My 92 4runner just started going nuts the other day while I walked into the store. I came out that the rpms dropped to about 800 or so. When I tried to leave I couldn't get it to go above 1500 rpms. After shutting it off and turning it back on it fixes itself for like 10 mins the while I was driving it happened again. My friend is some sort of a mechanic and said it could be firing order is messed up or something to do with the distributor or a vacuum line. If someone could help me out that would be great. Thank you