Skip the auto shop - Our mechanics make house calls

Q: Rough idle and SEL is flashing. I've replaced all 6 plugs and coil packs. The car still has a rough idle and no power.

asked by on

Rough idle. Sel flashing. Had a friend stop by with his scan tool and check. Was told 2,4,5,and 6 not firing. Replaced all 6 spark plugs as well as all 6 coil packs. Still have rough idle, no power and sel flashing again.

My car has 107000 miles.
My car has an automatic transmission.

A: Misfiring can be caused by lack of spark or...

Misfiring can be caused by lack of spark or lack of fuel. If the same cylinders are still showing codes for misfiring after replacing the coils, the problem can lie elsewhere. If it is the coils not firing, there can be an issue with the wiring harness from the engine control unit to the engine harness. Also, the engine control unit itself can be bad, not sending signals to fire the cylinders. Also, lack of fuel can cause misfiring. Dirty, clogged, or failed injectors can be at fault. Also, a wiring or engine control unit fault can prevent injectors from firing as well.

To avoid any unnecessary repairs, have a certified technician, like one from YourMechanic, come to your location and diagnose the engine misfiring to isolate the exact cause.

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

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: What to do with wires from voltage reg

Try going to this forum and look at the wire diagrams in the forum. I hope this helps. I Google searched and tons of conversions are in there.

Q: Indicator stuck in drive on dash

Hi there. The issue you are experiencing is most likely the Park Neutral Position switch. A technician can come out and replace the switch to display the correct position on the dash.

Q: One of the wheels that holds the serpentine belt has completely snapped off, I believe it is the power steering one. repair cost?

Hi there. A picture is worth a thousand words. Assuming it is the power steering pulley that has broken would lead me to question why this happened. It could be the power steering pump has seized resulting in a broken...

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...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
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...