My 99RX (100K) engine still knocks after changing spark plugs, use premium gas (Chevron-techron), even with additive (Chevron-techron cleaner), MAF is clean.
I would really appreciate any ideas on what's going on...love the truck, just minor set-backs...

Mel

 

Knocks? Or ticks?

The RX engine (3.0, 3.3 v6's) are LOUD!!! The injectors cause the engine to make a ticking noise and the exhaust note during idle is a low rumble. Thats the way they were built

 

Yes, I hear what I guess are the injectors ticking away - it is pretty loud at times - wish there were some more sound proofing. MIght be me but I hear it more I think on the '03 than the '99, who knows. I do not hear much of an exhaust rumble or I would be really annoyed. IMO the '03 just needed more firewall sound proofing and a much better windshield for the wind noise.
I'll have to redrive a 330 and compare.

 

Nope, it's only during acceleration as if I did not put a good grade of gas in the vehicle. Idle is perfect and quite quiet as well.
Hey Derek, thanks again for you input and I'll get the timing checked on it.

Any other ideas from anybody would be appreciated...

 

mel,

The RX engine is built to not allow knock by using two sensors to listen for knock and retard timing to stay out of the knock range of spark timing.

I would say if you have knock on acceleration that one or both sensors are bad (one on each bank of the V6) or the ECM for the engine that they go to has a problem, or broken wire, etc. I would expect a Check Engine light if a sensor was bad, but you never know.

This is a difficult one to trouble shoot without replacing parts or the right diagnostic equipment. I would take it to a dealer (toyoda or lexus)