royunion
Active Member
Does anyone know where the engine speed sensor (ESS) is or would be on a mechanical IP 6.5 Humvee /van motor??
On the DS4 it is part of the optical sensor but on the older engines DB2 it was found In the oil pump drive which is covered on humvee or van motor by the turbo, so the ESS must be elsewhere as a signal for the PCM to control transmission shifting
I have tired now of the PMD - lift pump - connector cable fight.
Even rotary vane lift pumps like the Carter p4601hp is now made in China and the has been dropped to 6 to 9 psi
And the reality is more like closer to 6 psi or below. Even new E8257 does not produce spec pressure long and the gets weak fast
I put on a sure cure lift pump kit that pushes a true 18 psi and I see it on the gauge
However as the lift gets weak it makes the PMD draw more current and the connector in the cable at the PMD looses temper and has a weak electrical connection ang it can cause cut outs until the connector is replaced.
Now that I have constant Consistant strong psi to the IP the current the PMD draws and the signal to the fuel solenoid is way down like it should be with a really responsive throttle and acceleration
But I am sick of this and I will convert it mechanical IP or put in the gas 5.7 I have
So I have not been able toocate humvee schematics or solid information on how the automatic 4L80E on the humvee is wired or Controlled.
So does anyone know - without guessing where the ESS is and where I can one or verify as some pages have said it is the first speed sensor on the 4L80E itself
On the DS4 it is part of the optical sensor but on the older engines DB2 it was found In the oil pump drive which is covered on humvee or van motor by the turbo, so the ESS must be elsewhere as a signal for the PCM to control transmission shifting
I have tired now of the PMD - lift pump - connector cable fight.
Even rotary vane lift pumps like the Carter p4601hp is now made in China and the has been dropped to 6 to 9 psi
And the reality is more like closer to 6 psi or below. Even new E8257 does not produce spec pressure long and the gets weak fast
I put on a sure cure lift pump kit that pushes a true 18 psi and I see it on the gauge
However as the lift gets weak it makes the PMD draw more current and the connector in the cable at the PMD looses temper and has a weak electrical connection ang it can cause cut outs until the connector is replaced.
Now that I have constant Consistant strong psi to the IP the current the PMD draws and the signal to the fuel solenoid is way down like it should be with a really responsive throttle and acceleration
But I am sick of this and I will convert it mechanical IP or put in the gas 5.7 I have
So I have not been able toocate humvee schematics or solid information on how the automatic 4L80E on the humvee is wired or Controlled.
So does anyone know - without guessing where the ESS is and where I can one or verify as some pages have said it is the first speed sensor on the 4L80E itself
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