Curious about Cooling behaviour
Forum rules
Many subjects will have been discussed before. Please try the search function before starting a new thread.
Check in the Know Your 2 as the information you need may already be there.
Important ! - Please make your topic title as descriptive as possible . titles with just "help" generally dont get as many answers as a title that points to the problem
Many subjects will have been discussed before. Please try the search function before starting a new thread.
Check in the Know Your 2 as the information you need may already be there.
Important ! - Please make your topic title as descriptive as possible . titles with just "help" generally dont get as many answers as a title that points to the problem
-
Topic author - Posts: 127
- Joined: 18/09/15 9:42
- Years of MR2 Ownership: 4
- MR2's Owned: 1
- Real Name: Don
- Gender: Male
- Location: Chelmsford, Essex
- Has thanked: 1 time
- Been thanked: 3 times
Curious about Cooling behaviour
Right:
Mk2 Rev 2 N/A.
From stone cold, it takes a little while (3-4 minutes) for the temp gauge to get moving.
It then sits steady as a rock with the needle just in line with the thermometer bulb on the guage all day long.
Until...I get stuck in a long stationary queue. Whilst it's sitting there, guage stays put, but...when we get going again, it drops right down to cold and then comes back up again after a couple of minutes.
I'm not concerned about it as such,as it seems to sort itself, would just like views on why it does that, does it indicate a thermostat issue? Coolant level looks OK.
Mk2 Rev 2 N/A.
From stone cold, it takes a little while (3-4 minutes) for the temp gauge to get moving.
It then sits steady as a rock with the needle just in line with the thermometer bulb on the guage all day long.
Until...I get stuck in a long stationary queue. Whilst it's sitting there, guage stays put, but...when we get going again, it drops right down to cold and then comes back up again after a couple of minutes.
I'm not concerned about it as such,as it seems to sort itself, would just like views on why it does that, does it indicate a thermostat issue? Coolant level looks OK.
-
- Posts: 1029
- Joined: 31/07/09 7:36
- Years of MR2 Ownership: 8
- MR2's Owned: 3
- Real Name: Mark
- Gender: Male
-
Topic author - Posts: 127
- Joined: 18/09/15 9:42
- Years of MR2 Ownership: 4
- MR2's Owned: 1
- Real Name: Don
- Gender: Male
- Location: Chelmsford, Essex
- Has thanked: 1 time
- Been thanked: 3 times
Re: Curious about Cooling behaviour
Coolant and thermostat not changed in last three years since I've had it, don't know about before then.
-
- Posts: 2558
- Joined: 14/05/04 1:00
- Years of MR2 Ownership: 9
- MR2's Owned: 3
- Location: North Kent
Re: Curious about Cooling behaviour
likely theromstat.
once warm, the needle should remain a little under half way on the gauge is ALL conditions. Shouldnt budge.
once warm, the needle should remain a little under half way on the gauge is ALL conditions. Shouldnt budge.
-
- Posts: 1474
- Joined: 20/04/11 23:18
- Current Model: None
- Years of MR2 Ownership: 23
- MR2's Owned: 1
- Real Name: 2023 i30N Hatch 6MT
- Gender: Male
- Location: Tauranga >>> New Zealand
- Been thanked: 1 time
- Contact:
Re: Curious about Cooling behaviour
I agree with others here, its sounds like the thermostat getting "Stuck" open.
The temperature sender for the gauge is worth a check. I had to replace mine way back because the male spade connection terminal on it was loose. Its been fine now for like 20 years.
The temperature sender for the gauge is worth a check. I had to replace mine way back because the male spade connection terminal on it was loose. Its been fine now for like 20 years.
Re: Curious about Cooling behaviour
I would say thermostat or water pump (less likely).
Of course start with thermostat as is cheap as chips or even try to bleed the system first. It might be an air blocked.
Water pump is lets say rev related as is driven by the motor. The higher rev the faster water flows so when you are stopping the water flow is limited. When you rev it water manage to go through as there is more pressure through the stat so most likely your stat is busted.
Of course start with thermostat as is cheap as chips or even try to bleed the system first. It might be an air blocked.
Water pump is lets say rev related as is driven by the motor. The higher rev the faster water flows so when you are stopping the water flow is limited. When you rev it water manage to go through as there is more pressure through the stat so most likely your stat is busted.
-
- Posts: 1474
- Joined: 20/04/11 23:18
- Current Model: None
- Years of MR2 Ownership: 23
- MR2's Owned: 1
- Real Name: 2023 i30N Hatch 6MT
- Gender: Male
- Location: Tauranga >>> New Zealand
- Been thanked: 1 time
- Contact:
Re: Curious about Cooling behaviour
How clean is your coolant ? if the system has not been running antifreeze rust inhibitor it will be a mess with possible blockages. If its really clean just swap out the Thermostat. Get a genuine Toyota one, its very well made the aftermarket ones are crap. Bit of a pain to change its on the front drivers side of the car engine but its much easier to get to with the A/C pulled out of the car.