Mechanic's opinion needed...

[Leo]

Some years of my dad's old Benz had plastic timing chain guides that would wear out, go out of time, and munch the engine. Using ANYTHING plastic, nylon, or rubber in a timing system is dumb as hell IMO. Seen plenty of timing chain motors go 250k without timing system service. I freaking hate timing belts of any kind.

I have only seen timing belts be a problem when not serviced.

When the Volvo cars got an overhead cam driven by a toothed belt, they scheduled inspection of the belt in a regular intervals and replacement pretty early, like maybe 40 or 50,000 miles. The preventive maintenance paid off, I never saw any of them get towed in with a bad timing belt. I saw many 2.3 Mustangs towed in with broken timing belts. Of course they were significantly higher mileage, but the preventive replacement intervals were not seen on the Ford manual. I changed my Mustang belt every 50,000 and never had to call for a ride home. Those were both quick and pretty easy to change the belts, not like today's cars.

 

[Lmo1131]

Thanks for all the comments and offer for hands-on assistance.

I’ve been distracted for a couple of days. Getting back to the Escort today l tried to test the TPS but it’s a tight fit, so thought l’d just remove it.

While doing that l discovered that the &@/?!% TPS mounting acres are ‘frozen’ in place after 35 years; the mounting holes are blind so l doubt that the Kroil l applied will penetrate. So it looks like the Throttle Body needs to come off so l can apply some heat to the screw bosses.

Guess what … can’t find base gaskets for the TB.

Funny (not) how a 30 minute job turns into a week long project.,

 

[thunderchicken]

@thunderchicken are you going to be racing next year?

Lord willing and the creek don't rise, I plan on it.
Engine spent the whole last year at our engine builders shop. Took longer than expected but the quality is worth it

 

[Destro]

Funny (not) how a 30 minute job turns into a week long project.,

This is why I mostly stopped working on my own stuff. Noting ever ended up working out in my favor.

 

[Lmo1131]

Well, some progress today. I took off the MAP sensor to give it a shot of electronics solvent, and when I did I discovered the rubber vacuum line was perforated, in several places. Probably not the best setup for the measuring pressure and sending it to the Engine Control Module. So I replaced it.

But the original symptoms are still there; not as bad, but still there. And time will tell, but I suspect gas mileage may improve a bit.

But something else revealed itself. At some point in the car's history (it's been in my family since new) someone inserted a resistor (or a diode (I don't know what either do)) into the wire that comes from the temperature sending unit on the water outlet (that turns on the electric cooling fan and the temp gauge on the dash).

It was a shoddy installation (I know it wasn't my dad, he didn't know anymore about electronics than I do); the leads on the ends of the component were bent-double and crimped onto the harness wires using a WAY over size crimp connector); it was then encased in a piece of shrink tubing that wasn't even shrunk onto the joint.

Can anyone identify what this component is, and why it might have been added to this circuit?

 

[thunderchicken]

That definitely looks to be a resistor. I can't say that I have ever seen one installed on a coolant temp sensor circuit. Maybe someone else will have some insight

 

[bobzilla]

Some years of my dad's old Benz had plastic timing chain guides that would wear out, go out of time, and munch the engine. Using ANYTHING plastic, nylon, or rubber in a timing system is dumb as hell IMO. Seen plenty of timing chain motors go 250k without timing system service. I freaking hate timing belts of any kind.

DOHC timing chains are really dependent on regular oil changes. Saw plenty of Hondas k series jump time by 100k because they over extended oil changes way too long. Timing belts I’ve never had an e issue with as long as you change them at the correct intervals.

 

[Brad69]

The mystery deepens!

 

[Lmo1131]

That definitely looks to be a resistor. I can't say that I have ever seen one installed on a coolant temp sensor circuit. Maybe someone else will have some insight

It has me stumped as well. I have the Ford Shop Manuals for this vehicle; Ford wiring diagrams are almost as perplexing, printed in black & white with no wire color designator index, and 'wires' crossing over each other with no indication that they are/are not connected... I'm assuming that if there is not a black "dot" at the intersection of two wires that they are not connected.



Connector that plugs into the temp sensor on the block. Ford Shop Manual indicates that jumping should activate the cooling fan.
It does not. So.... on the search for a relay. EDIT... guess I should check the voltage ahead of the resistor, just for giggles, if nothing else.

 

[Lmo1131]

That definitely looks to be a resistor.

Just confirmed by another person, as .36 ohm. I wonder if the cooling fan is ripping up the radio reception and this was installed to reduce "noise"... I don't know.

 

[thunderchicken]

It has me stumped as well. I have the Ford Shop Manuals for this vehicle; Ford wiring diagrams are almost as perplexing, printed in black & white with no wire color designator index, and 'wires' crossing over each other with no indication that they are/are not connected... I'm assuming that if there is not a black "dot" at the intersection of two wires that they are not connected.

View attachment 307220

Connector that plugs into the temp sensor on the block. Ford Shop Manual indicates that jumping should activate the cooling fan.
It does not. So.... on the search for a relay. EDIT... guess I should check the voltage ahead of the resistor, just for giggles, if nothing else.

View attachment 307223

Yes, you're correct that even though in the diagram two lines cross does not mean they connect. I don't know of any manufacturer that has any wire color designator. But they're generally easy to figure out.

 

[thunderchicken]

Just confirmed by another person, as .36 ohm. I wonder if the cooling fan is ripping up the radio reception and this was installed to reduce "noise"... I don't know.

Could be possible

 

[Ark]

Well, some progress today. I took off the MAP sensor to give it a shot of electronics solvent, and when I did I discovered the rubber vacuum line was perforated, in several places. Probably not the best setup for the measuring pressure and sending it to the Engine Control Module. So I replaced it.

But the original symptoms are still there; not as bad, but still there. And time will tell, but I suspect gas mileage may improve a bit.

But something else revealed itself. At some point in the car's history (it's been in my family since new) someone inserted a resistor (or a diode (I don't know what either do)) into the wire that comes from the temperature sending unit on the water outlet (that turns on the electric cooling fan and the temp gauge on the dash).

It was a shoddy installation (I know it wasn't my dad, he didn't know anymore about electronics than I do); the leads on the ends of the component were bent-double and crimped onto the harness wires using a WAY over size crimp connector); it was then encased in a piece of shrink tubing that wasn't even shrunk onto the joint.

Can anyone identify what this component is, and why it might have been added to this circuit?

View attachment 307132

What in the actual F...

 

[hopper68]

R=red
Lg=light green
T=tan
P=pink
Bl=black
Br=brown
B=blue
Y=yellow
O=orange
B/w= blue/white stripe
T/o= tan/orange
Br/w=brown/white stripe

 

[Creedmoor]

R=red
Lg=light green
T=tan
P=pink
Bl=black
Br=brown
B=blue
Y=yellow
O=orange
B/w= blue/white stripe
T/o= tan/orange
Br/w=brown/white stripe

You missed each colors values.

 

[indyblue]

You missed each colors values.

Not resistor color code, that’s the wiring color key.

Resistor code:

Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Grey 8
White 9

That looks like a 36 ohm to me
3 6 0 (zero zeros) & 2% tolerance

 

[Creedmoor]

Not resistor color code, that’s the wiring color key.

Resistor code:

Black 0
Brown 1
Red 2
Orange 3
Yellow 4
Green 5
Blue 6
Violet 7
Grey 8
White 9

That looks like a 36 ohm to me
3 6 0 (zero zeros) & 2% tolerance

Thanks, I havent kept up with the thread.

 

[Lmo1131]

Thanks for the information.

I still don't understand why jumping the temp sensor does not activate the fan - it should.

I pulled the cold air tunnel off so I could get to the radiator fan and relay.

Temp sensor in block - 0v across terminal (stone cold engine, so 0v was expected)
Main Harness/Temp Sensor Harness leg - 12.3v - with 36 ohm resistance
Main Harness (from temp sensor) to Fan relay - 12.3v to the relay.
Fan - disconnected harness - jumped motor directly to the battery - fans works
Harness, Fan to Relay - checks okay - checked with ohmmeter
Fan relay - solenoid tested good - closes circuit to the fan terminals. - checked with ohmmeter

So power to the relay, relay tested good - what I don't understand is; why the relay doesn't trip and energize the fan when I jump the temp sensor connector. Power to the fan relay is always hot (it would frequently turn on even with the key in the off position).

As a side-mystery; WHY is thee a resister in the circuit to begin with? As it turns out Ford used them in the Focus as well. Here's a video but there's not explanation as to what the resister does.



Regardless, I'm still without a fan (unless I rig up a jumper circuit).

 

[Ark]

Thanks for the information.

I still don't understand why jumping the temp sensor does not activate the fan - it should.

I pulled the cold air tunnel off so I could get to the radiator fan and relay.

Temp sensor in block - 0v across terminal (stone cold engine, so 0v was expected)
Main Harness/Temp Sensor Harness leg - 12.3v - with 36 ohm resistance
Main Harness (from temp sensor) to Fan relay - 12.3v to the relay.
Fan - disconnected harness - jumped motor directly to the battery - fans works
Harness, Fan to Relay - checks okay - checked with ohmmeter
Fan relay - solenoid tested good - closes circuit to the fan terminals. - checked with ohmmeter

So power to the relay, relay tested good - what I don't understand is; why the relay doesn't trip and energize the fan when I jump the temp sensor connector. Power to the fan relay is always hot (it would frequently turn on even with the key in the off position).

As a side-mystery; WHY is thee a resister in the circuit to begin with? As it turns out Ford used them in the Focus as well. Here's a video but there's not explanation as to what the resister does.



Regardless, I'm still without a fan (unless I rig up a jumper circuit).

If I'm reading that diagram right, the temp sensor is actually just a switch that closes when the temperature hits a certain range.



I don't think that's a variable resistance sensor that drives a gauge or supplies a signal to a computer. It's common for cooling fans to be driven by these simple heat-sensitive switches. This one appears to supply ground to the coil part of the relay, which looks to be supplied with 12v at all times. So the switch is actually grounding the relay to complete the circuit. Perhaps shorting the power lead on that temperature switch connector directly to good ground will complete the circuit, activate the relay, and power the fan? There's two wires on the switch, so it is grounded via wire to somewhere and not via the housing of the switch. So maybe that ground wire is bad somewhere? If you test continuity from the ground side of the connector to the chassis, is it good?

The cooling fan controller may have the wire going to it because it can also provide ground to energize the relay. Here's a question: Does the fan come on when you turn the A/C on? I think the controller may provide ground to bypass the temperature switch in order to command the fan on to draw air through the A/C condenser even when the engine doesn't need the fan for cooling yet. Most cars will force the fan on when you turn the A/C on.

 

[Lmo1131]

If I'm reading that diagram right, the temp sensor is actually just a switch that closes when the temperature hits a certain range.

View attachment 307272

I don't think that's a variable resistance sensor that drives a gauge or supplies a signal to a computer. It's common for cooling fans to be driven by these simple heat-sensitive switches. This one appears to supply ground to the coil part of the relay, which looks to be supplied with 12v at all times. So the switch is actually grounding the relay to complete the circuit. Perhaps shorting the power lead on that temperature switch connector directly to good ground will complete the circuit, activate the relay, and power the fan? There's two wires on the switch, so it is grounded via wire to somewhere and not via the housing of the switch. So maybe that ground wire is bad somewhere? If you test continuity from the ground side of the connector to the chassis, is it good?

The cooling fan controller may have the wire going to it because it can also provide ground to energize the relay. Here's a question: Does the fan come on when you turn the A/C on? I think the controller may provide ground to bypass the temperature switch in order to command the fan on to draw air through the A/C condenser even when the engine doesn't need the fan for cooling yet. Most cars will force the fan on when you turn the A/C on.

The connector to the coolant sensor SHOULD energize the cooling fan when a jumper is inserted between the two contacts - but it does not. One wire IS energized even with key off, the other is ground.

The cooling fan controller is supposed to energize the fan whenever the A/C is “on”, and at anytime coolant temperature exceeds spec’d limits - regardless if key is on or off. It does not.

This one has me tearing my hair out, what’s left of it.

My Ford Shop Manual says that the cooling fan controller is located behind the glove box insert - convenient, huh?

It’s not there … so tomorrow is going to be a royal PITA.