That is exactly what I meant.

Ford calls it a ECT sensor.

I just reference it like Audi or BMW. CTS. Coolant temperature sensor.



Now I do have some questions about this sensor, specifically on a manual 2000 7.3.

I have read that my truck, being a manual, has two CTS sensors. Like my e30 does.

One for the gauge reading, one for the PCM to reference.

IS THIS IN FACT TRUE?
From what I have read autos only have one CTS, for the gauge only, and that the PCM's input for temp. is based off of the engine oil temp?

 

It is true. The one on the water pump is for the gauge.

 

Does anyone happen to have a part number for this second cts sensor?

Where is it located?

I have read two different places?

 

Sensor that sends coolant temp to the dash (ECT) is part number F65Z-10884-AA aka SW-5130 aka 36447 when found at Advance, Amazon etc. Mounts on top of water pump. All trucks the same on this one.

Sensor that sends engine temp to the PCM (EOT) is part number 3F1Z-12A648-A aka DY-1144. This same sensor is mounted in two different locations depending on transmission. Naturally, of course, why not. On autos it is on the back of HPOP, but on manual trucks it is mounted above CPS at location show below. Pics courtesy of SkiSkyJason LLC.

 

I don't have a pigtail or connector at all for that sensor. Manual location as I have a 6 speed.

Could I have an auto engine wiring harness swapped in place from a previous owner?

Also when I am cranking the truck I hear what seems to be a relay just in the cabin fuse panel area that goes click click click reall fast but the truck fires and obv the clicking stops.

What relay would you suspect? Location?

I want to figure out this ect sensor to PCM issue, if I am even equipped with one.

So you are stating auto do in fact have a ect sense that inputs to the PCM? As if located behind the hpop?

I'll in the morn.

Input is really appreciated about both questions at hand.

 

Automatics: No ECT on the OBDII port... at all... ever. Your SCT is reading the OBDII port, that's it's "magic". Trying to read ECT on an automatic will have you pulling over for a ghost overheat.

Manuals: I have a manual 7.3L engine on a pallet, the ECT sensor to the OBDII port is on the passenger side of the face of the engine, above the harmonic balancer. This is not to say all SDs with manual transmissions can be counted on to show the Engine Coolant Temperature on the OBDII port. Engine Oil Temperature is always close to ECT.

ICP: It's a Dorman, and your IPR is reading 9% at idle, That is on the verge of a low IPR for idle, but not out of spec. I don't trust that sensor to be accurate, or to not stall the engine when somebody cues up a CB radio in close proximity.

Codes: I would clear them all and address the frequent flyers (the ones that come back).

For useful info, click the OBDII tools link and the last link in my signature line.

 

So many times it seems easier to swap parts than to trouble shoot.

The benefit to investing in a good quality scanner with the ability to record PID's is that you then can learn how to repair your truck, instead of guessing and spending money.

You also can then get the benefit of all these folks on this and other forums who can advise. They can only help so much without the info, though.

 

The very fast paced clicking noise coming from just below the radio (that is where it sounds like it is being produced from) is def related to my starting issues. I crank the truck,

2 new batteries
new starter
connections are good/clean
Fuses are new


the clicking is very rapid, and then once it stops the truck will fire instantly. Simple as that.

The truck is cranking very fast.

I thought it was the idm relay.

But the post below states for my 2000 the relay would be located in the engine bay fuse box.

https://www.ford-trucks.com/forums/1...ion-relay.html

I have read about three relays below the radio, in a box.

1 large (turn signals) and 2 smaller ones. Fuel pump and what?

Please advise and thank you for your help.

 

IDM located driver side wheel well near hood hinge remove front wheel and pull back rubber mud shield

 

Not idm module my friend. Relay. Idm relay.

Ok.

What relays would click rapidly while cranking in the general area of the radio/cup holder?

If it is the fp relay, then my understanding is the fp relay circuit is closed by the PCM "ground"

If the Pcm's ground is bad then it would cause a lack of power to the associated relays connected in that circuit and would cause the relays to click while cranking.

While cranking this bad ground connection is overcome and the relays will stop clicking due to proper current and the truck will start.

How is the idm relay powered?

Sorry for my lack of terminology or understanding of the systems.

Please advise and thanks!!!

 

Any thoughts?

 

Came out to the truck last Sat and of course the symptoms persisted.

Crank Crank Crank and no start. This time without the rapid clicking from behind the radio area.

No apparent fuel being delivered.

So I had enough, and the only area left to inspect/replace was the IDM itself.

First off taking the inner fender liner is pretty crappy. For anyone who hasn't done this yet, disconnect the wire loom push connectors first, then remove the plastic push pins that are located right under the front of the door/ above the side steps.

After that, then you can go about removing the bolts.

After disconnecting the harness plug and getting the IDM out it was apparent water intrusion had taken place for some time now but it wasn't awful.

With the IDM unplugged I cranked the truck, simply to see if my symptoms stayed identical. They did.

I then took the wire connector gasket out of the IDM and cleaned/dried out the area. Plugged back in the IDM and the truck started.

I have gone about replacing the IDM with a new unit and the truck has started every time since.

I still believe there is a parasitic draw issue.

 

You seem fairly comfortable with electrical stuff, so I will suggest one method to check parasitic draw. Radio shack and other electronic suppliers have power resistors --buy a 1 ohm, 5 or 10 watt power resistor.

Lift the two negative battery terminals.
Use alligator clamp test leads to connect the resistor between one of the negative cables and the battery negative.
Then measure the voltage across the power resistor.
This voltage (usually less than 1 volt) equals the parasitic draw value in amperage.
I=E/R (Ohm's law)
A value of less than .5 volts (therefore .5 amps) is common, my truck is .2 amps

I suggest you disconnect the engine ground (conveniently located on the rear side of the passenger head) and sand or file the surface, inspect the terminal for corrosion), reinstall cable.

Remove the starter cable terminal and any other large cable terminals and inspect/clean and reinstall.

Those clicking relays are symptoms of low operating voltage, probably from a loose/corroded connection. There are other smaller ground connections on the driver's side fender and under the dash on the firewall. You can do some ground cable tracing to find some.

If you are really serious about this issue, you can purchase downloadable wire diagrams for your truck that show all the ground connections on the internet--just google.

The ground from the alternator is not a very good connection. You can install a supplemental ground cable from the alternator mounting bolt to the battery directly or to a large battery ground cable in the engine area. This is not your problem in this situation though.

Good luck, Larry

 

Heavy stuff there, Larry. Thanks for the volunteered info

 

What would cause the fuel system to lose prime?

Meaning is there a specific check valve integrated into the system?

Any knowledge would be great.