minWheel hub assembly replacement cost
Bolt-on unit hub bearings vs press-in bearings, roaring hum on highway curves, integrated ABS tone rings, and axle nut torque.
Cost · 7 minTransmission mount replacement cost
Shifting clunks between Drive and Reverse, cabin vibrations at idle, torn rubber bushings, and hydraulic fluid leaks.
Money · 10 minCommercial EV charging: costs & discovery
Level 2 vs DCFC installation costs, billing models, utility demand charge traps, and getting listed across PlugShare, Tesla NACS, and Google Maps.
Choosing tools
Best car maintenance apps in 2026
Six checks before trusting one with a decade of history, where the well-known apps stand as of July 2026, and how to read a privacy label in 60 seconds.
Tools · 9 minBest free car maintenance app
What 'free' costs in this category: ads, account locks, data brokerage, and export walls. How each business model operates.
Tools · 8 minFuel log app vs spreadsheet
Portability vs entry friction. Why spreadsheets win on ownership but fail at the pump, and the decision rule to pick between them.
SwitchingLeaving Fuelly
Export your fuel history in three steps and import it without losing partial fill-ups, units, or years of odometer readings.
SwitchingLeaving Simply Auto
Same three steps for Simply Auto export — including what its MPG method did to your historical numbers.
SwitchingLeaving CARFAX Car Care
No export button, DIY work that never counted, records on someone else server. How to start a maintenance log you actually own.
Privacy · 9 minCar app privacy & data tracking
What vehicle apps infer from fuel logs, how brokers like LexisNexis hike insurance rates, and why local iCloud storage matters.
Tools · 9 minBest EV charging apps (2026)
PlugShare vs ABRP vs ChargePoint vs Tesla app, crowdsourced reliability scores, road trip battery planning, and home charging math.
Diagnosis
Squeaking when you brake
Cheapest-first triage: moisture, dust, glaze, then the wear indicator. Says plainly which noises are a same-day shop visit.
Diagnosis · 9 minCar shakes when you brake
Warped rotors are the popular answer and often the wrong one. Lug nuts, pad deposits, and worn suspension first.
Diagnosis · 8 minCheck engine light after a fill-up
The loose gas cap really is the common cause. How to confirm it, which EVAP codes can wait, and what means do not drive.
Diagnosis · 9 minBurning smell from the car
Six smells, six causes. Sweet coolant and hot wiring are the ones that mean stop. New brakes can smell like a shop for a few miles.
Diagnosis · 8 minWon't start — just a click
Single click versus rapid clicking are different faults. Battery and terminals before anyone sells you a starter.
Diagnosis · 9 minEngine idling rough
Vacuum leaks, dirty throttle bodies, worn plugs, and ignition coils. Sorted by repair cost and how to spot the early fuel economy drop.
Diagnosis · 8 minCar AC not blowing cold
Why DIY recharge cans do more damage than good. Cabin air filter, condenser debris, compressor clutch, and how to spot a real refrigerant leak.
Diagnosis · 8 minBattery keeps dying overnight
Parasitic draw versus battery end of life versus a failing alternator. A multimeter test anyone can do, and why battery age settles it.
Diagnosis · 8 minSteering wheel vibrates at speed
Wheel balance, tire flat-spotting, bent rims, and brake runout. Why alignment does not fix vibration and what the speed tells you.
Diagnosis · 7 minOil light came on
Red oil pressure light versus amber oil level light. Why pressure means pull over and shut down immediately, and what to check on the dipstick.
Diagnosis · 8 minWhite smoke from exhaust
Tell cold morning condensation from a blown head gasket. Dissipation speed, sweet coolant smell, and how to inspect the radiator tank.
Diagnosis · 7 minTPMS light won't go off
Why the tire pressure light stays on after inflating. Drive cycle resets, the forgotten spare tire sensor, and 7-year battery lifespans.
Never lose another repair receipt or fuel log
Keep your complete service history, real full-tank MPG, and diagnostic records organized on your iPhone. Carvico alerts you before service is overdue and gives you verified PDF records when you sell — 100% private on your own iCloud with zero ads.
