What’s a knock sensor and why does it matter?
If you’re running your car around Hamilton, whether it’s early school runs in Rototuna, getting across to Te Awamutu or just trekking down Victoria Street for work, you want that engine running sweet as. But there’s a wee part under the bonnet most folks barely think about: the knock sensor.
So, what’s it do? Basically, the knock sensor is your car’s early warning system. When you get a bit of dodgy fuel at the pumps out Morrinsville way, cop a pothole on Ulster Street or hit those rough speed bumps in Melville, sometimes your engine can start to pre-detonate (that’s what we call ‘knocking’).
The knock sensor picks up those dodgy vibrations and tells your car’s computer (the ECU) to fix things up before any real damage is done. So, it helps with performance, saves fuel, and keeps the engine from wearing out too quick. Doesn’t matter if you’re driving a Toyota Wish, Nissan Leaf, Honda Jazz or even something like an old Peugeot 308 – they’ve all got ‘em.
What happens when your knock sensor packs it in?
We see quite a few folks from Cambridge and Huntly coming in after their check engine lights pop up, and honestly it’s often a knock sensor playing up. It’s a tiny bit, but it can cause a lot of hassle. Here’s what you might notice:
Check engine light on – If your light’s come on and you’re not sure why, it could well be this. Sometimes, after a cold winter start in Fairfield or a run up Dinsdale hill, you’ll notice it more.
Sluggish acceleration – Your car won’t pull away as quick, especially when you stomp on it getting onto SH1. We just sorted a Hyundai i30 for a customer from Ngaruawahia – it was crawling off the lights.
Burning more fuel – If you keep having to top up at gull out in Chartwell, the car might be getting lazy on fuel. Knock sensors play a big part in making sure your engine runs as efficiently as it should.
Failed emissions or WOF – A crook knock sensor can bump up your emissions, making your car more likely to fail its WOF emissions test. Common with Mazdas and Subarus we’ve had from around Horotiu.
Getting your knock sensor replaced in Hamilton
If you think your knock sensor’s dodgy, don’t leave it. It’ll only get worse – and you don’t want a big repair bill down the track or end up stuck waiting for a tow out by Tamahere.
Pop into Grimmer Motors, right here in Hamilton, and one of our techs can give your engine a proper once-over. If the knock sensor’s the culprit, we’ll swap it out for a new one, no dramas. We do plenty for all sorts – hybrids like the Prius, Suzuki Swifts, even the odd Kia Carnival or Mercedes C-Class.
While you’re here, we can sort out your regular car service Hamilton-style, an oil change or scan the whole car for other issues. Good idea to keep on top of the little stuff, especially with NZ conditions being a real mix – muggy summer, freezing foggy mornings, heaps of stop-start traffic over at The Base, and those rough back roads out to Raglan. Hamilton driving isn’t easy on cars but keeping sensors and basic bits sorted means less hassle for you.
If you’re worried about your engine, or just want a good once-over before your next WOF Hamilton test, give us a bell. We’re always keen for a chat and happy to help – whether you know your way around an engine or haven’t got a clue.