--- In toyota-campers@y..., "Ed Flaherty" <ed@m...> wrote:
Thanks to all who gave advice about my overdrive problem.
Jack Redman's fix worked. This involved removing the overdrive
solenoid and taking one of the O-ring seals out (the inner one which
is the smaller of the two). In inspecting the solenoid I came to
the
realization that taking this seal out has the effect of bypassing
the
solenoid valve and letting fluid flow through it which causes the
transmission to go into the overdrive mode. Of course when you do
this the solenoid no longer is able to seal off the port so now the
valve can't turn the overdrive mode off. OK with me.
While I was under the machine I tried to trace the wiring back up to
the engine and found a connector that had come loose, one of those
that looks like a small plastic barrel and has an O-ring seal on one
side. I think this is connected to the overdrive solenoid but am
not
sure because its kinda hard to see where things go down in back of
the engine there. I connected it back up. I suppose the thing to
do
now is to get back under and put that seal back in so I can check
it.
While I was troubleshooting I had a chance to test the temperature
sensor that sends the temp readings to the computer. It's located
(on my 86 22RE) between the EFI cover and the valve cover as you
look
at the engine from the front, very easy to get at. There are two
small sending units here with square connectors of the type that
have
a thin wire that snaps
in place around the connector to lock it in place. The one on the
right is the temp sensor. Using a pocket knife with a small tip you
can get under the locking wire and pull it away from the connector,
you don't have to pull it all the way off, just enough to hold it
away from the indentations so the connector will pull off. Inside
are two blade contacts. Using a multimeter set to read resistance,
hold a probe on each contact and check the reading. You should use
the R x 10 scale on the meter. The reading should be high when the
engine is cold, over 2000 ohms, then warm up the engine (put the
connector back on when you do this since the computer uses this
reading to adjust the fuel mixture). Shut off and read again after
a
little warmup. The reading will gradually come down as the engine
warms up. I found that a reading of 600 ohms corresponds to about
180 degrees engine temp.
Thanks again guys, I probably saved a couple hundred bucks in
mechanics bills and another $100 in gas on the trip to FL.
-ed
Ed.
Good info for those of us running the auto trans'.
Good stuff also on the temp sensors.
Your post goes into my Toyota file. Thanks.
Jack A2
Jack A2
