Coolant Temperature Gauge rising to 95º and then back to 90º

[Turbo_Boss]

Hello Guys,

I have a 2002 Skoda Octavia 1.8T with only 56,000 kilometers ( I just use it to go from home to my work and them back to home)

I have a small problem with my coolant temperature.

Both Coolant fans are working in slow and fast speed
AC is working OK and is cooling perfectly
Fuse over battery are OK and not melted

When I am at stop light the coolant temperature rise a little bit from 90º to 95º (Please check the photo) It does not rise more than that.

When I begin to drive, the coolant temperature go back to the middle (90º)

Also, one day that I saw the temperature in 95º, I turn off the engine, wait a little and then start again the engine........ The temperature goes to 100º and a few sec later go back to 90º

I was thinking the Termo Switch was not working but I open the hood and I see both fans are working in hi speed and then they cycle to slow speed.

This problem happened after I took the car a weeks ago to the VW Dealer to fix a small leak on a coolant hose 1J0 122 109AQ that is near the coolant reservoir and when they gave me back the car, I notice they put me in a bag the damage hose part + two empty G12++ Coolant 32onz bottles.

I was curious because I am pretty sure when the replace that small hose some of the coolant loss on the floor and they need to add more but I was think that maybe one bottle plus water was enough...............So when I ask the mechanic guy, he says he put the 2 bottles and they do not mixed it with water and that this is OK

Here in my country the weather is very hot. I know the G12++ Coolant has to be mixed 50/50..............Can this be my problem that the coolant temperature rise a little........ Or this can be a symptom of a water pump that the plastic impeller is going to fail

THX

Isaac

[bigdave260]

I'm no mechanic but straight coolant is going to be better than water. Pretty warm here in Australia mate and they chug along just fine.

Possibly an air bubble if the change in temp is very quick?

[BlackSuperb]

I drove my TDI around at 42 degrees outside air temp for a week or so last summer and the coolant temp was spot on 90 degrees in traffic or on the highway.

[Brycem]

Try posting same post on the briskoda forum as they have many more members and a dedicated mark 1 octavia forum. Mk 1 octavia was never sold in Australia.

[Turbo_Boss]

I took the car to the dealer and they check all and toll me that the problem is the water pump. Since they want to charge me $280.00 for a new water pump with plastic impeller and 150.00 for hand labor. I tell them that I don't have money to fix it right know, that I will take the car to them in January. The guy toll me that they will remove the thermostat and leave the the engine without it to help the engine not overheat. I have the thermostat with me and I bring the car home and the temperature was always on 90º

I just order a complete timing belt kit with water pump with steel impeller for $259.00

So back at home, I open the hood and notice that they move a bracket were the accelerator cable goes and they leave it like you see in the pic. I really don't understand what was they checking in that hose........Do that hose has something to do with the coolant temperature?

I am curious, what that hose do? (Red Arrow) Why they move that part?



THX

[gldgti]

Hey mate,

Unfortunately your octavia is different to all the octavia's in australia - so for specific help with your engine you'd be better off to ask in the polo section or mk4 golf section - those cars came with the 1.8T in australia. Here, we only have the 1Z octavia, no 1U

That hose in your picture looks like vacuum supply line for the brake booster etc. The little plastic round thing looks like a one way valve.

Show us a pic of your 1U octavia!

[Idle]

I took the car to the dealer and they check all and toll me that the problem is the water pump. Since they want to charge me $280.00 for a new water pump with plastic impeller and 150.00 for hand labor. I tell them that I don't have money to fix it right know, that I will take the car to them in January. The guy toll me that they will remove the thermostat and leave the the engine without it to help the engine not overheat. I have the thermostat with me and I bring the car home and the temperature was always on 90º

I just order a complete timing belt kit with water pump with steel impeller for $259.00

THX

From experience with other vehicles, I'd suggest that the temperature rising above the set maximum and then dropping back is a sticking thermostat — when you fit the new water pump, I suggest you replace the thermostat as well. Put the old one in a container of water and bring it to the boil, you'll probably see it open quite suddenly or stick partly open.

Running without one long-term is not good for your motor, it slows the warm-up time (that's what the thermostat is there for — to reduce the time the engine spends running cold and wearing fast.)

Incidentally, unless you are in a very cold environment and need the anti-freeze properties, your engine will cool better with the recommended coolant/water mix than with straight coolant.

Plain water cools better than most coolant additives, which are there for reasons other than cooling efficiency.

[Turbo_Boss]

Hey Guys,

Just to let you know that the problem was my Water Pump. As you can see on the attached pics, the factory water pump has a plastic impeller that with the time the plastic get brittle and then it cracks

My car is a 2002 with only 55,000 kms.

I took the opportunity to install a timing kit, GEBA water pump with steel impeller, new thermostat and new G-12++ Coolant

Isaac