Denso Iridium Power IW24 Spark Plug

Denso Iridium Power IW24 is a vehicle-specific replacement spark plug with an iridium centre electrode. The listing gives fitting dimensions and installation torque, but compatibility should be confirmed against the vehicle and engine before purchase.

At a glance

The listing specifies a 0.7 mm gap and a 0.4 mm iridium centre electrode.
A 5,000 ohm resistor is specified to reduce electromagnetic noise that may affect electronic devices.
The terminal nut is described as removable for installations that do not require one.
The manufacturer describes a burnished nickel-plated housing. Its corrosion-resistance claim excludes low-heat-range types.

Price

£11.59Save 17%

Reference price: ~~£13.99~~

Price checked: 12 Nov 2026

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Often bought together

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Pros and cons

Pros

The listing supplies thread length, diameter and tightening torque, which can help when checking a replacement plug against service information.
The iridium electrode and integrated resistor are concrete design details for buyers seeking this plug configuration.

Technical specifications

17 specifications

Identity
Brand	Denso
Model	iw24
Vehicle fit type	Vehicle Specific Fit
Vehicle type	Car

Electrode and materials
Core material	Iridium
Gap size	0.7 Millimeters
Electrode configuration	IW24 \| 1 - Earthed Electrode \| Tightening Torque (Nm): 22 \| Diamiter (mm) : 14 \| Thread Length (mm): 19

Dimensions and installation
Thread size	RM
Weight listed	0.06 Kilograms
Centre electrode diameter	0.4mm diameter iridium alloy center electrode
Tightening torque	22
Diameter	14
Thread length	19

Electrical details
Resistor specification	5,000 ohm monolithic resistor specification

Pack and origin
Number of packs	1
Country of origin	Japan
Manufacturer warranty description	2 year manufacturer

What to know before buying

Listing details to confirm

The broad vehicle fitment claim does not establish compatibility with a particular vehicle or engine. Verify the IW24 part number and installation requirements against the vehicle or engine maker's specifications before fitting. The listing describes the plug as suitable for cars while also recommending Iridium Power plugs for motorcycle engines, and gives a thread size of RM alongside a diameter of 14 mm without clarifying their relationship. Confirm these listing details for the intended application. The listed corrosion claim excludes low-heat-range types.

What’s in the box

Included

1 x Iridium Power Spark Plug

Who is it for?

A good fit for

Buyers replacing a plug after confirming IW24 is specified for their exact vehicle or engine.
Those who want an iridium-electrode plug with listed gap, thread length and torque details.

Less suited to

Anyone choosing a spark plug solely from the vehicle-brand list in the title without confirming exact engine fitment.
Buyers who require verified performance gains or a confirmed service-life figure, neither of which is established here.

Denso Iridium Power IW24 Spark Plug · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.6 / 5 · 10 ratings

5 stars72%72%
4 stars15%15%
3 stars13%13%
2 stars0%0%
1 star0%0%

The supplied evidence contains aggregate ratings but no customer comments, so it does not establish specific praised features or complaints. The overall rating distribution is mostly five-star with some three- and four-star ratings, but the small sample limits what can be concluded about fitment or performance.

Frequently asked questions

Will the IW24 fit my vehicle?

The listing describes a vehicle-specific fit and names several vehicle brands, but does not establish fitment for every model or engine. Confirm the IW24 against the vehicle maker's parts information before ordering.

What installation measurements are listed?

The listing gives a 0.7 mm gap, 14 mm diameter, 19 mm thread length and tightening torque of 22 Nm. Check the correct requirements for your engine before installation.

Does it include a terminal nut?

The manufacturer feature text says a terminal nut is attached and can be removed where the installation does not require one. It notes that certain other plug types have solid, non-removable nuts, but does not identify IW24 among them.

What is stated about the warranty?

The listing states “2 year manufacturer”. It does not provide further warranty terms here.