Q: CEL on after spark plugs replaced

asked by on October 06, 2016

I was notified that I had a valve gasket cover leak, as my car was severely leaking oil. I had this replaced as well as the spark plugs replaced. This is been about 5 days ago. I was told to add some engine treatment, which I did. Now the car jumps badly when I reach about 20 mph, after that the jumping stops. Also, the check engine light is on, which it was NOT before. My anatomy knowledge of my car is extremely limited. Also, there is a rough idle. Where do I begin?

My car has 158000 miles.
My car has an automatic transmission.

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The first task is to find out what problem code is causing the Check Engine light to come on. Most auto parts stores will plug in a code reader for free (on a time-available basis) and tell you what code(s) are set.

The leaking valve cover gasket will have allowed oil to get onto the old plugs and plug wires, possibly damaging the spark plug wire boots. This is likely causing the misfiring you notice at lower speeds.

I would recommend having YourMechanic diagnose this issue, provide an accurate assessment of damage, and estimate the cost of repairs. One of our mobile and professional mechanic can come to your location for the diagnosis of your Check Engine Light and repair your vehicle as necessary.

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