99 Marquis Transmission shifting problem
rhl9580
03-28-2010, 10:16 AM
Hello,
My Vehicle
1999 Mercury Grand Marquis LS
V8 4.6L - 114,000 Miles
My Story / Problem
When I bought the vehicle the dash gauges did not work and the transmission shifted hard all the time. Sometimes it would feel like a jack hammer when shifting like it was shifting gears up and down repeatedly very fast. It would do that until I give it more/less gas.
Stuff I done to try and fix it
Dash gauges where traced to fuse #13 being blown replaced the fuse only to have it pop again. Traced that problem to a short with the overdrive button on the gear shifter knob disconnected the overdrive wire and that stopped fuse #13 from blowing. All dash gauges work and overdrive is on I just have no way of turning overdrive off until I replace the overdrive button no biggie.
After reading the manual found out that fuse #13 also powers the automatic transmission but does not say exactly what it is on the transmission that its powering. So far reading in forums what other people have done I've had no luck.
Here is a list of what I've replaced so far.
Shift Control Solenoid
Torque Converter Clutch Solenoid
Speed Sensor
Throttle Position Sensor
Another sensor that I' am gonna replace but haven't yet.
Auto Trans Speed Sensor
Even after replacing these parts I still have the transmission problem anyone with suggestions please help Thanks.
My Vehicle
1999 Mercury Grand Marquis LS
V8 4.6L - 114,000 Miles
My Story / Problem
When I bought the vehicle the dash gauges did not work and the transmission shifted hard all the time. Sometimes it would feel like a jack hammer when shifting like it was shifting gears up and down repeatedly very fast. It would do that until I give it more/less gas.
Stuff I done to try and fix it
Dash gauges where traced to fuse #13 being blown replaced the fuse only to have it pop again. Traced that problem to a short with the overdrive button on the gear shifter knob disconnected the overdrive wire and that stopped fuse #13 from blowing. All dash gauges work and overdrive is on I just have no way of turning overdrive off until I replace the overdrive button no biggie.
After reading the manual found out that fuse #13 also powers the automatic transmission but does not say exactly what it is on the transmission that its powering. So far reading in forums what other people have done I've had no luck.
Here is a list of what I've replaced so far.
Shift Control Solenoid
Torque Converter Clutch Solenoid
Speed Sensor
Throttle Position Sensor
Another sensor that I' am gonna replace but haven't yet.
Auto Trans Speed Sensor
Even after replacing these parts I still have the transmission problem anyone with suggestions please help Thanks.
Blue)(Fusion
03-28-2010, 01:45 PM
Replace the Manual Lever Position Sensor (MLPS), also sometimes mistakenly referred to as the "neutral safety switch". It is on the driver side of the transmission body.
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