DENSO Iridium TT Spark Plug 4 Pack • IT16TT

Suitable for Mazda MX-5 Mk3 / Mk3.5 / Mk3.75 (NC) 1.8 petrol models. This listing supplies a complete pack of 4 spark plugs.

DENSO IT16TT is an Iridium TT spark plug suitable for the Mazda applications listed below. For the MX-5 NC, this plug is specified for the 1.8-litre engine; the 2.0-litre NC uses a different spark plug specification.

DENSO's Iridium TT design combines an ultra-fine 0.4 mm iridium-alloy centre electrode with a 0.7 mm needle-type platinum-alloy ground electrode. The fine Twin Tip arrangement reduces obstruction around the initial spark and is designed to provide dependable ignitability and stable combustion.

Product Specifications

• Brand: DENSO
• Product range: Iridium TT
• Part number: IT16TT
• DENSO secondary / long part number: 267700-8230
• DENSO trade number: 4713
• DENSO specification number: IT13
• GTIN / EAN: 042511047136
• Plug type: Iridium TT spark plug
• Seat type: Taper seat
• Centre electrode: 0.4 mm iridium alloy
• Ground electrode: 0.7 mm needle-type platinum alloy
• DENSO heat range: 16
• Thread diameter: 14 mm
• Thread size: M14 x 1.25
• Thread reach: 17.5 mm
• Hex / spanner size: 16 mm
• Spark gap: 1.0 mm
• Projection: 1.5 mm
• Spark position: 3.0 mm
• Ground electrode height: 6.2 mm
• Terminal type: Solid SAE
• Resistor: 5 kΩ
• Recommended tightening torque: 22 Nm
• Quantity required per MX-5: 4
• Quantity supplied: 4 spark plugs

Typical Reasons for Replacement

Spark plugs are routine ignition-system service components and may require replacement because of normal electrode wear, accumulated service mileage or scheduled maintenance. Worn or unsuitable plugs can contribute to difficult starting, an uneven idle or ignition misfire, although these symptoms can also have other causes and should be correctly diagnosed.

Fitment Advice

For Mazda MX-5 applications, IT16TT is for the 1.8-litre Mk3 / NC engine. Do not use this listing for the 2.0-litre NC simply because the plug appears physically similar.

Replacing all four plugs together is recommended. Ensure the plug wells are clean before removing the old plugs, start each replacement plug carefully by hand to minimise the risk of cross-threading and tighten using the appropriate service procedure.

The spark plugs are supplied to the stated DENSO specification. Do not alter the plug gap unless the applicable Mazda or DENSO service information specifically requires it.

For imported, modified or previously repaired cars, matching the part number or component style on the part being replaced is recommended.

Other Items to Consider

• Ignition coils
• Engine air filter
• Engine oil and oil filter when completing a routine service

Useful Tools / Consumables

• 16 mm spark plug socket
• Suitable extension and ratchet
• Torque wrench
• Compressed air or suitable cleaning equipment for the spark-plug wells

Difficulty Guide

DIY Difficulty: Easy to Moderate. Spark-plug replacement is a routine service operation, but correct plug identification, careful thread engagement and appropriate tightening torque are important.

Why DENSO?

DENSO is a long-established ignition manufacturer with extensive automotive engineering experience. Its Iridium TT spark plugs use a fine 0.4 mm iridium centre electrode together with a 0.7 mm platinum Twin Tip ground electrode, providing a compact spark area and dependable ignition performance.

What's in the Box?

• 4 x DENSO IT16TT Iridium TT spark plugs

Installation Notes

Install only into a cool engine. Start each plug carefully by hand before tightening, avoid cross-threading and use the appropriate torque procedure. Do not over-tighten the plugs or apply additional thread treatments unless specifically required by the applicable service information.