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It will take a few "drive cycles" for computer to learn new TPS voltages.
1 Drive cycle = heat up to operating temp, 190degF, then a cool down below 110degF
And make sure new TPS voltage is below 1volt, throttle closed, and 4.5volt or higher at WOT
TPS voltage is adjustable, the closed throttle voltage is very important
But not the problem.
DPFE sensor is used by the computer to control the EGR valve, since it is part of an Emissions system it is monitored closely, so instant CEL and codes if there is a problem.
You can remove the vacuum hose from the EGR valve and plug the hose with a screw or bolt, then drive the truck to see if it makes a difference.
EGR(exhaust gas recirculation) is only used after engine warms up, and then only when engine is under load, accelerating, cruising above 40mph, pulling a load or going uphill.
EGR cools down the cylinders as they heat up when under a load, when cylinders get hotter the combustion produces higher levels of NOx, adding exhaust gases slows this heating up so lowers NOx levels.
It also helps prevent pinging/knocking, pre-detonation, which is caused by gasoline self igniting in a hot cylinder before spark plug can ignite it.
If computer was opening EGR valve when you shifted into gear engine would stall, but that wouldn't be a DPFE sensor issue, DFPE sensor tells computer when EGR valve is open and how much it is open by a pressure difference in exhaust manifold.
It doesn't tell computer when to open EGR.
But block off EGR valve vacuum hose to test if EGR is opening when it shouldn't.
Would not start still means starter motor is cranking engine OK, but engine didn't fire up, right?
The charging of the battery makes me think there maybe something else at play here.
What is the RPM of the engine at idle, cold and warmed up?
Should be 1,100rpm cold
750rpm warmed up
Fuel injection can't use a Choke Plate like a carb did, no Jets to sucks extra fuel from.
So fuel injection computer must run the engine in Choke Mode while engine is cold, it detects a cold engine using the ECT(engine coolant temp) sensor.
ECT sensor is only used by the computer, Dash temp gauge uses a temp sender, looks similar but not interchangeable.
When you turn on the key the computer boots up, opens IAC Valve all the way and looks at ECT temp, first things it does.
If ECT shows below 140degF it will add more fuel to start engine, Choke Mode, the colder the temp the more fuel it adds for starting.
Liquid gas won't ignite from a spark(yes, movies are wrong, lol), only gas vapor will ignite with a spark, this is the reason for a Choke plate or Mode to start a cold engine.
You need about 30% vapor to start the engine, the colder the engine the less the gas will vaporize, say at 50degF gas is 10% vapor when pulled from jets or sprayed from an injector, so you need to add 3 times more gas to get to that 30% vapor level to start the engine.
As soon as engine starts cylinders get hot and gas vaporized better as it is pulled into hot cylinders.
The air pre-heater, cover around exhaust manifold, is used to help vaporized more of the fuel during warm up, so engine warms up faster, it doesn't help in starting engine, it aids in engine warm up after starting, it also would not cause stalling.
ECT sensor can be test with volt meter and pin.
ECT sensor will have TWO wires, Sender only has ONE
One of the wires will have 5volts(like TPS) when key is on, the other wire will have lower voltage related to the temp of the sensor.
Voltages are here: http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0996b43f/80/20/25/6d/medium/0996b43f8020256d.gif
These will not be exact, but should be close.
Now if your ECT sensor was broken and showing low voltage(under 1 volt, warmed up engine) all the time, then computer would think you are just restarting warmed up engine all the time and wouldn't run engine at a high idle, wouldn't add extra fuel(choke) and engine would stall when put into gear because it doesn't have enough vapor to stay running
1 Drive cycle = heat up to operating temp, 190degF, then a cool down below 110degF
And make sure new TPS voltage is below 1volt, throttle closed, and 4.5volt or higher at WOT
TPS voltage is adjustable, the closed throttle voltage is very important
But not the problem.
DPFE sensor is used by the computer to control the EGR valve, since it is part of an Emissions system it is monitored closely, so instant CEL and codes if there is a problem.
You can remove the vacuum hose from the EGR valve and plug the hose with a screw or bolt, then drive the truck to see if it makes a difference.
EGR(exhaust gas recirculation) is only used after engine warms up, and then only when engine is under load, accelerating, cruising above 40mph, pulling a load or going uphill.
EGR cools down the cylinders as they heat up when under a load, when cylinders get hotter the combustion produces higher levels of NOx, adding exhaust gases slows this heating up so lowers NOx levels.
It also helps prevent pinging/knocking, pre-detonation, which is caused by gasoline self igniting in a hot cylinder before spark plug can ignite it.
If computer was opening EGR valve when you shifted into gear engine would stall, but that wouldn't be a DPFE sensor issue, DFPE sensor tells computer when EGR valve is open and how much it is open by a pressure difference in exhaust manifold.
It doesn't tell computer when to open EGR.
But block off EGR valve vacuum hose to test if EGR is opening when it shouldn't.
Would not start still means starter motor is cranking engine OK, but engine didn't fire up, right?
The charging of the battery makes me think there maybe something else at play here.
What is the RPM of the engine at idle, cold and warmed up?
Should be 1,100rpm cold
750rpm warmed up
Fuel injection can't use a Choke Plate like a carb did, no Jets to sucks extra fuel from.
So fuel injection computer must run the engine in Choke Mode while engine is cold, it detects a cold engine using the ECT(engine coolant temp) sensor.
ECT sensor is only used by the computer, Dash temp gauge uses a temp sender, looks similar but not interchangeable.
When you turn on the key the computer boots up, opens IAC Valve all the way and looks at ECT temp, first things it does.
If ECT shows below 140degF it will add more fuel to start engine, Choke Mode, the colder the temp the more fuel it adds for starting.
Liquid gas won't ignite from a spark(yes, movies are wrong, lol), only gas vapor will ignite with a spark, this is the reason for a Choke plate or Mode to start a cold engine.
You need about 30% vapor to start the engine, the colder the engine the less the gas will vaporize, say at 50degF gas is 10% vapor when pulled from jets or sprayed from an injector, so you need to add 3 times more gas to get to that 30% vapor level to start the engine.
As soon as engine starts cylinders get hot and gas vaporized better as it is pulled into hot cylinders.
The air pre-heater, cover around exhaust manifold, is used to help vaporized more of the fuel during warm up, so engine warms up faster, it doesn't help in starting engine, it aids in engine warm up after starting, it also would not cause stalling.
ECT sensor can be test with volt meter and pin.
ECT sensor will have TWO wires, Sender only has ONE
One of the wires will have 5volts(like TPS) when key is on, the other wire will have lower voltage related to the temp of the sensor.
Voltages are here: http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0996b43f/80/20/25/6d/medium/0996b43f8020256d.gif
These will not be exact, but should be close.
Now if your ECT sensor was broken and showing low voltage(under 1 volt, warmed up engine) all the time, then computer would think you are just restarting warmed up engine all the time and wouldn't run engine at a high idle, wouldn't add extra fuel(choke) and engine would stall when put into gear because it doesn't have enough vapor to stay running
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