Ok I installed new cps still no tach on crank. I don't understand why.

 

I got it to run? Don't know how it went from no tach to bouncy tach to running but I have lost my temp and oil "gauge"

 

First thing to check is the connectors for the oil pressure and coolant temp senders. Might've gotten bumped loose while working under the hood.

 

^^^^ X 2 . The Oil pressure sender is not expensive or really important .

IIRC there are 2 coolant temp sensors , only one is for the gauge.

 

Truck went back down. It started dropping cps signal and after about 30 seconds cut out an I left it at Casey's across the street from subway

 

Pulled it home 6 miles in 5th gear no tach signal motor turns 1800 rpm in 5th at 55 mph

 

Going to pull the engine harness out of the 97 f superduty see if that does it

 

You guys ever pull the engine harness out of one of these? How hard is it? Pull the breather ***., harnesses cps vc, ipr,icp. Is that all?

 

Its pretty easy really. The IPR and sensors on the fuel bowl disconnect on the plug on the pass side of the bowl.

 

just a FYI. Flat towing a ZF5 will result in buying a new trans

 

Well drove it to work today I hope it makes it home at 330 am. I pulled the wire harness out of the f-sd hit the key boom started right up.

 

1 week no issues I think it's good now.

 

Glad it is working for you now. Did you swap any sensors when you did the wiring harness?

 

No I didnt. The only issue I have is since I changed the harness I have no control of rpm under 1000. It jumps from 650 to 1000

 

Called "dead pedal". As you might know, the accelerator on our trucks is just a "volume ****", a variable resistor. There's also a switch that closes as soon as you start moving the pedal. The PCM needs to see that switch change from open to closed (0 to 1) before it takes the engine above idle. Sometimes the switch doesn't close until you've pressed the pedal a ways quite a bit, which results in what you're experiencing. You can adjust how the switch closes, either by bending the tab that engages it, or by loosening the switch and moving it a wee bit in its mounting holes. Some have even elongated the mounting holes, or made an adjustable "stop" on the tab. This will make the switch close "sooner" in the pedal travel.

But DON'T over-adjust it. If it's over-adjusted, and the switch never opens (tab never presses it), you'll NEVER get off idle.