Q: Car wont start unless I let it sit for 35 mins

asked by on November 30, 2016

After I drive my jeep maybe about 5 to 10 miles, I can turn it off and it won't start back up until it sits for 35 minutes. And it'll start uo amd run normal. I've been told it's common for the pcm to go bad on these models. I have the wj 4.8l v8 engine

My car has 178000 miles.
My car has an automatic transmission.

Ignition Coil Replacement $132.12 - $587.62 Get a Quote

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 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 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. 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.

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