I have a 2007 honda pilot with 163000 miles. There is bubbling/flaking/rust at the top of the rear wheel arch on one wheel. I noticed it a few months back and it is getting worse now that the rust is coming to the surface. Aside from the rust, the car is fine and I would like to keep it as long as possible given the high price of a new vehicle. What could/should I do at this point to stop the rust?
Rust that's bubbling up through the paint generally means it started underneath the paint somewhere and spread from underneath the panel's paint. I'm guessing a rock or something chipped the bottom edge of the panel years ago and got through to the metal, then water and oxygen worked their cruel magic. The rust extends somewhat beyond the bubbled area. If you press on the bubbled paint the body panel crumbles away, then you can't remove the rust in that area and resurface the metal -it's gone. If it doesn't, there may still be useable metal under it. You would want to sand off the rust and old paint on both sides, going about an inch or so beyond the obviously damaged area to make sure the rust is gone. Then you need to clean the area, mask it off from the rest of the panel, prime, paint, then clear coat it.
It may look funky if it's a larger spot because it doesn't match the rest of the car, fade-wise. But that'll at least stop the rust. I did this to a 23 year old BMW whose driver's door bottom was rusting. It stopped the rust in its tracks, but you could see the clear coat was new. I didn't care, I just wanted it to stop rusting.
