1990 Toyota Overdrive problem

[pewitt]

we have a 1990 Toyota 4 runner that kicks in and out of overdrive at highway speeds. Been to 3 shops with no resolution. Trying to do the E-17 repair ...any other ideas??? Thanks

[Brian R.]

Check your thermostat and ECT sensor.

[pewitt]

Originally Posted by Brian R.

Check your thermostat and ECT sensor.

Thank you very much for the help. I am delighted to find out there people out there with some answers. This problem has been intermitant and often requires an hour or more before it happens. The temperature guage is registering about where it ought to be and the problem occurs WELL AFTER we have reached normal operating temperature. After discussing it with service managers at two Toyota dealerships and giving $300 to a "Toyota specialist" shop in Phoenix Arizona I got a copy of Toyota Technical Service Bulletin (TC92-002REVISED) from Wheeler Toyota in Grants Pass Ore. titled INTERMITTANT ENGAGEMENT OF OVERDRIVE (REVISED). No one could tell me how to identify the E-17 splice so I soldered all three splices in the wire loom. It did not drop out of overdrive on a round trip to Medford 50 miles each way. It has been intermittant, and I am a sceptic, but I am cautiously optimistic that it is cured. I will pursue your advice as followup. Thanks much!!!! E. Bruce Pewitt.

[Brian R.]

Good job. Too bad it cost you.