Wont Shift into Overdrive
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Wont Shift into Overdrive
I have a 95 SC300 Automatic with about 170,000 miles i bought this car about 8 months ago
The problem started about a week ago. i noticed that while going about 50-55 mph my rpms stay at about 3000rpm when usually they would be below 2000. so the first thing i did was press the overdrive button the shifter and nothing the Overdrive light doesnt come on in the dash when it used to and it still doesnt go into overdrive. all of the other gears go in fine. no slipping no hard shifts, it downshifts smoothly.
next step i did was change the Fluid and filter in the tranny and still nothing.
the tempurature outside usually is around 80-90 degrees, but we had a cold front for the past week and outside tempuratures are around 35-50 degrees. i noticed while driving i see the tempurature gauge stay below the middle where it usually is. could it be that the person that had the car before me took off the thermostat? ive yet to check but it seems like the thermostat is either stuck open or there is no thermostat at all from just looking at the temp gauge..
i read on other forums that if the operating tempurature on the car is too low, the ECU wont let the transmission shift into overdrive so it wont put a load on the motor while it being under the operating tempurature. i dont know if this is true.
has anybody ever had this issue with there SC300s?
Could it be that my Transmission is on its way out?
I also hear it could be my ECU is going bad. i just dont know what to do.
The problem started about a week ago. i noticed that while going about 50-55 mph my rpms stay at about 3000rpm when usually they would be below 2000. so the first thing i did was press the overdrive button the shifter and nothing the Overdrive light doesnt come on in the dash when it used to and it still doesnt go into overdrive. all of the other gears go in fine. no slipping no hard shifts, it downshifts smoothly.
next step i did was change the Fluid and filter in the tranny and still nothing.
the tempurature outside usually is around 80-90 degrees, but we had a cold front for the past week and outside tempuratures are around 35-50 degrees. i noticed while driving i see the tempurature gauge stay below the middle where it usually is. could it be that the person that had the car before me took off the thermostat? ive yet to check but it seems like the thermostat is either stuck open or there is no thermostat at all from just looking at the temp gauge..
i read on other forums that if the operating tempurature on the car is too low, the ECU wont let the transmission shift into overdrive so it wont put a load on the motor while it being under the operating tempurature. i dont know if this is true.
has anybody ever had this issue with there SC300s?
Could it be that my Transmission is on its way out?
I also hear it could be my ECU is going bad. i just dont know what to do.
#2
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could be a few things transmission shift point controled by three elements. Engine temp sensor located behind the water inlet from the rad. Also tps and ecu. it could also be a solenoid in the trans itself. The easiest thing to try is the ecu. If you can borrow a KNOWN working ecu it should solve ur problems if not give the other things a check
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could be a few things transmission shift point controled by three elements. Engine temp sensor located behind the water inlet from the rad. Also tps and ecu. it could also be a solenoid in the trans itself. The easiest thing to try is the ecu. If you can borrow a KNOWN working ecu it should solve ur problems if not give the other things a check
Is there Any SC300 owners in the West Palm Beach FL area that can let me use your ECU for a couple minutes i would greatly appreciate it.
#7
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thanks for your help. i have been trying to find somebody locally with an ECU but i havent had any luck...i have a friend that has a 97 sc300 but i believe his is OBD II mine is OBD I and he said that his computer wont work on my car. is this true??
Is there Any SC300 owners in the West Palm Beach FL area that can let me use your ECU for a couple minutes i would greatly appreciate it.
Is there Any SC300 owners in the West Palm Beach FL area that can let me use your ECU for a couple minutes i would greatly appreciate it.
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#8
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thanks man if i cant find anybody localy, i will definatly be sending u a PM.
pembroke pines is that exit Hollywood? i think thats like about an hour away.
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same peoblem
I have a 1995 sc300 that will not shift into overdrive. The only other thing is the track light comes on and stays on. Could that be the ecu or the senser on the trans axle.
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