Toyota Repair: Fuel sensors, coolant temp, water coolant

Question
girl friends 93 Toyo Camry (2200) started over rev (max R's)all by itself.  No sticking linkage or vacume leaks, replaced the TPS the R's came back down.  Now idles about right R's but surges bad and will not take any foot feed, boges down.  I had it towed, put trany  in D at idle/surge and it rev'd up again, in N goes back to surge idleing ? help

Answer
Check the coolant level in the radiator, if it takes a lot of water/coolant to fill it up there is a leak so check for that, the engine surging up and down is caused by the coolant temp sensor, if there are air pockets the sensor will cycle the fuel injectors on and off causing this condition.