Parts for your 2006 Toyota Ist-Sump plug washers

2006 Toyota Ist sump plug washers — fitted, important, and easy to service

For the 2006 Toyota Ist (NCP60/NCP61 with the 1NZ‑FE engine), a sump plug washer is absolutely used and relevant. Toyota’s Electronic Parts Catalogue lists a replaceable aluminium crush gasket for the engine oil drain plug (commonly supplied as 90430‑12031 for the 12 mm plug), and Toyota’s repair procedures in TIS specify replacing the gasket at each oil change. Independent service manuals for related platforms (such as Scion xA and Yaris with the 1NZ‑FE) echo the same requirement. That means this little ring is a normal service item on the Ist, not an optional extra.

What does it do? The sump plug washer is a soft, single‑use seal that crushes slightly when the drain plug is torqued, creating a reliable seal between the plug and the oil pan. It prevents those annoying weeps that leave a spot on the driveway and helps keep oil where it belongs. On the 2006 Toyota Ist, the washer pairs with the M12 x 1.25 drain plug and is designed to be replaced whenever the plug comes out.

Best practice for owners and workshops across Australia and New Zealand is to treat the washer as a consumable. Reusing an old one can lead to micro‑leaks, especially once it’s been flattened from the previous service. Genuine Toyota or high‑quality aftermarket copper or aluminium washers both do the job, the key is the correct size and a fresh, undamaged sealing face.

• Replace the washer at every oil change (typically every 10,000–15,000 km or 6–12 months, depending on service schedule and conditions).
• Clean the mating surface on the sump before refitting the plug.
• Tighten the drain plug to the specified torque. For the 1NZ‑FE, Toyota service data commonly specifies about 27 N·m (check your model‑specific manual).
• After the first drive, have a quick look underneath for any signs of seeping.

If the plug or pan face is nicked or burred, even a new washer might not seal perfectly, so inspect and remedy any damage. Keeping a small stash of the correct 12 mm washers on the shelf makes life easy at service time — they’re inexpensive and save headaches later. Referencing Toyota’s EPC and TIS for the 2006 Ist confirms this washer is part of the standard oil change procedure and is intended to be renewed each time.

Popular questions about 2006 Toyota Ist sump plug washers

What size sump plug washer does a 2006 Toyota Ist use?

For the 2006 Toyota Ist with the 1NZ‑FE engine, the sump plug uses a 12 mm crush washer paired to an M12 x 1.25 drain plug. Toyota commonly supplies this as gasket part number 90430‑12031.

Because there can be production variations, it’s smart to confirm by VIN or measure the existing plug before stocking up, but for the NCP60/NCP61 Ist, the 12 mm gasket is the go‑to.

How often should the sump plug washer be replaced on a 2006 Toyota Ist?

Replace it at every oil change. The washer is designed to crush once and provide a perfect seal, so reusing it increases the chance of minor leaks.

If the plug has been removed for any reason between services, fit a new washer again when refitting.

What torque should the drain plug be tightened to, and can the washer be reused?

For the 1NZ‑FE in the 2006 Ist, a typical factory torque for the drain plug is about 27 N·m. Over‑tightening can distort threads or the pan, while under‑tightening risks seepage.

Don’t reuse the washer. Fit a fresh 12 mm crush washer each time the plug is removed to maintain a tidy, leak‑free seal.