Erratic Temperature gauge 1.6 Sx

[Jirwin]

Hi, have done a search on this and come up with a solution but its for a different engine. I would like a definitive answer for my engine, a 1.6 16v, as hopefully this will enable me to understand and sort my problem more rapidly.

Finished work tonight and on way home noticed the temperature gauge climbed to 90, as is normal, but then started randomly dropping back down towards zero. It never exceeded 90' at any point and after a while it was fine. I have checked the coolant which is between the marks and had a quick look round the engine bay for anything untoward and found nothing.

What am I looking at to solve the problem? I will be doing the work myself, I'm proficient with tools but don't have the knowledge to diagnose the problem. If anyone comes up with any solutions do they have pics of the part on the 1.6 engine so I can see where it is to change it?

I need my car in a day to drive from Lincoln to Southampton, if I haven't sorted the problem by then due to time constraints/parts etc will I be risking damage to the engine taking it on such a long drive?

Thanks in advance for your help, James

 

[m0rk]

Sounds like the thermstat has stuck open

did the temp drop as you increased speed or had the heaters on?

 

[Jirwin]

Had the temp set to 25 initially to clear the window then down to 21. At 25 the gauge was fine, at 21 I could feel it blowing hot and cold. The fluctauations didn't seem to match speed, at one point it dropped to 60 when i was stoped, other times when i was moving and occaisionally it would drop off while the clutch was in and revs off for a gear change but come back as soon as the throttle was back on

 

[Jirwin]

All sorted, easy job to do. Thanks for the help

 

[jonisginger]

Which was?? I need helpz0r.

 

[Jirwin]

It was the thermostat in the end. Nice and easy to change, got mine from GSF. Need the thermostat, a new rubber seal and some coolant to top it all back up with. Can take you some pictures to point it out if that will help as most of the ones on here are by 1.8 turbo people

 

[jonisginger]

yeah

 

[Jirwin]

Right mate, never done anything like this before. Hopefully it works and all assuming you have the 16v engine. Sorry if its a bit noddy and for pic quality, done with camera phone


FIRST MAKE SURE THE ENGINE IS COLD!!!



Follow the hose, shown with a blue line in photo, back between the engine and battery down to where it goes into the block. Roughly the red circle area.




This pic above shows it from slightly more above. You're interested in the hose I've shown with the red line, the rear one




Get your head right in there and you'll see something like above. Undo the clip ringed in red by squeezing the two tabs together and slide the hose off. You'll need something like molegrips or strong pliers as the clip is fairly tough. Be careful as coolant comes out. Try and secure the hose out the way so it doesn't spill more!




Undo the two bolts, one ringed in red and the other where the ring is but behind the pipe and pull the plastic piece gently out the way. Quickly (but not rushing) pull out the old therostat making a note of which way round it is, put the new one in (with the new seal) the same way round as the old one. Replace the plastic block and bolt it back in place. Slide the hose back on and clip in place (I make this bit sound easy, its the hardest part!!!)

Top up any coolant and run the engine for a while to bleed the system. This took me ages, had to rev the engine and leave the header tank cap off and hopefully problem solved! Keep an eye on your level for a while after just in case any more air is trapped in

 

[FishmanUK]

I had the erraric temperature gauge problem on my 1.8T for a week or so but it seems to have gone away. I am not one to believe in cars fixing themselves so is there any explanation for this ?

 

[Jirwin]

Dunno mate, maybe its on its way out and only shows itself under certain conditions until it goes completely?

I don't know about on your engine but its quite easy to do and i only paid £6 for the thermostat, £1 for seal and however much coolant top up was. Its worth the spend before looking at other more expensive stuff if it shows itself again.

Unfortunately I've now got another thread due to my car not starting from cold. It may only be a 1.6 but i love my Leon, however if this is the start of everything going wrong I may have to be looking elsewhere soon...

 

[FishmanUK]

I found this guide for doing it on an audi TT
http://forums.audiworld.com/tt/msgs/1304805.phtml

My car still has approved used car warranty but if I take it over there and it performs normally I cant imagine them wanting to replace it for nothing. It either needs to fix or break properly !

 

[Jirwin]

That looks fairly helpful, you haven't really got the access I had on mine, I can get my whole head in there! I guess I have found a positive side of the 1.6, loads of room in the engine bay.

Personally I'd change the seal, I work on aircraft and we always change o'rings like that, even if its only been in a few days. Only takes a little nip and it to end up in a different position and you have a leak

If you take it to them and tell them whats going on they may change it anyway rather than risk it causing more damage and a possible big warranty claim