Temperature Gauge Dropping Under Hard Acceleration
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
Temperature Gauge Dropping Under Hard Acceleration
Hi everybody, longtime lurker. I’ve had my 2012 IS350 AWD for a year now. This has been a problem since I got it, and I’ve only started worrying about this now because my friend has the exact same car and his temp gauge never moves.
Sometimes when i floor my car, the temp needle will go from half to about a third. It comes back up to half right after though. Is this considered normal? It only happens the first few times I floor my car then it steadily stays at the half mark. I always give it optimal time to warm up, I’ve never had any work done on the cooling system, (don’t see any in the service records either) and the car only has 140k KM on it. Any idea what the problem could be? Thanks in advance!
Sometimes when i floor my car, the temp needle will go from half to about a third. It comes back up to half right after though. Is this considered normal? It only happens the first few times I floor my car then it steadily stays at the half mark. I always give it optimal time to warm up, I’ve never had any work done on the cooling system, (don’t see any in the service records either) and the car only has 140k KM on it. Any idea what the problem could be? Thanks in advance!
Last edited by Tazclap; Feb 27, 2021 at 05:13 PM.
Intermediate
Joined: Feb 2011
Posts: 308
Likes: 100
From: CA
The only thing to really cause that would be an air bubble in the cooling system. That could be caused by the cooling system having had work done to it and it not properly bled afterwards. Also could be head gasket failure (not really likely on this engine), or a leak somewhere that's introducing air in the system.
Also possible someone had to pop open a hose to get to something else, the put the hose back, but didn't bleed it.
Check for leaks, crusty pink colored stuff around the front and back and under the engine. If none present, bleed it.
Also possible someone had to pop open a hose to get to something else, the put the hose back, but didn't bleed it.
Check for leaks, crusty pink colored stuff around the front and back and under the engine. If none present, bleed it.
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
The only thing to really cause that would be an air bubble in the cooling system. That could be caused by the cooling system having had work done to it and it not properly bled afterwards. Also could be head gasket failure (not really likely on this engine), or a leak somewhere that's introducing air in the system.
Also possible someone had to pop open a hose to get to something else, the put the hose back, but didn't bleed it.
Check for leaks, crusty pink colored stuff around the front and back and under the engine. If none present, bleed it.
Also possible someone had to pop open a hose to get to something else, the put the hose back, but didn't bleed it.
Check for leaks, crusty pink colored stuff around the front and back and under the engine. If none present, bleed it.
Will do, much appreciated! I sure as hell hope it’s not a head gasket failure
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
The only thing to really cause that would be an air bubble in the cooling system. That could be caused by the cooling system having had work done to it and it not properly bled afterwards. Also could be head gasket failure (not really likely on this engine), or a leak somewhere that's introducing air in the system.
Also possible someone had to pop open a hose to get to something else, the put the hose back, but didn't bleed it.
Check for leaks, crusty pink colored stuff around the front and back and under the engine. If none present, bleed it.
Also possible someone had to pop open a hose to get to something else, the put the hose back, but didn't bleed it.
Check for leaks, crusty pink colored stuff around the front and back and under the engine. If none present, bleed it.
You have a critter living in your engine bay, those black specks are clearly mouse droppings. I had some mice take up residence near my battery when COVID lockdowns first started and I was barely leaving my home. You'll want to hunt down wherever else they are before they become a nuisance and chew up your electrical system. Check around the battery area, your cabin air filter, etc. Set some traps. I took away their little nest they made and left some traps and some of that mint stuff around and they never came back into the car, though I did see them around for the first week but never caught one in the trap. It wasn't helping that I have a bird feeder so I had to stop putting in bird feed for a while to get them to go away.
Last edited by Zmon; Feb 27, 2021 at 08:29 PM.
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
You have a critter living in your engine bay, those black specks are clearly mouse droppings. I had some mice take up residence near my battery when COVID lockdowns first started and I was barely leaving my home. You'll want to hunt down wherever else they are before they become a nuisance and chew up your electrical system. Check around the battery area, your cabin air filter, etc. Set some traps. I took away their little nest they made and left some traps and some of that mint stuff around and they never came back into the car, though I did see them around for the first week but never caught one in the trap. It wasn't helping that I have a bird feeder so I had to stop putting in bird feed for a while to get them to go away.
Do you think they just made that nest? Otherwise the engine would have burnt it i’d think. Haven’t been driving much so my cars been sitting in the garage for a good week now.
damn I didn’t even notice that mouse ****, good catch. I guess that was their nest. One problem after the next :/
Do you think they just made that nest? Otherwise the engine would have burnt it i’d think. Haven’t been driving much so my cars been sitting in the garage for a good week now.
Do you think they just made that nest? Otherwise the engine would have burnt it i’d think. Haven’t been driving much so my cars been sitting in the garage for a good week now.
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Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
I would imagine within the last week or so it was made. That's probably insulation from various foam pieces in the engine bay so it wouldn't have burnt up. Remove the nest, clean the area of the droppings/urine (make sure you're washing your hands if you're doing this without gloves). I'm personally not a fan of putting down mouse poison simply because they can crawl up somewhere hard to get to and die, so I wouldn't recommend leaving any. They tend to make nests in warm places, and if you're up in Ontario, I imagine that warm engine area is nice and cozy compared to the outdoor weather.
i am indeed in Ontario. I got rid of their nest. Cleaned the droppings out of the engine bay and set 5 mouse traps in the garage. Appreciate the help!
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Yep, mouse nest. A friend of mine years back had a cat that would crawl up into the engine bay and sleep. One day he was driving and he heard a bunch of meowing, stopped the car and lifted the hood and behold, the scaredest cat you've ever seen. Not sure how it survived that ordeal being near the belt pulley area, but maybe it gave up some of its lives
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
Yep, mouse nest. A friend of mine years back had a cat that would crawl up into the engine bay and sleep. One day he was driving and he heard a bunch of meowing, stopped the car and lifted the hood and behold, the scaredest cat you've ever seen. Not sure how it survived that ordeal being near the belt pulley area, but maybe it gave up some of its lives
Lexus Champion
Joined: Oct 2019
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Likes: 3,672
From: California
True, but it could've been a bloody mess under there had the cat not held on for dear life and kept in its place and tried to run. But I've read plenty of threads where rats and mice got into the engine, so you are right. It would probably take you months to find wiring problems created by rats and mice...
A good tip is to give your hood a tap, especially in the mornings. If there's an animal in there, they'll typically leave. Better that than cleaning up a bloody mess/cleaning up someone's poor pet.
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
I think I’ve taken care of the mouse issue. Regarding the temperature gauge, I’ve taken my car to two different mechanics now and they assure me there’s nothing wrong with it. So I’m not really sure what to do. Perhaps I’m just overthinking it? The gauge only drops when I’m going full throttle for a good 10 seconds, and I’ve seen a few videos on YouTube of these cars doing 0-60 runs and their gauges do the exact same thing, however some don’t. So maybe my temperature gauge is just more sensitive? I’ve got no idea.
I think I’ve taken care of the mouse issue. Regarding the temperature gauge, I’ve taken my car to two different mechanics now and they assure me there’s nothing wrong with it. So I’m not really sure what to do. Perhaps I’m just overthinking it? The gauge only drops when I’m going full throttle for a good 10 seconds, and I’ve seen a few videos on YouTube of these cars doing 0-60 runs and their gauges do the exact same thing, however some don’t. So maybe my temperature gauge is just more sensitive? I’ve got no idea.
Possible 3 things sticking open thermostat, messed up temp sensor, or air in the system.
Getting a Lisle funnel would make it a breeze to bleed the coolant system. Then go from there.
Thread Starter
Driver School Candidate
Joined: Feb 2021
Posts: 15
Likes: 3
From: Ontario
Possible 3 things sticking open thermostat, messed up temp sensor, or air in the system.
Getting a Lisle funnel would make it a breeze to bleed the coolant system. Then go from there.
https://youtu.be/zUpXgAJ1gjU
Getting a Lisle funnel would make it a breeze to bleed the coolant system. Then go from there.
https://youtu.be/zUpXgAJ1gjU