mrboyertown

I have a 94 Toyota SR5 V6 Automatic Pickup with 200,000mi. All together the truck runs good....no major problems. The only minor problem is that when the truck idles, or is even revved at a constant rpm with no load, it has a small lope to the engine.(The best way to describe it is that the truck vibrates with a little shimmy, nothing major, but I know the engine should be running a little smoother) Ive been getting a check engine light with the codes 2-5 and 2-6. In my manual it tells me that 2-5 code means the truck is running rich and the 2-6 code means the truck is running lean? I have already replaced the 02 sensor which wasn't cheap along with the spark plugs/wires/cap/rotor/ and before I go any further I was wondering if anybody else had a problem like this? The manual says it could be injectors, fuel pressur, ingnition sys., coolant temp sens., air flow meter and so on. I dont think its a mechanical problem because I get both codes that sometimes the truck runs rich and sometimes it runs lean. The truck runs perfect except for the shimmy, and the fuel mileage isn't the best. You cant even really notice the lope in the engine while driving, only when the motor isn't under a load. Im thinking my next move will be to replace the coolant temp sensor. Any Ideas?