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Humvee engine speed sensor

royunion

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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
 
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Will L.

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On the n/a one it was the oil pump drive. But centermount turbo made it get moved to crankshaft position sensor (CPS). The ds4 trucks need a 3 wire CPS.
But the speed sensor that feeds the tcm (basically the ecm but only thr trans is controlled instead of both) is a 2 wire CPS. It needs the newer lower timing gear and 4 point reluctor wheel that is used in the ds4 engines.

Are you running a centermount turbo? If not and you want the ds4 still- then use the oil pump drive ess.

Where I live DMV kills the ds4 to db2 conversion by smog law. So no hummer newer than 95 and no pickup newer than 93 for me- I won’t deal with ds4 headaches again.
If you were allowed to do it where you’re at, go DB2 to and end all the headaches.
 

royunion

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Well that's not good news

The smog laws is not an issue as I have a way to satisfy the sensor inputs except the ESS off the optical sensor so I can't remove and change the crank sensor so I can use a mechanicall IP and let the PCM still and it is unlawful to use an OEM set up on the engine so long as emissions do not in rease and things like the OEM doc remains.

I will figure out something
 

Will L.

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If you can weld aluminum, maybe pull the timing cover and add a pipe and one hole bracket on the passenger side into the cover? Basically add a second cps. Leave factroy one where it’s at and the new hole for the hmmwv 2 wire cps.

I’m not sure what is involved in using the TISS @THEFERMANATOR ?

Maybe a custom reluctor wheel that bolts to the belt drive pulley off the crankshaft? Or even replacing the 4 bolts with studs and nuts so the studs stick out far enough and make a mount for the extra sensor.

Wacky but possible, especially if you are a 6.2/ 6.5 parts collector, again welding capability required:
If you are running a centermount turbo so the ESS won’t fit, then you aren’t using the manual fuel pump hole as a oil return for the side mount turbo. So you could add the fuel pump rod and manual pump, but instead of moving fuel set up a sensor in the pump body? It pushes once per revolution. Then use a tachometer cycle corrector to get the count up to 4.

Mod valve cover for oil fill, replace oil
Fill spout with shaft driven 8 point reluctor off ip drive gear bolts. Mount sensor to the plate you make for the new cover...

Join the dark side- we don’t just have db2 pumps, we have cookies!!

Good luck. Share what you figure out please for others so they don’t feel the pain as bad.
 

royunion

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The fuel pump idea is the winner!! I can machine up a sensor mount on one of those cheaper rebuildable sbc mechanical pumps and turn piston energy of the pump into rotational energy
 

Will L.

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Ok. Sounds interesting- post pics.
I was thinking just set the sensor so when the arm moves part of it could pass in front of the sensor area, then away after the stroke. I did something similar years ago on a recycled plastics separator. Anything that has enough movement to go in front of the sensor enough to be in the magnetic field, then out of it will trigger it.

Another option I forgot to mention
The cs30 and cs44 alternators have a pickup in them. You don’t have your rig listed, but iirc all the gmt400 pickups, vans, suburbans, etc use the alternator pickup to trigger the tachometer. That’s why it’s important to ensure exact pulley size on them when replacing a bad alternator. Maybe you can tap that source.

There is also aftermarket ones. There are tachometer kits that have a sensor which uses a big hose clamp to affix it to alternator or the like and reads off the pulley- but if you need it very accurate you have to have known speed to calibrate it by. The obd2 port can pick that up with a scanner from the cps.
 

FellowTraveler

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Ok. Sounds interesting- post pics.
I was thinking just set the sensor so when the arm moves part of it could pass in front of the sensor area, then away after the stroke. I did something similar years ago on a recycled plastics separator. Anything that has enough movement to go in front of the sensor enough to be in the magnetic field, then out of it will trigger it.

Another option I forgot to mention
The cs30 and cs44 alternators have a pickup in them. You don’t have your rig listed, but iirc all the gmt400 pickups, vans, suburbans, etc use the alternator pickup to trigger the tachometer. That’s why it’s important to ensure exact pulley size on them when replacing a bad alternator. Maybe you can tap that source.

There is also aftermarket ones. There are tachometer kits that have a sensor which uses a big hose clamp to affix it to alternator or the like and reads off the pulley- but if you need it very accurate you have to have known speed to calibrate it by. The obd2 port can pick that up with a scanner from the cps.
Yep!
 

royunion

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The fuel pump idea is the winner!! I can machine up a sensor mount on one of those cheaper rebuildable sbc mechanical pumps and turn piston energy of the pump into rotational energy
Ok. Sounds interesting- post pics.


Another option I forgot to mention
The cs30 and cs44 alternators have a pickup in them.
I am aware of the alternator solution but my object is to replace the CMP signal and electronically fudge up a high resolution signal so the timing stepper motor can still work so the change won't throw 251, 370 and 216 codes.

In essence leave the current PCM thinking a good ds4 circuit still exists and that can done with a proper cam signal geared properly to sync with cam rotation

That way it will never know its running on a mechanical ip
 
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