Loss of Giddyup... Possibly Tranny? Torque Converter?
 

Hi all,
Just the other day i started noticing some issues with power in my 2000 Blazer 4x4 with 92,000 on the clock. I was driving down the interstate with 2 other light passengers with me. I live in WV so yes the interstates are quite hilly. When climbing hills it would have a problem doing 65mph. It would kick down to first and the tach would jump to 5,000 RPMs. But the tranny always shifted flawlesly? I run the interstates all the time with passengers and if i ever push it down it will do 80, 90 whatever i need? It just seems like it could be slipping or just loosing power. Also when i backed off the throttle it didn't shift down as quick as normaly, maybe that was just because it couldn,t keep up? Any Ideas... I was thinking torque converter? tranny? possibly clogged cat (power loss)?
Thanks for the help.

What does the tranny fluid look and smell like? Try manually putting the tranny in whatever gear you want it to be in and "feel" for slippage.

Thanks for the reply bandidonenny,
The fluid is ruby red and didn't smell burnt at all, It smelled a little different ( hard to explain) but not burn't. The fluid along with the tranny filter were just changed like 5,000 miles ago. I i changed it so I know it was DEXRON. I took it for a drive, and 1st gear felt pretty strong, 2nd and 3rd just felt weaker, maybe not a slipping feeling but underpowered. Over drive I couldn't really tell because when i pushed it down it would just shift. BUT, I was running it harder than usual on my drive and i got a Service engine light! Goody Went to advance auto and used their OBDII scanner and this is what I got. 5 CODES

PO131
02 Sensor Circuit Low Voltage (Bank 1 Sensor1)

P0151
02 Sensor Circuit Low Voltage (Bank 2 Sensor1)

PO143
02 Sensor Circuit Low Voltage (Bank 1 Sensor3)

PO131
Same thing Just marked Pending

PO151
Same thing Just marked Pending

The alternator was replaced like 2 months ago because it had issues keeping the volts above 14v. The new one doesn't do it as bad but every once in a while I watch that needle dwindle right below the 14v mark.
Is it possible 3 o2 sensors wen't bad all at once?
Could this be related to my power loss issue?
As always thank you all for your help.

Those codes can definitely contribute to your condition. And no, it is not likely that all three of the sensors have gone bad all at once. The likely cuprit is a problem with the ground or voltage supply to the sensors.

The diagnostic sheets are posted in the Tech Article (DIY) section:
P0131 - HO2S Circuit Low Voltage Bank 1 Sensor 1
P0143 - HO2S Circuit Low Voltage Bank 1 Sensor 3
P0151 - HO2S Circuit Low Voltage Bank 2 Sensor 1

Thanks so much Kyle. I'm sure it's going to be a huge PITA trying to track this down but at least now I know where to start.
Thanks again!

Once you get through the diagnostic sheets, be sure to post up if you have any questions.