My gauge has been dodgy for a while, before and after my HGF nearly 12 months ago. It takes forever to get the middle (normal) and normally only gets there in traffic when on a run it'll stay around the bottom 2 bars. Finally today while driving it dropped to the bottom and "restricted performance" light came on. Can this be related? Any ideas on what it come be?
Thermostat perhaps, but would this bring the light on also?

 

Yes, there is a fault code for not getting up to temperature in a reasonable period of time, so the restricted performance can be an indication of this. An OBDII code reader can confirm this.

It is likely your thermostat. Over the long term, running your engine too cool will cause sludge buildup and possibly other engine problems.

 

Its the thermostat. Just went through this identical situation. $12 bucks, New 185 degree thermostat, and 10 minutes later I was good to go.

 

Ok guys thanks, gonna get her plugged in tomorrow to confirm. Can a new thermostat be easily fitted? Any guides?

 

Piece of cake... Let engine cool down completely, leave cap on expansion tank, loosen and remove 3 small bolts on thermostat housing - there will be some coolant loss so be prepared -, remove housing and old thermostat, insert new thermostat with giggle pin at 12 o'clock, replace housing and bolts. Check coolant level and top off. That's about it.

 

Little update guys....what do you reckon now?


Ok plugged in and confirmed no error codes what so ever, so its not the thermostat.
A pressure test was then done on the cooling system, started at 10psi and went down to 8psi within 30mins, so this would say there is a leak. The car was then started and ran smooth with no white smoke coming out the back. However coolant could be smelt within the engine bay, no drips or coolant could be seen however. I have had the pipes replaced in the supercharger, so I doubt unless of a weak clip the leak is coming from this area, any other ideas where to look? It must be burning off somewhere? Or could it be coming out the overflow tank if the header tank is still to full?

 

If you had a restricted performance message, you had code(s), but they were not stored. You need to get a code reader on when the message appears.

Not saying you do not have a leak, but your thermostat still sounds highly suspect. This is not an expensive item and it should be replaced.

 

When I asked about the thermostat being suspect the garage bloke said I wouldn't be getting hot air from the blower if this was the case therefore thermostat being ok.....

 

I'm with WhiteXKR on this one. It is not that your car doesn't heat up eventually - it probably will with enough driving. But the engine may not ever be getting up to proper operating temperature. Replace your thermostat. At least you could cross that off you list, know that is done for the near future, and without spending much to do it. BTW: When was the last time it was done?

 

Never had a Thermostat replaced while I've had the car 7 years, probably longer than this

 

There is you answer staright away ;o]
Get that thermostat replaced pronto!
Thesee are a service item and should be replaced every three year or so when the coolant is replaced.
The expansion tank pressure cap should also be replaced.

As has been said, you will still get heat of sorts but the engine is not getting up to proper operating temperature.
This is a 'fast heat' design engine and it is bad to operate it below proper temps.
Yoy get a bad sludge build up in th engine, sludge in the oil, will increase your fuel consumption quite a bit.

When the pressure test was done, it should be pumped up to 17psi on a cold engine.
This is a couple of psi above normal working temp. of 15psi to test system for leaks.
While it is pumped up, use a bright light to check around the water pump,
thermo tower, thermo front housing, heater pipes and in your case, all super charger pipes and secondary coolant pump.

If it still continues to loose pressure, it's time to have a combustion sniffer test done to see if their are any combustion gasses leaking into the coolant.

 

Ok Thermostat ordered on your recommendation, will be here tomorrow and then I will fit, anything I need to know about fitting? I take it I don't need to worry about getting air into the system?


Then I will book it into the garage that did my HGF work for them to hopefully find that leak.


Will report back tomorrow if the gauge has been fixed by the thermostat, fingers crossed.

 

Fitting thermostat is straight forward.
You will first need to either drain of enough coolant to below the rad hose level,
or as i do suck it out with a vacuum pump....I hate mess ;o)
be careful witht he three bolts holding the thermo plastic cover.
Sometimes as this gets older and if it has never been reoved before, the screws can sieze in the little brass captive ferrules in the main body of the thermo housing....this happened to me with two of them!
When replacing them, use a little dab of anti seize and don't overtighten them!
The cover doesn't do the sealing, the rubber 'O' seal around the thermo does.
Make sure the little 'jiggle pin' in the thermo is at 12 0'clock.
When refilling coolant through expansion tank, leave off the screw cover of the thermo tower to allow any air to escape.
Squeeze the rad outlet hose gently and allow to settle.
Make sure level in thermo tower is at the top and replace the screw cap.....you will need a 10mm
Allen wrench and DON'T overtighten it ;o)

Your temp gauge may be a seperate issue.

 

It's most likely the thermostat staying open which will cause poor fuel economy and it will lead to engine sludge, etc etc as listed above. It can be the temp. sensor and there are ways to check the ohms with a meter vs coolant temp and compare it to a factory chart, but I think I'm personally aiming for the thermostat. My 97 is suffering the same issue & I haven't had a chance to get around it.

 

Just a quick update, Thermostat replaced, problem solved, thank-you everyone for your help in this.
Cheers....

 

Hi im going through the same issue. I installed a new thermostat not knowing about the giggle pin. and im having the same issues. where is 12 oclock on the housing ? and would the wrong position render the thermostat faulty ?

 

I guess in the world of digital clocks, it is no so apparent where 12 o'clock is!!! Get the point?

 

It was a rather shocking question . . .


Maybe not in Boca Raton, but in Orlando, it is when both Mickey's big hand and little hand are pointing up!!

 

 

If the jiggle pin was installed upside down (six o'clock position), it might have interfered with the flow of air out of the system during refilling. Even if it did, this small amount of air should eventually work its way out to the overflow tank. If you don't have any overheating problems after refilling, you should be good.