95 4runner
 

Hey gang. I'm a new member to this site, but i've visited here ever since i've been having trouble with the rig.(I'm also a first time toyota owner)I've been very happy with it so far,till now.Since it's the first one i've owned,it's probably an easy fix(so I thought)About 2 months ago, i started having a problem with the 95.When I came to a stop, it would idle rough, and as I accelerated, it had no power and would start to buck at 60 mph. The cel came on with a 25 code.I had cleared the code, and then it came on a few days later with a 25 and 26.You could smell unburned: gas at the exhaust.I found this site and started reading the threads.Lots of great reading. I then started to replace parts. Cap,rotor,fuel filter, air filter,plugs ,wiresand recently the MAF sensor with a used one.( NEW...$1400...NOT CHEAP).Even after all this,the cel still flashed a 25.I'm pretty much at wits end.Hopefully you guys can help me try to figure out this very frustrating problem which some of you probably dealt with at some point.:horse:

How is your timing?

In 95 did they fix the head gasket problem on the 3.0?

burnt valve how many miles are on it?

i agree on the burnt valve.have you dome a compression ck?that would likely be the next step

I brought to the toyota dealership the other day, and the mechanic told me I would probably have to change the O2 sensor because I was driving it while it was running rough and it could have plugged it up. He said it might clear itself out. I'll see how it goes for a couple days . If not , I'll change the O2 sensor.

My vote goes to check the compression before you throw any more money at parts . The symptoms you described sound like my 95 Runner when the exh valve was burnt .
The head gasket problems might have been fixed by 95 but the exhaust manifold design will still burn the valves.
Good luck

Good advise. I'll check the compression on the weekend......if it's not too cold.(-42 c )........oh to be in Mexico!!!!

This might help

http://personal.utulsa.edu/~nathan-b...85diagnosi.pdf