Hi: I can't believe I am the only one in the history of Toyota to have this problem. Please, if anyone else has had this happen, let me know how you fixed it. Thanks..sorry for the repost but I am desperate...
The timing on my 1998 V6 Tacoma is extremely retarded....so much so the mark does'nt even hit the timing tab. It does advance when rpm increased. It backfires on descents and has absolutely no power to climb a hill. There is no check engine light illuminated. There were no trouble codes with OBD2. I have replaced plugs, wires, fuel filter, and checked the coil overs with an ohm meter. Everything seems fine. It has 93k on it so I know it is due for a timing belt. It has been suggested that the belt may have jumped a tooth....but I didn't want to dive into that until I have tried other possibilites. If it jumped a tooth would it most likely advance or retard? Does anyone have any other suggestions or seen this before? Thank you very much for your input.

 

Given what you did already, it's time for you to pull the top timing cover and check that the belt hasn't jumped.
Pull the cover, line up the crank to TDC and then check the cams to make sure they both line up with their marks.