Q: When the car is driven and parked, it takes about 2hours to restart it.

asked by on

My car is a 2005 Hyundai Santa Fe and normally drives well. Over the past few months, whenever the car is driven and parked, it doesn't start until after 2 or more hours. The fuel pump has been changed but the problem still persists. My mechanic wants to change the engine coolant temperature sensor but he is not sure if it's the problem. He conducted a diagnostic test but said the result showed nothing specific. What could possibly be the cause?

My car has 122000 miles.
My car has a manual 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. Other 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 cycling problem which can be very difficult to trace. 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 1,000 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!
  1. Home
  2. Questions
  3. When the car is driven and parked, it takes about 2hours to restart it.

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: On the radiator cap there is light brown pudding/paste deposit.

Hello Daniel, thank you for writing in. While these issues are frustrating, it may be as simple as needing to flush the system. Yes when you flush the entire system, you should be able to flush the water pockets as...

Q: Dealer put an "old battery" in my car, and now I'm having all sorts of problems.

Advising you is hard because consumer rights vary somewhat from state to state (I don't know what state you are in). If you were in Ohio and they did what you are describing, the dealer would have significant "problems" both...

Q: How long will a car with 180000

Hi there. It really depends on how well the vehicle was maintained before you purchased the vehicle, how it was driven and how well you keep up with recommended service and maintenance that will indicate how long the vehicle will...

Related articles

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...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.