Skip to main content
CP247
All systems

Car Parts Buying Guides

Not sure which part you need? Our buying guides explain what to look for, when to replace, and how to choose the right component for your vehicle.

Brake Pads Buying Guide

How to choose the right brake pads — signs of wear, organic vs ceramic vs semi-metallic, and replacement tips.

Read guide

Brake Discs Buying Guide

Vented, solid, or drilled? Learn when to replace brake discs, minimum thickness, and how to pick the right type.

Read guide

Oil Filter Buying Guide

Why oil filters matter, how often to change them, and how to find the right one for your engine.

Read guide

Air Filter Buying Guide

Signs of a clogged air filter, paper vs cotton, and how replacing your air filter improves fuel economy.

Read guide

Spark Plugs Buying Guide

Copper, platinum, or iridium? Understand heat ranges, gap settings, and when to replace spark plugs.

Read guide

Wiper Blades Buying Guide

Conventional, flat, or hybrid wiper blades — fitting types, sizing, and when to swap them out.

Read guide

Shock Absorbers Buying Guide

Twin-tube vs monotube, gas vs oil — signs your shocks are worn and how to choose replacements.

Read guide

Car Battery Buying Guide

CCA ratings, battery group sizes, AGM vs EFB — everything you need to choose the right car battery.

Read guide

Timing Belt Buying Guide

Replacement intervals, interference vs non-interference engines, and why timing belt failure is catastrophic.

Read guide

Clutch Kit Buying Guide

Full kit vs disc only, DMF inspection, and signs your clutch is slipping or worn.

Read guide

Headlight Bulbs Guide

H1, H4, H7 — find the right bulb type, understand LED upgrades, and learn why you should replace in pairs.

Read guide

Cabin Filter Guide

Standard vs activated carbon cabin filters — replacement intervals, symptoms, and allergy benefits.

Read guide

Control Arms Guide

What control arms do, symptoms of worn bushings and ball joints, and when to replace them.

Read guide

Wheel Bearings Guide

Humming, droning, grinding — diagnose a bad wheel bearing and understand replacement options.

Read guide

Engine Thermostat Guide

Stuck open or stuck closed? Learn how thermostats work and when to replace yours.

Read guide

Alternator Guide

Alternator vs battery — how to diagnose charging faults and choose the right replacement.

Read guide

Radiator Guide

Signs of a leaking radiator, repair vs replacement, and how to prevent overheating.

Read guide

Starter Motor Guide

Clicking when turning the key? Diagnose starter motor issues and find the right replacement.

Read guide

Water Pump Guide

Belt-driven vs electric water pumps — failure symptoms, replacement intervals, and timing belt links.

Read guide

Ignition Coils Guide

Misfires and rough idle? How to identify a faulty coil with an OBD scanner and decide on replacement.

Read guide

Fuel Pump Buying Guide

Electric and mechanical fuel pumps — failure symptoms, replacement advice, and how to choose the right pump for your vehicle.

Read guide

Lambda Sensor Buying Guide

Pre-cat and post-cat oxygen sensors — diagnostic codes, emissions impact, and choosing direct-fit vs universal.

Read guide

Drive Belt Buying Guide

Serpentine and auxiliary belt replacement — signs of wear, tensioner advice, and what happens when a belt snaps.

Read guide

Brake Caliper Buying Guide

Seized or leaking brake calipers — symptoms, slide pin maintenance, and when to repair vs replace.

Read guide

Turbocharger Buying Guide

Turbo failure symptoms, oil supply essentials, and choosing between new and remanufactured turbochargers.

Read guide

EGR Valve Buying Guide

Exhaust gas recirculation explained — carbon build-up causes, cleaning vs replacement, and emissions inspection rules.

Read guide

Mass Air Flow Sensor Guide

MAF sensor faults — P0100 codes, cleaning tips, and how a faulty MAF affects fuel economy and performance.

Read guide

Fuel Injector Buying Guide

Petrol and diesel injectors — misfire diagnosis, injector coding, and maintenance tips for long injector life.

Read guide

Catalytic Converter Buying Guide

P0420 codes, emissions failures, and type-approval rules — how to choose a legal replacement catalytic converter.

Read guide

Steering Rack Buying Guide

Hydraulic and electric steering racks — leak diagnosis, remanufactured options, and alignment after replacement.

Read guide

CV Joint Buying Guide

Clicking on turns? Diagnose CV joint and driveshaft faults — boot replacement vs complete shaft options.

Read guide

Suspension Spring Buying Guide

Coil spring breakage, sagging ride height, and corrosion — replacement advice and spring types.

Read guide

Engine Mount Buying Guide

Excessive vibration and clunking? Diagnose worn engine mounts — rubber vs hydraulic and replacement tips.

Read guide

Glow Plug Buying Guide

Diesel cold-start problems — glow plug failure symptoms, removal tips for seized plugs, and replacement advice.

Read guide

ABS Sensor Buying Guide

ABS and ESC warning lights — wheel speed sensor diagnosis, reluctor ring checks, and replacement guide.

Read guide

Tie Rod End Buying Guide

Loose steering and inspection failures — tie rod end symptoms, replacement tips, and alignment essentials.

Read guide

Window Regulator Buying Guide

Electric window stuck or fallen? Cable and rail regulator types, motor replacement, and fitting guide.

Read guide

Ball Joint Buying Guide

Clunking suspension and inspection failures — press-fit vs bolt-on ball joints, wear signs, and replacement advice.

Read guide

Exhaust System Buying Guide

Blowing exhaust, rust, and inspection failures — section-by-section replacement, mild steel vs stainless options.

Read guide

Power Steering Pump Buying Guide

Whining noise and heavy steering — pump failure diagnosis, system flushing, and fluid specification guide.

Read guide

Clutch Disc Buying Guide

Organic vs ceramic clutch disc materials — signs of slipping, juddering, and when to replace alongside the pressure plate.

Read guide

Flywheel Buying Guide

Single-mass vs dual-mass flywheel — DMF failure symptoms, resurfacing limits, and replacement cost factors.

Read guide

Drive Shaft Buying Guide

Vibrations at speed and clicking on turns — how to diagnose drive shaft faults and choose between new and reconditioned units.

Read guide

Differential Buying Guide

Whining rear end and limited-slip basics — differential oil types, common faults, and replacement vs rebuild options.

Read guide

Door Handle Buying Guide

Broken or stiff door handle? Interior vs exterior types, common failure points, and fitting tips for all car makes.

Read guide

Wing Mirror Buying Guide

Electric, heated, and folding wing mirrors — glass replacement vs full unit, and colour matching tips.

Read guide

Bumper Buying Guide

Front and rear bumper replacement — primed vs painted, sensor cutouts, and how to ensure a perfect fit.

Read guide

Headlight Housing Buying Guide

Halogen, xenon, and LED headlight units — lens clarity, projector vs reflector, and E-mark compliance.

Read guide

Tail Light Buying Guide

Cracked or foggy rear lights? OEM vs aftermarket tail light units, bulb types, and MOT compliance.

Read guide

Wiper Motor Buying Guide

Front and rear wiper motor faults — slow wipers, intermittent operation, and motor replacement steps.

Read guide

Expansion Tank Buying Guide

Coolant loss and cracked tanks — how to spot a failing expansion tank, pressure cap types, and replacement guide.

Read guide

Intercooler Buying Guide

Air-to-air vs air-to-water intercoolers — boost leak diagnosis, core damage signs, and upgrade options.

Read guide

Radiator Hose Buying Guide

Upper and lower radiator hose replacement — swelling, cracking, and how to choose the right material and size.

Read guide

DPF Filter Buying Guide

Diesel particulate filter regeneration, blockage symptoms, and when cleaning vs replacement makes financial sense.

Read guide

Exhaust Manifold Buying Guide

Cracked manifold symptoms, exhaust leaks, and cast iron vs stainless steel manifold replacement options.

Read guide

Muffler Buying Guide

Rear, middle, and front muffler types — noise regulations, corrosion, and universal vs direct-fit replacements.

Read guide

Horn Buying Guide

Disc, fanfare, and air horns — wiring basics, relay upgrades, and MOT requirements for horn operation.

Read guide

Window Motor Buying Guide

Electric window motor diagnosis — slow operation, clicking noises, and motor vs regulator replacement.

Read guide

Ignition Switch Buying Guide

No-start faults, intermittent power loss, and key won't turn — how to diagnose and replace a faulty ignition switch.

Read guide

Throttle Body Buying Guide

Electronic throttle body cleaning vs replacement — idle problems, throttle position sensor faults, and adaptation.

Read guide

Fuel Tank Buying Guide

Rust, leaks, and fuel contamination — steel vs plastic fuel tanks, capacity specs, and replacement precautions.

Read guide

Gearbox Mount Buying Guide

Vibration, clunking on gear change, and excessive movement — how to diagnose worn gearbox mounts and choose replacements.

Read guide

Clutch Slave Cylinder Buying Guide

Soft pedal, fluid loss, and gear selection issues — slave cylinder diagnosis, bleeding procedure, and replacement advice.

Read guide

Clutch Master Cylinder Buying Guide

Clutch pedal sinks to the floor? Master cylinder leak symptoms, brake fluid compatibility, and replacement steps.

Read guide

Anti-Roll Bar Link Buying Guide

Knocking over bumps? Anti-roll bar drop link wear symptoms, replacement tips, and how they affect handling.

Read guide

Anti-Roll Bar Bush Buying Guide

Worn anti-roll bar bushes cause clunks and body roll — polyurethane vs rubber, sizing, and fitting guide.

Read guide

Top Mount Buying Guide

Creaking on turns and knocking over bumps — strut top mount bearing failure, symptoms, and replacement with shocks.

Read guide

Brake Hose Buying Guide

Spongy pedal and MOT failures — rubber vs braided steel brake hoses, swelling diagnosis, and replacement intervals.

Read guide

Brake Drum Buying Guide

Rear brake drum wear limits, scoring diagnosis, and when to machine vs replace — a guide for drum brake vehicles.

Read guide

Handbrake Cable Buying Guide

Handbrake won't hold on hills? Cable stretch, seized mechanisms, and replacement tips for parking brake cables.

Read guide

Blower Motor Buying Guide

No air from the vents? Blower motor failure diagnosis, resistor module faults, and replacement guide.

Read guide

Heater Resistor Buying Guide

Fan only works on max speed? Heater blower resistor faults explained — testing, symptoms, and replacement steps.

Read guide

Door Lock Actuator Buying Guide

Central locking not working on one door? Actuator motor faults, wiring issues, and step-by-step replacement guide.

Read guide

Brake Master Cylinder Buying Guide

Spongy or sinking brake pedal? How to diagnose a failing brake master cylinder, bleed the system, and choose the right replacement.

Read guide

Brake Shoe Set Buying Guide

Rear drum brake shoes — lining materials, wear limits, self-adjusting mechanisms, and how to replace brake shoes safely.

Read guide

Brake Fluid Buying Guide

DOT 3, DOT 4, DOT 5.1 explained — dry and wet boiling points, hygroscopic ageing, and when to flush your brake fluid.

Read guide

Clock Spring (Airbag Spiral Cable) Buying Guide

Airbag warning light, horn failure, and cruise control loss — how a faulty clock spring is diagnosed and what to check before replacement.

Read guide

Tyre Pressure Monitoring Sensor (TPMS) Buying Guide

TPMS warning light, direct vs indirect systems, and what to do when replacing tyres — choosing compatible TPMS sensors.

Read guide

Crankshaft Position Sensor Buying Guide

No-start, misfires, and sudden engine cut-out — how the crankshaft sensor works, fault codes, and choosing the correct replacement.

Read guide

Coolant Temperature Sensor Buying Guide

Incorrect temperature gauge, poor fuel economy, and cooling fan issues — diagnosing a faulty coolant temperature sensor and selecting a replacement.

Read guide

Camshaft Position Sensor Buying Guide

P0340 fault codes, misfires, and rough running — how camshaft sensors control valve timing and when to replace them.

Read guide

Air Conditioning Compressor Buying Guide

No cold air, clutch not engaging, and seized compressors — A/C compressor types, oil charging requirements, and new vs remanufactured options.

Read guide

Intake Air Hose Buying Guide

Cracked or collapsed intake hoses cause poor performance and false MAF readings — how to inspect, diagnose, and replace rubber air intake ducting.

Read guide

Sports Air Filter Buying Guide

Cotton gauze vs foam vs paper performance filters — real-world power gains, oiling intervals, and whether a sports air filter improves fuel economy.

Read guide

Fuel Filter Buying Guide

Petrol and diesel fuel filters — blockage symptoms, in-line vs in-tank designs, replacement intervals, and water-separator maintenance for diesel.

Read guide

Fuel Pressure Regulator Buying Guide

Hard starts, black smoke, and fuel smell — how a fuel pressure regulator works, failure symptoms, and replacing it without damaging injectors.

Read guide

Timing Chain Kit Buying Guide

Chains vs belts, tensioner rattle on cold start, and stretched chain symptoms — when to replace a timing chain kit and what the job involves.

Read guide

Water Pump and Timing Belt Kit Buying Guide

Why replace the water pump with the timing belt? Combined kit advantages, service intervals, and what to check when buying an all-in-one kit.

Read guide

Coolant Flange Buying Guide

Coolant flanges, thermostat housings, and outlet pipes — plastic vs aluminium, common failure modes, and correct sealant for leak-free installation.

Read guide

Engine Oil Cooler Buying Guide

Water-cooled vs air-cooled oil coolers, oil-in-coolant mixing symptoms, and how to choose and fit a replacement oil cooler without disturbing the coolant system.

Read guide

Steering Column Buying Guide

Collapsible, tilt, and telescopic steering columns — fault symptoms, MOT implications, and choosing between complete assemblies and individual column components.

Read guide

Steering Angle Sensor Buying Guide

ESC and traction control faults caused by steering angle sensor errors — calibration requirements, fault codes, and replacement guide.

Read guide

Manual Gearbox Buying Guide

Crunching gears, oil leaks, and whining noises — diagnosing manual gearbox faults, the case for reconditioned vs new units, and oil specification.

Read guide

Automatic Gearbox Buying Guide

Slipping, harsh shifts, and TCU faults — how automatic transmissions fail, fluid service intervals, and when to rebuild vs replace your gearbox.

Read guide

Clutch Release Bearing Buying Guide

Squealing when pressing the clutch pedal — identifying a worn release bearing, replacing it alongside the clutch kit, and avoiding premature failure.

Read guide

Suspension Strut Buying Guide

MacPherson struts vs separate shock and spring — when to replace as a complete assembly, loaded vs bare struts, and corner-by-corner replacement tips.

Read guide

Boot and Bonnet Gas Strut Buying Guide

Tailgate or bonnet not staying up? How to measure force rating, strut length, and ball-end fittings — and why cheap gas struts fail quickly.

Read guide

CV Boot Buying Guide

Split or cracked CV boots lead to joint failure — how to spot grease flinging, boot types and sizes, and replacing a boot without removing the driveshaft.

Read guide

Engine Oil Pump Buying Guide

Low oil pressure warning, noisy engine, and bearing wear — oil pump failure causes, pressure testing, and what to do when the pick-up tube is clogged.

Read guide

Head Gasket Buying Guide

Overheating, milky oil, and white exhaust smoke — identifying a blown head gasket, multi-layer steel vs composite types, and what the repair involves.

Read guide

Crankcase Ventilation (PCV) Valve Buying Guide

Oil leaks, high oil consumption, and rough idle — how the PCV valve prevents pressure build-up, clogging symptoms, and easy replacement steps.

Read guide

Intake Manifold Swirl Flap Buying Guide

Broken plastic swirl flaps can enter diesel engines and cause catastrophic damage — fault codes, removal options, and choosing a replacement kit.

Read guide

Oil Separator (Catch Can) Buying Guide

Excessive oil consumption and carbon build-up on intake valves — how an oil separator or catch can works, fitting guide, and which engines benefit most.

Read guide