Road trip sudden power loss :(

should be solid from Rockauto.

 

If it gives you reference, typically speaking, once the engine is warmed, my sensors are typically 3.2-3.3v for upstream, and 0.6-0.7 on downstream. Downstream fluctuates with load, less than 1v and typically a range of 0.5v from 0-80mph. Upstream stays pretty consistent. The two sensors aren't always in sync, but virtually never exceed 0.1v difference, regardless of position. I have some screencaps from my OBD tool's dashboards I can post if it helps.

Note: My 2006 is the VVTi version of our shared 2UZ-FE, so it may not be identical to your 2003 non-VVTi. At first start, the downstreams typically read 0v. They kick in and start ramping up after a mile or two of driving. My truck has ~80k original miles. At least 3 of 4 sensors are factory, I had to replace one a couple years back (downstream) and used genuine Denso.

 

wait so it's drinking fuel?

so it's gotta be running crazy rich.
Is one of your injectors stuck open?

 

if you could id appreciate it

 

my buddy suggested this but I haven't investigated anything yet

 

Sure thing.

I'm using the OBDLink MX+ bluetooth module, with their prepackaged software. I have a slew of gauges setup currently and keep switching it up. I've got one setup to monitor air/fuel, all four O2 sensors, transmission temps, and now the coolant temp (in my later dashboards).

I'll post some here, with a few comments before each pic. I really want/need to include a speed and RPM gauge in this dashboard. I'll probably do that in the near future, just so I've got a reference for these values, knowing voltage on the rears tends to climb with speed.

This is after starting, after driving a few blocks away from my house. No warmup period. Typically, downstream sensors are at 0v and upstream are in their usual voltage of 3.2-3.3v and note the coolant temp coursing thru the engine is at 105.8, it doesn't take long to crack into the 3-digit range.

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These next two are as I'm readhing operating temp on the interstate, doing 55-75mph

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Finally, this was me hopping off the interstate on the way home, driving in-town which I average 25-45mph in general. I can tell you this with pretty high confidence, because I was taking the oldest out on a hike south of ATL, and that required 5 minutes getting to the interstate, about 25 minutes of interstate driving, then another 15 minutes of mixed surface roads to get to the location, and the timestamps/GPS on the images (which I can see on my side before upload) confirm rough location on these. You can verify the time in the top-left corner also, from the phone itself to sort of get a gauge on the warmup period and general time.

Note with the lower RPM/lower speed, the downstream both backed off to ~0.5v overall. If I'm looking at the gauges between stop lights while running warm, the voltage varies by ~0.5v maximum, both are usually staying in sync. I can't remember ever seeing that downstream number exceed 0.8v and it typically doesn't drop below 0.2v once the engine has warmed up, I'm sitting at a stoplight, whatever.

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Couple more dashboards from today. I’m idling while I wait for the kid at practice so I got off my ass and setup the extras.

I’ve noticed my downstream passenger sensor, factory original, is lazy. It hasn’t been replaced yet. These were taken about 15 seconds apart.

 

So you cleaned the MAF but not the throttle body? If you haven’t I’d clean it up and make sure its not stuck and opens and closes normally.

 

i did end up cleaning the throttle body as part of the pre-trip maintainence

 

Also... have you tried a compression test? Bad compression will also cause the "loss of power"

 

low compression wouldn't cause intermittent power loss though only when warm would it? if it were low compression wouldn't it be similar power loss 100% of the time?