My 94 dodge ram 1500, 5.2L, runs okay but began using lot of fuel. Had trouble codes 37, 32, and 51. Cleaned throttle body and checked for vaccum leaks or bad hoses. Code 32 gone away. Cleared code 51 which according to Haynes manual is not supposed to make the check engine light come on. Their is no code 37 in the Haynes manual for a gasoline engine on the 94 Ram. Their is for diesel engine. What is it, where is it at and how do I correct the problem. 51 I know is the O2 sensor. Truck runs great, shifts fine , but is still using more fuel than normal. Been reading about code 37 and transmissions, don't think my problem is there. Any help ?

http://www.bestvalueautoparts.com/Replacement_Parts/DODGE/PICKUP _RAM_1500/Air_Temperature_Sensor.html

Found bad coolant hose and water pump, changed oxygen sensor (only has one, upstream). All codes clear , except code 37. Transmission is going into overdrive. Check engine light not coming on but code 37 is still in system. Not going to worry about it. Truck has 211,763 miles. Going to drive it. Thanks for the help ??

...this goody is the only thing your ECM has to know how rich it's gonna make the fuel~

Code list 37 show as transmission (in diesel) however is PARK/NEUTRAL SAFETY SWITCH (in gas). My truck sometimes won't start in park or neutral, just have to shift back and forth till it starts. Hane's book says switch is in transmission. It maybe out of alignment or just bad.

Code 37 on a 94 5.2 rwd is the Transmission Control solenoid aka the Trans pressure solenoid. It is located inside of transmission pan. Drop the pan and you'll see a bracket with 2 small cylinders and a wire with another plug. That is it. Once you change it, hook your battery back up. Of you still get the code, there is probably an open circuit somewhere associated with this.