Toyota Repair: choke running erratically, oxygen sensors, intake leak

Question
1993 toyota pickup, 2 wheel drive, 22RE engine, fuel injection (no carburetor). When first starting - cold engine - I think the automatic choke is going crazy. The engine revs very high and slows way down, all in about 2 seconds. This goes on until the engine is warm or perhaps until the choke would normaly kick off. Tapping the gas pedal doesnt disengage the choke. My check engine light has been on for a few months. I had this checked when first it came on and was told it was the oxygen sensor in the exhaust system and that it wouldnt hurt the running. At $150 for a sensor I havent replaced it yet. My question is what to do about the erratic choke idle and how important is it to get the oxygen sensors replaced? Thankyou for your help.
Quay Marshall

Answer
First of all there is no such thing as a choke on an EFI engine, the fast idle is controlled by the computer based on input signals from various sensors on the engine. It would also be helpful if I could have the trouble code number that is causing the check engine light to be on.
I can't make a diagnosis based on what someone else told you.
The O2 sensor is probably not the problem it may only be reacting to whatever other problem the engine is having and the computer sees this and turns the check engine light on.
Check for any kind of an intake leak, check the large hoses from the air filter over to the throttle body and any other hoses on the intake system that may be disconnected, this is the most common cause for erratic idle conditions.