Q: Idle issue

asked by on

Hey just had a quick question I have a 2002 Honda civic automatic 1.7L and so I had a question earlier regarding that when I turn it on it would kind of rumble so I seen a hairline crack in the exhaust manifold which i got patches up pretty nice but then it still was the same so I let the car idle and pulled out each ignition coil one by one and there's 4 altogether and so I pulled 3/4 and the Rpm went down as.it should right? And then one of them when I pulled out it didn't.make a difference in the Rpm so then I switched two ignition coil and the problem stayed in the same cylinder could that mean I have a bad spark plug that needs to be replaced?

My car has 290000 miles.
My car has an automatic transmission.

Cylinder misfiring can be caused by: Ignition coil, spark plug, fuel injector, or a wiring issue to the coil or injector. By moving the coil from the misfiring cylinder to another and the misfire staying with the original cylinder, you have basically eliminated the ignition coil. You can try the same thing with the spark plug before buying new ones. If again the misfire stays with the same cylinder, then you have a faulty injector or signal/wiring issue to that coil or injector. Also, mechanical damage with that cylinder such as a damaged valve or valve seat can also cause a misfire. If you need further assistance with your misfiring issue, a certified technician from YourMechanic would be pleased to come out and help you figure out what is going on.

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

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: 97 Civic Ex AT- there is a delay in shifting when stopped at a stop light. It gets stuck between 10 to 15 miles

Hi there. What you are describing is typically an indication of a slipping transmission. In most cases the actual problem is the efficient flow of transmission fluid through the hydraulic lines of the transmission. Sometimes the simple act of having...

Q: Rough idling when cold, would not idle when it warms up

Hello. It sounds like you have already changed a lot of parts on this. Most of the time, the issue is actually caused by a leaking intake manifold gasket. This is the most common issue on this vehicle. It leaks...

Q: Cylinder 7 misfire in Ford F-150

A misfire code is a very common fault on your 2002 Ford F-150. The first step is to determine what the root cause is, from there it can be determined what needs to be replaced. Common causes are the spark...

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...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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.