Ok i bought a 93 toyota xtacab. a week ago. i noticed right away a oil leak. but i still have to put a new pcv valve. my truck has lots of power when its cold. but after it warms up i am having to over rev the gears to get up to speed. feels kinda jerky when driving like a shutter. kinda lunges me forward and back. bought a new o2 sensor. have not put it in yet. will have to angle grind the nuts off. rounded. maybe the prev owner changed at some point? but looks like factory. the owner told me he has 80k on new motor. but that means like three to four years ago. so thats this week end. had a macanic look at it he said that it may have a dead valve but not sure yet still have to do a compression check. but maybe im asking for advice. but im proud to own such a nice truck. want it to be running great. the o2 thats on it says toyota on the rim not sure if oem part. or after.

 

oh btw the check engine light threw codes 14 and 25

 

I would check compression when cold, then again when it's fully warmed up. It's possible the valves are tight, and you're losing compression once it's warmed up.

Also, and maybe a more likely possibility, is the EGR system. To look up the codes, go here, although it's not always conclusive, sometimes it indicates problems actually caused by something else. http://www.off-road.com/toyota/tech/codes/index.html

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