hi mud, I could use some advice. 07 LX470, 190k. I've had the truck for 3 years and 20k miles. No major issues until a few weeks ago.
Was driving over a mountain pass and noticed that when I accelerated, there was a high pitched whistle from engine bay. Letting off the gas slightly caused the whistle to stop. On the downhill side of the pass, the engine started to idle rough and then I lost all power. Slowed it down and got safely to side of road. Checked fluids and temps, all gauges looked normal. Started it up, no CEL and kept driving. The next day (120 miles later) CEL + VSC TRAC lights came on. OBD says its a P0420, driver side bank.
I talked to my local Toyota mechanic about O2 sensors & cats and he suggested testing for exhaust leaks. Local muffler specialist checked it out and said no noticeable leaks, although I hear a "tick" periodically, even after warmed up. He suggested replacing the cat and that driving it was OK, even with the 420 code.
I drove into the mountains again on Thursday and on another mountain pass (this time going uphill) engine stalled and I coasted to a stop, this time, no shoulder at all. Outside temps high 80s, AC on. It took about 40 minutes to get it started: electric and starter were going, but engine would n't catch, kind of like when you run out of gas. could be a fuel system issue? I got it started and turned around, as I didn't want to have bigger issues way out in the boonies.
I've read a bunch of posts about these various issues and have a list of preventative maintenance to do since I am unsure about the history:
- spark plugs (perhaps backing out?)
- throttle body cleaning (if super dirty, could it run too lean/rich?)
- MAF sensor cleaning (couldn't hurt?)
Can a bad/clogged cat cause loss of power? Other suggestions?
Thanks in advance for pointing me in a direction. Also, I have an OBD reader, but not tech stream.
JD
Was driving over a mountain pass and noticed that when I accelerated, there was a high pitched whistle from engine bay. Letting off the gas slightly caused the whistle to stop. On the downhill side of the pass, the engine started to idle rough and then I lost all power. Slowed it down and got safely to side of road. Checked fluids and temps, all gauges looked normal. Started it up, no CEL and kept driving. The next day (120 miles later) CEL + VSC TRAC lights came on. OBD says its a P0420, driver side bank.
I talked to my local Toyota mechanic about O2 sensors & cats and he suggested testing for exhaust leaks. Local muffler specialist checked it out and said no noticeable leaks, although I hear a "tick" periodically, even after warmed up. He suggested replacing the cat and that driving it was OK, even with the 420 code.
I drove into the mountains again on Thursday and on another mountain pass (this time going uphill) engine stalled and I coasted to a stop, this time, no shoulder at all. Outside temps high 80s, AC on. It took about 40 minutes to get it started: electric and starter were going, but engine would n't catch, kind of like when you run out of gas. could be a fuel system issue? I got it started and turned around, as I didn't want to have bigger issues way out in the boonies.
I've read a bunch of posts about these various issues and have a list of preventative maintenance to do since I am unsure about the history:
- spark plugs (perhaps backing out?)
- throttle body cleaning (if super dirty, could it run too lean/rich?)
- MAF sensor cleaning (couldn't hurt?)
Can a bad/clogged cat cause loss of power? Other suggestions?
Thanks in advance for pointing me in a direction. Also, I have an OBD reader, but not tech stream.
JD
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