95 Wrangler feels like it's "running out of gas"

[Capi502]

My 95 Wrangler (2.5/4 cyl) with 85,000 miles recently starting "losing power" at highway speeds. My mechanic correctly described it to me as "running out of gas". So far, this has happened at least three times. Twice, the "Check Engine" light came on, and I retrieved codes "51" and "52" from the memory. "51" is the 02 sensor, lean condition. "52" is "additive adaptive memory at lean limit". Based on this info, the mechanic changed my O2 sensor. A day later, the same problem happened. If I pull over, shut down the engine and restart, the problem disappears, and I'm able to get to where I was going with little to no trouble. The engine also seems to be idling rough when cold. Based on others' recommendations, I've cleaned the throttle control. I probably won't know if that will make a difference for a few days. The problem is sporadic and doesn't appear to be based upon length of trip or time -- just happens! I'm reluctant to take it back to the mechanic because they'll just start throwing parts at it -- if I'm going to throw parts at it, I'd rather buy the parts myself and replace them then pay the mechanic the labor. I've had this Wrangler since '95 -- it seems the only major problems I've had (this is the third) are those that take forever to figure out! Which is probably why I love it and won't let it go! Any help appreciated!!! THANKS!

[Buzzag]

Try a new fuel filter.

[Shiner]

Your Jeep's symptoms sound like my own 95 Wrangler 2.5L. It happens for me when the catalytic converter wears out and clogs the exhaust flow intermittently. I'm also told a bad 02 sensor can contribute to the degradation of the catalytic converter. I've replaced the converter a couple of times now at 181,000 and counting.

[jennifer206]

I Would Confidently Say The Problem Is The Fuel Pump/fuel Sending Unit. Take This Info For What It's Worth. I Have Seen Numerous Problems With Jeep Fuel Systems That Can Be Intermittent And Uncharateristic Of A Fuel System (they Seem To Be Unlike Other Vehicle Manufacturers' Fuel Systems That Either Function Properly, Or Fail) . Aftermarket Fuel Pumps/sending Units Can Also Be Problematic. If You Are Going To Get To The Root Of The Problem And Fix It Right, Go With Factory Parts. I Saw This Lesson Learned The Hard Way Many Times.