I replaced the head gasket on a 1994 22re Toyota pick up. When I finished I found a O ring on the floor. I am not absolutely sure that it came from my repair as the truck is used and it could have fallen from an earlier repair from a previous owner and fell out when I moved something. The O ring is about the size of a penny , any ideas where this O ring may have come from. I did not take off the timing chain cover water pump or anything in that area.

 

does it look like it has already been used or is it new? Possibly dropped it out of your gasket kit? Only o-rings that come to mind is distributor or fuel injector. I guess the fastest way to find out is to fire it up and check for leaks, since it's already back together.

 

It looked flat like it may have been used , it could have come from the distributor, I'll pull it out and check.As for firing it up I have already and it ran like crap. I tried to set timing and when I shorted the "T" it did not change the rpm's at all. Did some research on this great site and found that my TPS was more than likely bad. I checked it with a meter and could not get a reading. So now I have removed the throttle body to get the TPS off and I'm waiting on a TPS I ordered on E bay. I'm going to replace the screws on the TPS with allen head screws when I put it back.