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1992 wont shift out of first

Michaeljp86

EVIL GENIUS
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I just bought another truck today, the same truck in my sig but a chevy. It has reverse but wont shift out of first gear. The transmission is only a few months old, it was bought off ebay from that guy in florida who sells rebuilt transmissions.

I checked for codes and it has 81 and 85. Anyone know what the problem could be?

DTC 81 - Transmission 2-3 Shift Solenoid Circuit

DTC 85 - Transmission Gear
 
clear codes,try again,if codes reset (back to limp mode)check the trans mission plugin for corroded pins.
check 2-3 sol for OHMs,should be over 20 or better.Middle left 2 pins to top left pin in the connector lets you check both 1-2 and 2-3 solenoids.
check also both VS sensors for OHMs,should be within 10 OHMs of each other over 1000 OHM.
Bad VSS was culprit on my truck with same symptoms(code 85)
 
clear codes,try again,if codes reset (back to limp mode)check the trans mission plugin for corroded pins.
check 2-3 sol for OHMs,should be over 20 or better.Middle left 2 pins to top left pin in the connector lets you check both 1-2 and 2-3 solenoids.
check also both VS sensors for OHMs,should be within 10 OHMs of each other over 1000 OHM.
Bad VSS was culprit on my truck with same symptoms(code 85)

Is the truck in limp mode? I thought limp mode was 2nd gear only. Thsi only has first gear. Ill check the solenoids and sensor. The lat guy who had it said there is a big glob in the harness where the sliced on a new connector.
 
Most trannys are updated with the newer style connecter when rebuilt-replaced. The new connector comes with a pigtail on it to splice to harness. The engine rpm/ oil pump drive sensor is tied to trans function. A scan tool makes checking output of the sensors very easy and fast.
 
Most trannys are updated with the newer style connecter when rebuilt-replaced. The new connector comes with a pigtail on it to splice to harness. The engine rpm/ oil pump drive sensor is tied to trans function. A scan tool makes checking output of the sensors very easy and fast.

I need to get a scan tool, whats a good one to get? Most of them are all OBD2 and everything I have is OBD1.
 
I pulled the battery cables off to clear the codes, now it has 2nd gear only and codes 81 85 and 86.
 
DTC 81 - Transmission 2-3 Shift Solenoid Circuit

DTC 85 - Transmission Gear

DTC 86 - Transmission Gear Ratio Error

What would cause 86?
 
DTC 81 - Transmission 2-3 Shift Solenoid Circuit

DTC 85 - Transmission Gear

DTC 86 - Transmission Gear Ratio Error

What would cause 86?
IMO,you got a bad 2-3 solenoid or the conn/wiring is faulty.

85 and 86 are transmission error codes
85 is ,slipping component,could be set by the bad 2-3 sol.
86 could be caused by an bad VSS.

I would toroughly check the transm connector and wiring for continuity.
and as i said before,OHM the shift solenoids and both VS sensors,replace all if not sure,they are cheap.
 
The code 86 is triggered by a mis-match on the input vss and output vss for what gear it thinks it's in. My '93 had similar issues a couple of years ago. I replaced both the 1-2 and 3-4 shift solinoids and the problem went away. The output vss is what drives the speedo, input vss is only for the computer. On the '92-93 the computer only runs the 4L80E tranny.
Don
 
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