I'm looking to buy factory direct parts to replace. Does anyone have a pics for the following parts on a 1995 GS300? O2 sensors (both) Valve Gasket Factory Direct Spark Plugs

i had a similar problem last summer my engine was revving very high then would shut off as to protect itself or air problem, but i found that i had a bad valve cover gasket after replacing it the problem corrected itself. the high revving was caused by too much air being drawn into the manifold with bad gasket
easy fix. just remember to tighten new gasket every other bolt opposite sides as you tighten not all at one end first
good luck

Have you checked/replaced the O2 sensor(s). They produce the data that your computer reads. Bad/clogged O2 sensors will trick the ECU into running lean/rich.

My first question would be, what was the original trouble code that directed the mechanic to replace the sensors ? You seldom need more than one O2 sensor at a time. Its possible the exhaust manifold is leaking and that might cause a problem that would turn on the warning light. Or it could be something else.
A valve cover gasket will leak oil if it fails. No check engine light.

O2 Sensors with over 100,000 miles on them

Dirty MAF Sensor

Old Spark Plugs

Ignition Problems

Blocked gas filter or blocked exhaust converter

Exhaust system leaks before converter

TPS Sensor

you will need a 21 or 22mm wrench. follow te exhaust from the engine, you are looking for a sensor that is screwed into the exhaust pipe just past the cat converter. unplug the sensor from the harness thn unscrew the sensor from the pipe. reverse to install.

Go to Advance Auto Parts and buy a can of "SeaFoam" $8...add to your fuel tank as directed and drive for at least 100 miles...If this doesn't work, you need to replace all of the O2 sensors in the exhaust system.
Good Luck

its very easy maybe it will take you thirty minutes if u want buy some cheap rubber gloves

this pic with be the fix ya

You need to get a diagnostic check done. Could be a O2 sensor or anything else that would cause your check engine light to come on.

what kind of car? irregardless, you can pick up a detailed chiltons or haynes repair manual for your model at a local auto parts store.