88/89 4runner shifting issue

[cwillis]

my 4 runner has the following transmission symptoms:

shifts into 1,2,3,4 fast! no matter my throttle posistion
will not downshift automatically

shifts manually perfectly
all shifts firm and healthy


how do i test the tps? fsm says test ecu ports, but they are under the radio, cant get probes in there muchless see what im doing.

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i pulled the rubber boot off the tps and tested voltage between top two wires. i have a .1v closed and about 1 volt wide open.

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checked with ohmeter the top two connectors with wire harness off the sensor.

open leads with throttle shut
1.4k ohms wide open.
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[cwillis]

today the transmission was the same as described before.
i drove to a shopping center, and when i came out and started the truck again the transmission was perfect. it shifted at the perfect times, downshifted perfectly.

so it seems like a loose connection. but where? tps is secure!

 

[drmorbius]

today the transmission was the same as described before.
i drove to a shopping center, and when i came out and started the truck again the transmission was perfect. it shifted at the perfect times, downshifted perfectly.

so it seems like a loose connection. but where? tps is secure!

Try following the leads from the tps down to the trans. Unplug the connector at the trans and spray the contacts both male and female with a contact cleaner. I would also do the same at the tps.

 

[cwillis]

thanks for that advice. i will see if i can fit down there andl\ clean those out.

by the way, 4 trips today. 3 have been perfect, one with the bad symptoms.