502 MPI VST Check
09-10-2004 | 01:04 AM
#11
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From: N.E.
Re: 502 MPI VST Check
Originally Posted by RonS
You may want to check that you are getting proper voltage to the temp sender, you said you had the motor apart so check all your pin connectors and make sure that there are no wires pulled out. If the temp sender is not working correctly the ecm may be putting the motor in the cold start enrich mode causing the excessively rich condition
will that show on the computer analyser as a code fault??
seems like something stupid like that is the problem!!
Is the temp sensor the one that is in the front by the thermostat??
09-12-2004 | 08:07 PM
#12
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From: Sussex, WI
Re: 502 MPI VST Check
Temp sender is the one by the thermostat, a scan tool will tell you how many volts are being sent to the temp sender, If I remember correctly there should be 5 volts going to the sender, you can check this with a volt meter.
The temp sender then acts as a resistor and based on temp sends a modified voltage reading to the ECM so that the computer can make its adjustments.
Have you checked your plugs to see if you are actually running rich, also check the fuel rail to see if you have exceesive fuel pressure, could be a bad pressure regulator.
Twice as much fuel as normal is a lot of extra gas going into a motor, it should be fairly easy to figure out what is causing it if you really have that much extra fuel being used.
also, as far as the needle and seat, it acts like a float and bowl in a carb, if it was stuck open it would dump the excess fuel into #8 the same as a bad diaphram.
The temp sender then acts as a resistor and based on temp sends a modified voltage reading to the ECM so that the computer can make its adjustments.
Have you checked your plugs to see if you are actually running rich, also check the fuel rail to see if you have exceesive fuel pressure, could be a bad pressure regulator.
Twice as much fuel as normal is a lot of extra gas going into a motor, it should be fairly easy to figure out what is causing it if you really have that much extra fuel being used.
also, as far as the needle and seat, it acts like a float and bowl in a carb, if it was stuck open it would dump the excess fuel into #8 the same as a bad diaphram.
