Lound but inconsistent engine noise: 02 Rav 4


My 2002 Toyota Rav 4 has been to the shop 2 times in the last 6 weeks for the same noise. The problem is that the noise only occurs after the car has been driven for more than and hour at highway speeds. The noise is a very loud knocking sound that seems to be coming from under the drivers side hood. It gets progressively worse on long road trips. The noise stops after long road trips so the mechanic has not been able to duplicate the problem or diagnose it properly. The 2 times that the noise has ocurred have been hot days in the desert so we have had the air conditioning on. We also passed over a mountain pass so the car was working hard. Any ideas? I need help as I don’t want to take it in to the shop again.


Try to make an apppointment with the shop to stop by at some specific time, then take a 2 hour drive just prior to the appointment, driving straight from there to the shop.

This sounds like a possible case of bearing knock. If so, unless you have a warranty I’d try a heavier weight oil. The solution involves tearing the bottom of the engine apart. In essence a bottom end rebuild.

Post back with how you make out.
Sincere best of luck.