2001 Toyota 4Runner: Clicking Engine

It has 160,000 miles, has received all scheduled maintenance from same Toyota mechanics since new. Started it this morning and the engine started making a fairly loud clicking noise coming from top front of engine just behind radiator. Also idles a bit erratically. This engine has always been very quiet. Any thoughts? Is is safe to drive 40 miles to my mechanic?

Beerman, Let’s Get This Out Of The Way. Define “All Scheduled Maintenance”. How Often Has The Oil Been Changed, Without Fail, Throughout The Entire 160,000 Miles ?


When in doubt, tow it out (there).

A tow charge is much cheaper than an engine replacement if the engine blows up on the way.

I have followed the owners manual maintenance schedule exactly(to the letter). I bought this vehicle new in November 2000. After an initial oil change at 1,000 miles, it has gone in for service(as stated in the owner’s manual) at the same independent certified Toyota shop at 5,000 miles and every 5,000 miles thereafter. This shop has specialized in Toyota, Honda and other Asian vehicles for over 20 years. I am very insistent that the oil is changed and all other required service is performed every 5,000 miles.
Could this be a timing belt or tensioner noise? Or something more serious?
(My other vehicle is a 1988 Toyota truck: 290,000 miles also serviced every 5k miles at the same shop. Still going strong). Thanks for any help.

I’m having it towed to the shop tomorrow morning. Thanks for the suggestions. I’ll update this discussion when they let me know what’s going on. Hopefully nothing too bad.

Well, the 4Runner is just fine. They believe something may have got sucked in the air intake which caused the clicking sound. I will start a new discussion with their hypothesis: mouse nest material or the mouse itself was sucked in the intake!