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car idle temp gauge rising high

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#101 ·
shane1234567 said:
No fan whats so ever when motor is on or off,there is no plastic prong sticking out of the face of the dial,all i can say is it gose back to its original postion that your pic shoes when i turn the motor off
Click to expand...
Shane, the engine cooling fan should only ever run when the engine is running, or you have the ignition switched on position 2 (lots of red lights on dash).

If your temp guage does not have a stop (thin spike sticking out of guage face) it could be a slightly different guage as your car is a year newer.
 
Discussion starter · #102 ·
Right the muliplug was off ,done what you said with thre revs but the gauge did not drop,ill re possition the temp dial again and run the engine for 10 mins.I take it you want me to leave the multiplug on this time after re possitioning the dial again
 
#103 ·
shane1234567 said:
Right the muliplug was off ,done what you said with thre revs but the gauge did not drop,ill re possition the temp dial again and run the engine for 10 mins.I take it you want me to leave the multiplug on this time after re possitioning the dial again
Click to expand...
Where was the guage at when you ran it just now (e.g. just below half, on half, just above half, 3/4, etc)

Was it stable?
 
#105 ·
Right, lets just explain how the coolant system works.

The task of the coolant system is not to keep the engine cold, but to keep the engine at a constant temperature.

When cold the thermostat is closed and coolant bypasses the radiator allowing the engine to warm to temperature faster. Once the coolant reaches temperature (this will vary acording to the engine) the thermostat starts to open allowing coolant through the radiator cooling it.

When idling, especially in warmer weather the radiator fan is used to force cool air through the radiator. Without the fan, the coolant temperature will continue to rise until such a point as some part of the system fails.

If the fan isn't cutting in then either the coolant is not hot enough, or the sensor is damaged.

So how do we tell if the coolant is hot enough to cause the fan to cut in? This is the job the temperature guage plays. Of course if we don't think the guage is working then this makes the job even more difficult.

If we are not sure the guage is working, the best fix is to replace the guage with a known good guage. Bear in mind that no two cars will read the temperature exactly the same.

The key thing at this point is to know what we are trying to observe.
From cold, the temperature gauge should rise steadily and stabilise. Normally, this is just below half way. After a while the fan should cut in... The temperature should remain stable.
 
Discussion starter · #106 ·
it was stable just over half way whith no fan,but for some reason it rose by a couple of mm and stabilised while the fan was on,the funny thing was i watched it for a few mins to make sure that it was not going to rise any further,shall i put the multiplug back on and waite longer to see where it stabilises again,sorry about this.or shall i re possition the dials as you said and try again with the multiplug back on and see what happens
 
#108 ·
shane1234567 said:
it was stable just over half way whith no fan,but for some reason it rose by a couple of mm and stabilised while the fan was on,the funny thing was i watched it for a few mins to make sure that it was not going to rise any further,shall i put the multiplug back on and waite longer to see where it stabilises again,sorry about this.or shall i re possition the dials as you said and try again with the multiplug back on and see what happens
Click to expand...
Basically, we are trying to re-calibrate the guage.

To do this, we need the engine cooling fan running all the time. If you say it was over half way with the fan running, you need to reset the guage, a little lower.

Then run it again with the multiplug disconnected so the engine cooling fan still runs. We need to get to a stage where the guage shows like the one I drew the line on, just under half and stays there when you rev the engine to 2000, or it idles. Engine will need to be run for 10 minutes to get properly hot.

I think the reason it went a bit higher this last time was cos you ran it for longer and the engine was hotter at the start.

We will get there. . . .

OK, understand what you now have to do?
 
Discussion starter · #109 ·
please remember the fan has never come on when multicap is connected.Right i will let the engin cool down for a min,then ill put the multicap back on,find out where the engine stabilises with no fan as it dose not kick in.come back let you now.then take multicap off and se where dial drops to,then you will advise on the possition of needle dppending on where the needle stabilises while the cap of and fan was running is this correct
 
#111 ·
shane1234567 said:
please remember the fan has never come on when multicap is connected.Right i will let the engin cool down for a min,then ill put the multicap back on,find out where the engine stabilises with no fan as it dose not kick in.come back let you now.then take multicap off and se where dial drops to,then you will advise on the possition of needle dppending on where the needle stabilises while the cap of and fan was running is this correct
Click to expand...
No. We need to get the guage to read right first. You therefore need to reset the pointer again, so it is lower.

Then, run the engine again, with the cooling fan going (multiplug off) for 10 minutes, revving it every minute to 2000RPM for a minute, then letting it idle for a minute, then rev it. . . . . . . . .etc.

We need to get the temp guage to be like the one I drew - so the pointer stays just below middle when the engine is at normal temperature - fan on all the time.
 
#114 ·
shane1234567 said:
right games up pin snapped need to buy new temp gauge now in short brad how do i callabirate the new gauge mate with the motor sh...t sh...t
Click to expand...
Heh heh. Oh dear. That was what all the effort was for, trying to stop you buying a new guage.

The new guage will not require any calibration, as it will not have been played with.

Just make sure you get one from a 200 PETROL model.

We can then resume our fun and games.

New guage should just work and temp should be as my drawing when the engine is at normal temp.

Be careful up to then. I would personally drive the car with the multiplug off so the fan runs all the time, although this will make it use extra fuel. You have no idea how hot it is with no temp guage!
 
#116 ·
shane1234567 said:
nope only what the gauge said but we cant trust that
Click to expand...
OK.

Tomorrow, when the engine is cold, check the coolant level and top it up to spot on max mark. You can then monitor the level to see if it is leaking over the coming weeks.

Get a new guage and install it. Post back here/PM me.

If you drive the car in the meantime, disconnect the multiplug so the fan is always running and try to avoid driving it until you get the new temp guage.

Then we can establish the fan problem - not working.
 
#118 ·
If you want to install the dials on the new gauge, after verifing that the gauge works good, and the engine is warm, disconnect the gauge. Remove the needle, remove the dials, fit new ones. Do not refit the needle.
Fit the gauge and run the car for a few minutes (to make sure it's up to temp).
Then refit the needle in the position just below mid point. You do not need to apply lots of pressure. Providing it is pressed on enough so that it does not fall off it will work perfectly.
 
#119 ·
mate you send me a pm but since your box is full i ll paste my reply over here..
"did you notice smoke when the engine was on..? the shuddering seems quite weird to me..if it is repeated.. if the second time you started the car didn't shudder then i guess you shouldn't bother..
fill coolant to max and check for a while the coolant level..a week or so..just in case.."
 
Discussion starter · #120 · (Edited)
Every time i start the car from cold it struggles to start mate,shuddering, and cutting out a couple of times befor it stays running.Its almost like spark plugs are bad or leads are on there way out,but I have recently changed spark plugs and leads,so there is nouthing wrong there,but when it dose start and warms up it seems ok.when it turns over i cant give it any revs for about 20 seconds or it feel like it wants to cut out
 
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