Here is my case:
RAM 1500 , 1994, 4x2, 5.2 L
In idle, when is warm or hot, it begins like a hissing and later, engine turning off.
I replaced the IAC valve.Same thing. Replaced wires for sparks and distributor. Checked Throtttle Position Sensor. Looks OK.Checked Engine Coolant temperature sensor. Looks fine. Checked MAP sensor : Wrong values. Voltage is good in lows RPM, butdoesn´t increase as increases of RPM.

error codes: #21 O2 sensor
#73 Transmision temp sensor

 

hmmm...sounds a little complicated. Let me just remind you that just b/c you have error codes for on O2 sensor and a transmission temp sensor that this are at fault. I would suggest checking for a vacuum leak. If you have one, you would hear a hissing sound and it would also cause your truck to think it needs more fuel which could cause your O2 sensor to read an incorrect voltage. Make sure all vaccum lines are tight. Also, check air intake system for clog. I'm not sure of any incident that would cause both the O2 and transmission sensor to read wrong voltage.

 

First of all, thank you very much for your answer.
This car it´s make me crazy. I already paid almost $500 for repaired, and later, I had to go to the repair center during an entire month, and my truck has the same problem. I don´t want to go there any more. I´m trying to fix it by myself but still I can´t located the problem.
I inspected almost all vacuum lines looking for leaks, but I didn´t see it. Is there any way, or tool to check the leaks?
I checked the EGR valve and was clogged. I think I fixed, but still I have the same problem.

 

Can the MAP sensor make this fault??? What about the EGR valve control? Because I opened this and it was clogged. I think I fixed but I didn´t check the EGR valve attached to the engine.
I found 3 hoses damaged. I replaced and will test now. I only read now 1 error code : 37, but I´m looking for this error code in Haynes manual and it isn´t there. Somebody knows what this error meaning?

 

http://dodgeram.org/tech/gas/Trouble/pcm_fault_code.htm


Click on that link above. That might help you with your code.

 

Thank you very much !!!

 

I know everybody here is very busy and nobody has time for this problem, but still I´m fighting with my RAM. Ok, I noticed, that my truck is fine at idle now, while is cool, or it looks like if you drive slowly, and don´t press the accelerator so much, everything is fine, but if temperature becomes not high, only normal, idle becomes rought, and if I press the acelerator all time and increases the RPM, the problem is critical, until engine stop. i noticed too, that when I drive my caruntil itis warm, check engine light turn on and begins to fail.Now, I think maybe is a fuel problem. Somebody knows something about this ?

 

Finally I found the problem in my truck. Today I was tested all day and everything is VERY GOOD. Thank you very much.