Loss of power at 75 mph

Can some one tell me what my problem could be. When I get to about 75 mph, I press down on the gas pedal and nothing happens. It all started about a year ago when my truck would jerk while accelerating every so often. Also, when my family went camping in the Ozarks, my truck would slow way down going up hills. I've never had this happen before when my truck has been weighted down with camping gear and a canoe on top. My truck is a 2001 dbl cab v6 4x4 TRD. I replaced my fuel/air sensor and my o2 sensor. Could this be a clogged catalytic convertor?

 

sounds like it whats the milage, and cels in the past associate with the CAT

 

157,000. Went to autozone w/ a po420 code. Told me it was a clogged cat, but another store said it was a bad o2 sensor. That's when I put new sensors in and the check engine light turned off and has stayed off.

 

My truck does this every now and then.

 

Could be the CAT. Might be worth dropping the exhaust forward of the CAT and go for a test drive.

Does it jerk and stumble, or just no power? If it stumbles and runs rough could also be a clogged fuel filter, weak pump, or bad plug wires.

 

It hasn't stumbled in a long time, just loss of power at high speed. I live in the middle of the Mississippi delta and havn't been able to test my truck on hills.

 

Not really the same truck, but I have a friend who drives an 03 2wd 2.4 Taco. It was running smooth, but wouldn't hardly go over 70MPH on flat ground. It ran like that for a couple of years, finally set a check engine light for the catalytic converter efficiency. It got a new CAT, and the power increased noticeably under load on the freeway. I think it had around 130-150K on it at the time the CAT was changed.

My parents had an Astro van (yuk!) that would run okay in town, then start jerking and losing power in the mountains on vacation. The first time it was the fuel pump. The second time with the same symptoms I changed the pump first. Again, ran fine in town, ran like crap in the mountains. Turned out to be the plug wires.

 

X2 on these, If there are plug wires and they are OE it may be time for a change.

It sound like a fuel issue to me with lower power when hauling at lower speeds. Either the filter or the fuel pressure.

I've never had a bad CAT so I would not know about that....

Good luck

 

Thanks for the responses, I'll try new wires and fuel filter since they're a cheap fix. Would y'all go with factory wires or after market. What brands work best.

 

If you can get factory Toyota wires at a reasonable price, I would go with those. I believe in factory parts as much as possible. I've tried all the aftermarket wires and the best I've found (don't pull apart when changing plugs) are the Belden wires at NAPA. They used to be lifetime warranty, not sure now.

 

sounds like the muffler bearing to me

 

Could be? After replacing the muffler bearing make sure you give the Power Band a good tightening as well.....