Have owned my car since new. 170k on the original spark plugs. Do I have to install plugs regardless of how good it runs? How about spark plug wires and coils? Thx
Your plugs are living on borrowed time. I had the plugs replaced on my Corolla at 110k and that was too long. In fact, you should be coming up on your third set.
At 170k and 22 years, they’re probably seized into the heads and aren’t coming out easily.
If it ain’t broke don’t fix it.
I’d consider the timeline of the vehicle. It’s pretty old now. Have you started planning for its replacement? If so, maybe move it along to a new owner and avoid getting into the deferred maintenance. ANY car has a value today.
Factory plugs in a Toyota are NGK or Denso. Both have trivalent coatings that prevent the plugs from seizing in the head. I just pulled a set of factory NGK plugs from a ten year old Dodge Avenger with 147,000 miles and they came right out without any issues.
I have a 2005. The Chilton manual recommends changing every 120,000 miles. I suspect same thing applies to 1999 variant. They are meant to be replaced at some point as preventive maintenance. I would recommend replacing it. It’s not hard to do either.
Unless it is a 6 cyl.
If this is a 4 cylinder replacing the plugs is easy, the Chiltons manual has instructions or look it up on line (1999 Toyota Camry Spark Plug Removal and Replacement - YouTube). Remove the plastic engine cover if it has one and remove the coil covers. Use compressed air to blow out any debris. Due to the age it would be worth spraying PB Blaster on each plug and let it sit for a while. Might stink when it burns off, but reduces risk of messing up the threads. I found the only place to get the proper Denso plugs was the dealer and the price was not out of line
Change em out. Especially if it’s a 4 cylinder. Cheap and easy way to avoid future problems. If it’s a 6 cylinder…the cheapness and easiness varies by make.