Skip the auto shop - Our mechanics make house calls

Q: Truck runs rough in 80 to 90 degree weather

asked by on

my truck starts fine gos into a high idile they kicks down in to a normal one after that when it gets to temp and the themastat opens the gauge drops to where it runs and then it starts running rough when the weather is 70 to 90 degrees out you step down on it somtimes it gets a little better and somtines it dont hope you have a idea tried of throwing new parts at it

My car has 215000 miles.
My car has an automatic transmission.

A: With the age of your vehicle, there are lik...

With the age of your vehicle, there are likely a few things that need to be maintained. All of the recommendations about to be made depend on what other repairs have been made recently. Since the issues are related to the ambient air temperature, you will want to start by checking your cooling system. The water pump and thermostat are two critical components that do age and will need to be replaced eventually. To test the water pump: feel the upper radiator hose while running (carefully, it will be warm), if you feel a good amount of coolant inside then the pump is functioning well. If it feels empty or like there is bad circulation, you will want to replace the pump.

You will want to make sure your coolant is topped off and in good condition. Another easy step to take is to flush the radiator. You will have to remove it and use whatever means you have to flush clean water through it. There are some mild solvents that will help to clear any coolant buildup inside. If you would like an expert to take care of this, a qualified professional from YourMechanic can come to your car's location to inspect the rough idle and pinpoint needed repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Engine doesn't wanna warm up

You should have the vehicle checked to see if the engine is not running hot enough or the coolant sensor is not reading the correct temperature causing an incorrect gauge reading from the engine actual temperature. If you have already...

Q: Brakes squealing

This circumstance is not unusual and I suspect is often related to the use of non-OEM rotors and brake pads and also the failure to re-apply factory specified shims and/or appropriate anti-squeal compounds and lubricants. Unfortunately, once non-OEM parts and...

Q: Not starting distributor spark

Hi there. You need to see if the distributor is turning when the engine is cranking. If not, then the vehicle has a broken timing belt. I would usually check the timing belt to see if it is intact. If...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...