Strange coolant temp

tenkfeet · Post by **tenkfeet** » Fri Aug 24, 2007 3:28 pm

I have a funny feeling my thermostat is gubbed, symptoms.

It appears to take a while to warm up from cold , though when I left it for an hour it was fine. When warming up it reached 85 then when down to 74 ish then back up .It normally runs at 86 degrees solid, today no matter how hard I thrashed it was 84 solid. Ran it up till the fan kicked in fine and drove it temp dropped to 84 and went down to 81 when I came off the gas.

To change it do you have to take the manifold off?

Coolant level is fine. Suggestions please ?

Is thie an excuse to go Honda ?

Rich H · Post by **Rich H** » Fri Aug 24, 2007 3:34 pm

Change the coolant sender they tend to do wacky stuff during its final few months. Thermostats tend to get stuck open or closed, it would either take ages to warm up or get scarily hot!

HTH
Rich

tenkfeet · Post by **tenkfeet** » Fri Aug 24, 2007 4:04 pm

I forgot to say the imobiliser light was flashing with the engine running at one point . Cleared when I turned off the engine and reset the alarm. Does that also act as a stack warning say if the sensor was gubbed.

I will take a look tomorrow , I have a feeling I could transpose the sensor plugs and see how it goes.

robin · Post by **robin** » Fri Aug 24, 2007 4:15 pm

The flashing red light is the shift limiter perhaps ... it comes on at lower speed when the engine is cold.

S2 uses just one temperature sensor - whatever is displayed on the dash is also whatever the ECU sees.

If you're going to go Honda, I'll have your engine

To test the stat you can get it up to temp, then cruise at 50 in top gear and see if the temp continues to drop - chances are it will drop right off the scale if the stat is stuck open.

This won't be doing your engine any good, so avoid heavy revs/loads until you get it fixed.

Cheers,
Robin

Rich H · Post by **Rich H** » Fri Aug 24, 2007 4:34 pm

Does that mean I was right? I'm confused? I just know I have got through loads of coolant senders

tenkfeet · Post by **tenkfeet** » Fri Aug 24, 2007 4:39 pm

robin wrote:The flashing red light is the shift limiter perhaps ... it comes on at lower speed when the engine is cold.

S2 uses just one temperature sensor - whatever is displayed on the dash is also whatever the ECU sees.

If you're going to go Honda, I'll have your engine

To test the stat you can get it up to temp, then cruise at 50 in top gear and see if the temp continues to drop - chances are it will drop right off the scale if the stat is stuck open.

This won't be doing your engine any good, so avoid heavy revs/loads until you get it fixed.

Cheers,
Robin

I will give that a go tomorrow thanks .

In the back of my mind I would not mind my engine going ping as I would be able to justify the expense to myself. Ok you have first dibs on the engine.

Rich H · Post by **Rich H** » Fri Aug 24, 2007 4:51 pm

Empty the coolant out and drain the oil.

It'll go "ping" (More acutately "Bang-clatter-clatter") PDQ

Baggy · Post by **Baggy** » Fri Aug 24, 2007 8:02 pm

If you remove the sensor cable and put it back on a few times it improves the connection. Mine was missreading when I got my car 3 years ago, bought a new sensor, thought I'd check the connection first & that fixed it & it's been fine since.

I kind of think that these connectors are designed to be under a bonnet and mostly dry. The elise engine cover vents allowing rain through can't be great for them because they're not a water resistant design. keep meaning to go round with some amalgamating tape or something but haven't

tenkfeet · Post by **tenkfeet** » Sat Aug 25, 2007 2:36 pm

Baggy wrote:If you remove the sensor cable and put it back on a few times it improves the connection. Mine was missreading when I got my car 3 years ago, bought a new sensor, thought I'd check the connection first & that fixed it & it's been fine since.

I kind of think that these connectors are designed to be under a bonnet and mostly dry. The elise engine cover vents allowing rain through can't be great for them because they're not a water resistant design. keep meaning to go round with some amalgamating tape or something but haven't

Just been out doing your test Robin and the only thing I did before going out was Baggys fine suggestion above

.The connector looked fine and dry . The car temp appeared in a normal time and was perfect temp ,86 throughout and when I booted it the temp dropped to 84 and recovered to 86 within 5 seconds .

I could not get the temp above 93 at all though it was a bit breezy when I tried.

So thanks for your advice guys , the gremlin has been excercised.

For now anyway.