popejoy

2009 GX470 - 145K miles. Anyone has this kind of issue? I went to a couple of mechanics, one said after working on distributor and adjusting timing, it need a machine shop. The other mechanic says, it's too rich. Anyone had this kind of issue? Please advise, I hate to take it to Lexus and get charge $$$$$.

IanB2

This is a coil on plug engine, there is no distributor..., ignition timing is controlled via the ecu, not externally adjustable. I'd have some questions about that 1st mechanic's invoice.

Is the engine throwing codes? How did the 2nd mechanic determine it was running too rich?

Can you describe the pinging noise and when it's happening exactly? All the time, just at idle, just when in gear, just when accelerating, etc? It could be detonation, what grade fuel are you running in it, 87, 91?

popejoy

Thank you. I will pull 2nd invoice and see how he came with that "too rich" diagnosis. Pinging sound like a valve tapping and continues, once you start the motor its on and gets faster as you gas it up. Im running on 91 octane.

chiph9

Yeah, that 1st mechanic was BS-ing you. Coil-on-plug ignition means no distributor, no points to adjust.

Something that does happen on the 2UZ motor however, is a cracked exhaust manifold. You should be able to listen for it with the hood up and the sound/beauty covers removed. If it's bad enough, you'll see soot around the crack. It will change with engine speed.

Chip H.

IanB2

If the "ping" could be an exhaust leak tick, then the manifolds are a good place to start looking. The sound would increase with engine revs.

popejoy

Thanks Chip, checked it and has no crack.

popejoy

Thank you IanB2. That would be my next to do. Appreciate all your help.