Skip the auto shop - Our mechanics make house calls

Q: Starts cold but shuts down when it gets up to normal temp

asked by on

Jeep will start when it's cold but shuts down and won't restart once it gets up to normal temps. It will turn over but acts like its not getting gas. I changed fuel filter, pump and relay

My car has 99000 miles.
My car has an automatic transmission.

Hi There, What you are describing sounds like an ignition coil pack that may be failing. Ignition coils are prone to this type of erratic functioning or heat cycling when they are beginning to fail due to the temperature fluctuations under the hood which ultimately cause them to shut down causing the car to only run after cooling down for 30-40 minutes. Ignition coils are coated with a varnish-like insulation that becomes brittle over time after being stretched then contracted repeatedly The insulation develops small fractures that open when heated and close when cooled. When open, they allow shorting of coil windings and decrease or eliminate the coil’s ability to function. This process will repeat itself continuously until the coil ultimately fails completely and must be replaced. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your ignition system.

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・Fair and transparent pricing

Get a quote

What others are asking

Q: My truck keeps dying

Hello and thank you for contacting YourMechanic. This sounds like an issue Check the wires to the starter and ignition switch. Look for any loose wires on the starter and starter relay. Look for any loose ground wires around the...

Q: Cylinder Deactivation System in Bank 1

The diagnosis and repair of this type of problem will require the work of a professional. The cause may be as simple as a low oil level or the need for an oil change or as complicated as the need...

Q: Smell coming from A/C vents

Hello there, a few different items can cause this type of smell in the vehicle. The most common is the heater core, but that has already been checked. Other likely causes would be an exhaust leak, fuel leak, or something...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.