Temperature guage and fuel economy

[kellen]

Hi All

I have a 98 Ex in standard spec. We have owned it since almost new. I have an unusual issue in that the temperature guage needle indicates well below zero when cold and even when the vehicle is at running temperature the needle only indicates just above zero. At the same time I appear to have a drop off in fuel economy (I don't measure this but it just seems to use a lot more fuel). I have looked at various threads and they talk about a temperature sender and also a sensor. If it is the first i can understand it impacting on the guage, but would that impact of fuel economy? Hmmm, I wouldm't have thought so. If it is a faulty sensor would that impact the temp guage? Any other thoughts? I will also change the air filter as if that is blocked it certainly wont help!

I love my Ex and notwithstanding the Porsches and Lotus I have owned, this is the only vehicle I have formed an attachment with. As a result I am about to spend lots of cash on a new set of tyres next week. My Goodyears are not completely worn out but a couple are close. Am going for a set of 265 70 16 General Grabber AT's....unless anyone has a negative view on this. I have read a lot of threads on tyre choice. Has anyone used AT's longterm? Or RTS's for that matter as they are more road orientated?

All thoughts and experiences greatly appreciated.

Cheers

Neil

 

[Howard]

There are two sensors for the temp. One does the gauge on the dash and the other feeds the ecu with a reading. If both are giving low readings then I would suspect that the thermostat has failed in the open position, meaning that the engine does not get to normal temperature.

 

[kellen]

Ah thanks Howard. That could explain the higher fuel consumption I guess....if the engine is colder the ECU is pumping in more fuel?

Cheers

 

[janolsson]

As howard has s is classic symptoms of a t stat remaining open.

If you are going to replace go for Original ford replacement. The dealer may tell you you need to order the oring also but I got one in the box with the new stat. So just order the stat and if it hasn't got the o ring I have one you can have
come to think of it I have a used but good condition housing with sensors (worked before being stashed in the garage) if you manage to muller yours

If you search my threads for t-stat you might find the uk part number to

Jan

 

[kellen]

Thanks Jan. What is confusing me is that the heater does get hot.....eventually....even if the temperature guage is registering just over cold. That said, the Ex is 15 years old and has never had a new thermostat. It probably makes sense to replace it anyway. I note you have a good used one just in case.

Many thanks

Neil

 

[kellen]

Thanks Jan and Howard. I have installed a new OE tstat and it has sorted the temperature guage reading. Hopefully this should sort my MPG as well. I have also installed new anti-roll bar bushes and drop links......60K miles since I last did it. What a transformation.

Cheers

Neil

 

[janolsson]

Yey

Did the stat come with the o ring??

 

[kellen]

Hi Jan

It was an original Ford item in a Ford box and came with the O-ring. No hassle fitting. Thanks for your help and support.

Neil