Spark Plugs
Find Spark Plugs for your vehicle
Enter your reg and we'll show you only parts that fit — no guesswork.
Don't know your reg? Find manually
- ✓ Free delivery on orders over £40
- ✓ UK stock, dispatched from Northampton
- ✓ Filtered to your specific vehicle from DVLA data
Browse all Spark Plugs
- Bosch Engine Spark Plug 0 242 140 572 £17.99
- Bosch Engine Spark Plug 0 242 140 565 £17.99
- Bosch Engine Spark Plug 0 242 135 595 £16.99
- Denso Engine Spark Plug VW22A £24.99
- Bosch Spark Plug Connector 1 354 489 085 £30.99
- Bosch Spark Plug Connector 0 356 100 100 £29.99
- Bosch Spark Plug Connector 0 356 100 107 £29.99
- Bosch Spark Plug Connector 0 356 351 053 £47.99
- Bosch Spark Plug Connector 0 356 150 022 £34.99
- Bosch Spark Plug Connector 0 356 100 030 £36.99
- Bosch Engine Spark Plug 0 242 242 501 £11.99
- Bosch Engine Spark Plug 0 242 250 518 £10.99
- Bosch Engine Spark Plug 0 242 245 576 £12.99
- Bosch Engine Spark Plug 0 242 245 590 £10.99
- Bosch Engine Spark Plug 0 242 240 706 £12.99
- Bosch Engine Spark Plug 0 242 245 536 £6.99
- Bosch Engine Spark Plug 0 242 245 585 £13.99
- Bosch Engine Spark Plug 0 242 245 571 £12.99
- Bosch Engine Spark Plug 0 242 240 665 £11.99
- Bosch Engine Spark Plug 0 242 240 707 £9.99
- Bosch Engine Spark Plug 0 242 240 715 £20.99
- Bosch Engine Spark Plug 0 242 240 654 £10.99
- Bosch Engine Spark Plug 0 242 240 619 £11.99
- Bosch Engine Spark Plug 0 242 240 691 £12.99
About Spark Plugs
NN4 Online stocks a wide range of spark plugs from established manufacturers including Bosch and Denso. Enter your registration above and we'll narrow the list to spark plugs that match your vehicle in the TecDoc catalogue. We always recommend confirming the part dimensions against your existing component before fitting, as specifications can vary between trim levels and engine variants.
All stock dispatches from our Northampton warehouse with free standard delivery on orders over £40 to most UK mainland locations. Browse the full spark plugs catalogue below, or use the registration lookup to filter to parts matched to your vehicle.
Frequently asked
How do I know a part will fit my car?
Enter your registration above and we cross-check against the TecDoc catalogue to narrow the list to spark plugs listed against your vehicle. Specifications can still vary between trim levels and engine variants, so we recommend confirming the part dimensions against your existing component before fitting.
What brands do you stock?
We stock established manufacturer brands sourced through trade channels. The brand row at the bottom of this page shows which manufacturers we carry for spark plugs. We don't sell unbranded parts.
How quickly will my order arrive?
Most orders dispatch from our Northampton warehouse within 1–2 working days. Free standard delivery on orders over £40 to most UK mainland locations.
What if the part doesn't fit?
Please check our returns policy for the current terms. If you're unsure about fitment for your specific vehicle variant, please contact our team before ordering using the details at the bottom of the site.
Can I check fitment before ordering?
Yes — every product page shows whether the part is listed against your selected vehicle. Where multiple sizes exist for the same vehicle, the dimensions are shown so you can compare against your existing part. If you're unsure, contact our team for help confirming the right option.
About Spark Plugs
Our spark plugs range is built from established UK suppliers and trusted aftermarket brands. Each product is mapped against OE/OEM references and TecDoc ktype data so the reg-lookup above filters to only the parts that fit your specific make, model, engine and trim.
Enter your registration to see exact-fit options — or browse by brand using the tiles above. The full catalogue covers most major makes and models on UK roads, with same-business-day dispatch on stock items ordered before 2pm.
Engine and cooling system parts
Engine and cooling parts span a wide spectrum — timing belts and chains, water pumps, alternators, starters, gaskets and seals. Some are service-interval items (timing belt every 5-10 years or 60-100k miles depending on engine), others are catch-it-early items where small failures can lead to bigger ones if ignored.
Common engine warning signs
- Whining or rattling from the front of the engine — failing belt tensioner or alternator bearing.
- Coolant loss with no visible leak — head gasket, hose or water pump seal.
- Charging warning light or dim headlights at idle — alternator output dropping.
- Slow cranking on cold mornings — starter motor or battery, both worth checking.
Don't postpone a timing-belt service
The biggest avoidable engine failure on the UK fleet is timing-belt overrun. If your service book is missing or the previous owner's record is unclear, get it checked — replacing a belt costs a few hundred pounds; replacing the engine after a belt snap on an interference engine runs into thousands.
Why buy from NN4 Online
- Reg-lookup fitment — see only the parts mapped to your specific vehicle.
- UK warehouses — most stock items dispatch same business day on orders before 2pm.
- Established brands — the brand tiles above are the full list available in this category.
- Standard returns — handled per our returns policy linked in the footer.