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USArmyCombatMedic · 10-11-2013, 03:03 PM

Alright, Just got home and threw in a new Engine Coolant Temp Sensor. The truck starts and idles for about 2 to 3 min before dying now. It runs a bit rough (pretty close to normal) but I have a feeling that has something to do with the timing. I had my brother unhook the battery overnight so as to reset the ECM.

As for the MAP sensor. The article I read says to hook a multimeter up to the negative batter cable and middle wire of the MAP. It then says to turn the battery on and it will read 4.7 or there about (mine reads 4.6 which is pretty close). As you blow into the MAP sensor, the voltage is suppose to go down to about 0 (my MAP sensor voltage goes up to above 5). A bad MAP sensor is suppose to stay at 4.7 or 0 volts. Is this a bad sensor or is this some electrical problem? It seems that we could be onto something here...

Im sure this might help in some way or another but I forgot to tell you guys that the truck takes forever to start cold or warm. Im talking like 7 to 8 seconds of cranking. If I hold the pedal at half throttle or pump the gas pedal to half throttle it helps but still takes another 3 to 4 seconds of cranking. Fuel, Ignition, or electrical?

10-11-2013, 03:03 PM	#15
USArmyCombatMedic Registered User Join Date: Oct 2013 Location: Rushford, MN Posts: 23	Re: Starts Fine and Stalls Alright, Just got home and threw in a new Engine Coolant Temp Sensor. The truck starts and idles for about 2 to 3 min before dying now. It runs a bit rough (pretty close to normal) but I have a feeling that has something to do with the timing. I had my brother unhook the battery overnight so as to reset the ECM. As for the MAP sensor. The article I read says to hook a multimeter up to the negative batter cable and middle wire of the MAP. It then says to turn the battery on and it will read 4.7 or there about (mine reads 4.6 which is pretty close). As you blow into the MAP sensor, the voltage is suppose to go down to about 0 (my MAP sensor voltage goes up to above 5). A bad MAP sensor is suppose to stay at 4.7 or 0 volts. Is this a bad sensor or is this some electrical problem? It seems that we could be onto something here... Im sure this might help in some way or another but I forgot to tell you guys that the truck takes forever to start cold or warm. Im talking like 7 to 8 seconds of cranking. If I hold the pedal at half throttle or pump the gas pedal to half throttle it helps but still takes another 3 to 4 seconds of cranking. Fuel, Ignition, or electrical?