I changed mine at 125K and then at 250K. Still on the third pair at 360K. The changes were all preventive and none had failed. I would not be surprised if those have lasted for 200K or more for anyone.
193,000. They should have been changed at 120,000 but the dealer doing the service for me must have overlooked it. -Graeme- 2004 Prius with >190,000 miles. Sent ?.
If you look closely at the service manual, it says to change them at 120,000 miles but then in small print says the interval in carb states states is 150,000. That suggests that the 120,000 interval is due to emission standards in non carb states and that the plugs can last at least 150,000. Of course, no harm in changing at 120,000. From the service manual:
FWIW It is an old recommendation to remove and inspect plugs every 5 years to prevent an electrolysis bonding between the plugs and the heads. Noting many plug manufacturers' now say the plugs composition prevent this....but I am old school. Modern hi tech metal plugs will go 100K miles. Owners manual is says 120K miles...wow. Guess it all depends on your budget if no drivability issues. Myself, as I am crazy, I'd change at a 70K inspection or 5 yrs. Labor is easy and plugs can cost less than $10 a piece. Noting to take patience/ care with the plug wires, to avoid damage to the wires. The inspection is the wear (shape: retaining the sharp edges and looking for pitting) from spark/ electricity on the plugs electrodes and of course gap....reading the plugs porcelain in a Prius I'd think is unnecessary....just replace the plugs as you labored into the project. I am also a fan of using torque wrenches, die-electric grease and anti seize compound. Again FWIW.
[QUOTE="Skibob, post: 2909158, member: 168247How many miles did you get?[/QUOTE] I only have 112k original miles [2008 Prius]...I'm going to wait until 150k to change the plugs.
I bought my 12 year old Prius at ~182,000 miles and some of the plugs really did not want to come out, it was a struggle to remove them safely and required a lot of helper juice (cant remember what we used, some kind of penetrating oil maybe). Also the one on the end at the drivers side had rust in the top of the hole... IIRC priuschat had some threads about this being a known defect with the water diversion rubber between the hood and window, which was later fixed.... but it seems like some Priuses might be out there still drippin'
