Ford Focus Engine Light Falsely Reading Over-Heating

[v530anh]

My car is a 1999 Ford Focus Zetec 1.8 Ghia Petrol 118,500 miles

RAC guy says the engine (DTC D073 Invalid or missing data for engine coolant) reads over heating but fans working and car temp and coolant OK. Said something about a faulty sensor on top of engine. 

Engine light goes off when car has cooled down, so OK for short journeys, but not OK for medium to long journeys.

If anybody can point to a youtube video or a page in the Haynes manual, I would appreciate it.

P.S The temperature dial sometimes goes to zero and the coolant temperature.

[Russ]

Not wanting to sound cheeky but search YouTube for whatever it is you want a link to ...... coolant temperature sensor - engine temperature sensor ?  You don't exactly state what you want a link to.

Coolant temperature sensor - https://youtu.be/jrLtFKPDcm4

Cylinder head temperature sensor (2001 focus) - https://youtu.be/VX4XCMjE4bM

 

[v530anh]

1 hour ago, Russ said:

Coolant temperature sensor - https://youtu.be/jrLtFKPDcm4

This is what I found, but the guy who posted this, points to the engine sensor. Which is very easy to find in the 1.6, but not so on the 1.8 even the Haynes manual does not show a picture of the engine sensor and it seems to be much more difficult to find.

 

1 hour ago, Russ said:

Cylinder head temperature sensor (2001 focus) - https://youtu.be/VX4XCMjE4bM

I guess this video is made by someone who knows cars. So remove coolant and PSU reservoir, remove wheel, loosen tensioner to remove aux. belt, then remove alternator, and there it is! Suddenly I feel like a two year old who is learning ABCDEFGHIJKL etc!

This video did have an interesting comment:

qualityrenov2 months ago

lucky you guys with Ztec engine! Duratec engine ,for the second generation foci, has the Cylinder head temperature sensor between cylinders 2&3. needs either a special tool, extra deep deep deep deep 19mm socket-good luck finding one, or , you would have to go through the nightmare or removing the valve cover. I love my focus and I baby it and all, but, lets face it. the engine was designed by a mentally incapacitated mechanical engineer.

 

I think the wire that RAC guy showed me was to the sensor. This may be expensive if I took it to a garage and it may still not solve my problem. Any advice would be welcome, perhaps I will just leave it as I use it mostly for short trips, and for longer trips I would just have to rest the engine occasionally....

[Russ]

Just read a webpage that states the sensor on the 1.8 is apparently on the back of the engine block so I'm assuming the 2nd video will be the correct one?

[v530anh]

Car would not start, temperature dial went into red on a cold early am.

Opened bonnet, followed temp sensor wire to connector, and just squeezed it in the hope of fixing a loose connection.

Did seem to work, temp dial not miss behaving. Though I have not taken the mk1 on a long journey it seems problem solved.