Q: Car overheating and not accelerating

asked by on January 28, 2016

I was told that the thermostat was not opening up causing the engine to have a muffled sound. This is sending a message that the car is overheating, even though it is not. It could need the temperature sending gauge replaced. In addition, the Engine and Transmission message continues to light up. The car also struggles to accelerate in drive. I've had two different diagnosis for the problem and need to figure what is going on so I can get it fixed.

Car is overheating Inspection $94.99 - $114.99 Get a Quote

As far as the thermostat causing the motor to sound muffled, I personally have never heard of such a thing. Your thermostat controls when the flow of coolant in your cooling system starts, allowing the coolant to flow and cycle through the radiator being cooled by the fans. This, in turn, cools the block and head through the coolant jackets. If the vehicle temperature is low the thermostat will stay closed not allowing the recirculation of coolant to occur in turn continuously heating the coolant up. To truly know whether or not the coolant temperature sensor is falsely increasing the temperature on the gauge or not an automotive scanner should be hooked up and the actual output coming from the powertrain control monitor that monitors the engine coolant temp can be viewed. The lack of acceleration could be caused from the vehicle actually overheating which could have lead to serious engine damage.

A proper cooling system diagnostic should be performed by a qualified technician. A diagnostic like this can show whether the system holds the correct system pressure, whether or not the fans operate, what the actual temperature of the engine is, and what memory fault codes stored in the powertrain module. The mechanic can survey all this information to pinpoint the cause of your overheating issue and come up with the right repair.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Damaged key chamber
Hi. It sounds like you need to replace the parts that were damaged during the theft attempt. On this vehicle, the exterior door handle must be removed to access and replace the door lock cylinder. A professional, such as one...
car slows with acceleration
The hesitation may be a dirty throttle body (https://www.yourmechanic.com/services/clean-throttle-body) or bad throttle position sensor (TPS) (https://www.yourmechanic.com/services/throttle-position-sensor-replacement). If it drives better with OD off, I suggest leaving it off or having it diagnosed and repaired. It won't hurt anything to leave...
I need help with diagnostic trouble codes that suddenly appeared making vehicle almost undriveable.
Firstly, you should have the battery disconnected and the PCM disconnected. Check their connectors for any problems and apply dielectric lube to the connectors so the connection is clean from corrosion. If the problem continues then replace the PCM. All...
Door ajar warning on, interior lights on - 2014 BMW X1
Hello. The body control module (BCM) controls the interior lights for this vehicle. The BCM gets inputs for the interior lights to come on by any one of the door switches or the interior light switch. If any one of...
My truck is overheating, I hear it hissing and I see steam too.
Hello, thanks for writing in. I'd be happy to help. Steam from the engine is usually a sign of a small cooling system leak (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-coolant-reservoir). I would recommend taking a close look at the area where the steam appears to...
So I recently left my 2010 Dodge Charger with out oil and it started a tapping noise inside the motor.
Hi there. When operating an engine without any oil in the oil sump (oil pan), then the bearings, rings, valves, and lifters will starve of lubrication and begin to tap and knock. The lifters were closed up causing the valves...
I broke down yesterday and the engine will crank and back fires but will not run 1993 Dodge Dakota
Hello. I would typically start by doing a compression test of the engine. If the compression is low then there is a timing chain issue. If the compression is fine then you may have an issue with the ignition timing...
Car won't start
Hi there. Although the voltage looks good on the battery, the unknown is the cold cranking amps; which is what is important asset of the battery for start up. If the AC was serviced yesterday, the battery cables would have...
the idle is a little rocky, but better since i put iridium plugs in it but it still didn't accelerate as soon as i press the gas
The backfiring and the rough idle are probably related. Backfiring (https://www.yourmechanic.com/article/what-causes-a-car-to-backfire) is often caused by a too lean or too rich air-to-fuel ratio although a few other causes are discussed below. A backfire in the intake manifold is caused by...

Related articles

Understanding Main Gears Vs. Planetary Gears
Aspiring Aspiring mechanics spend hours learning about how main gears and planetary gears work in a car transmission, so a full dissertation simply isn’t possible within this relatively brief article. If you’re curious about how they work, though, this brief...
Symptoms of a Bad or Failing Oil Cooler Adapter Gasket
Common signs include oil leaking from the oil cooler adapter, engine block, and oil filter. Prevent damage to your engine by getting the gasket fixed.
How to Replace a Transmission Position Sensor (Switch)
Transmission position sensors (TPS) switch ensures a car is in Neutral or Park when started and shuts the car down if it's not in the right gear.