Q: Stalling engine after engine warms up

asked by on

Truck will idle and run fine at times and when you least expect it , it will act funny and sometimes stall out completely

My car has 117450 miles.
My car has an automatic transmission.

This is a common sign of a faulty ignition coil. Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeated as the copper beneath them expands and contracts at a higher pace than the insulation. The insulation develops small cracks that open when heated and close when cooled. When open, they allow shorting of the coil materials and decrease the coil’s ability to function. This type of temperature cycling happens because every time you shut the engine off, the fan stops running, the coolant stops flowing and the temperature under the hood rises. Every time you start the engine again the coolant flows, the fans turn on, and the temperature drops. The areas in and around the tops of the combustion chambers, the exhaust manifolds, and the exhaust components are hundreds of degrees hotter than the outside temperature under the hood. When this heat dissipates and is absorbed under the hood, it is trapped causing this cycling effect. Components that contain heat sensitive materials include parts like coils, injectors, igniters, and some sensors. Any of these may be potentially subject to this same kind of heat problem which can be very difficult to trace. I would recommend having an expert from YourMechanic come to your location to take a look at your vehicle to properly diagnose your ignition system.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Stalling engine after engine warms up

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

Get a quote

What others are asking

Q: will a temperture switch cause an engine not to start?

The engine coolant temperature sensor sill not cause the engine to die or not start, but can cause the fuel system to go full rich. The engine dies when getting hot is most likely due to an ignition spark loss...

Q: Squeaking sound - 1990 Chevrolet K2500

Hi there. It sounds like it could be a harmonic balancer. Before replacing the balancer, check the radiator fan to see if the blades are hitting the shroud or anything else. Also check the fan clutch, if equipped, for...

Q: nissan d21 pickup 2.4ltr no 2 cylinder mot firing

Hi there. How did you determine that cylinder 2 is misfiring? Is there a check engine light on with a stored code? What is the code? Have you checked the compression on the other cylinders? A cylinder leak down test?...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...