Q: Car sputters and has weak power after new spark plugs and ignition coil were recently replaced

asked by on

Several months back my car was experiencing sputtering, weak acceleration (in the lower gears) and poor power and undesirable fuel economy. So I replaced the spark plugs and this helped for a few months and then recently the issue cropped again so I replaced the ignition coil and this helped marginally, the sputtering isn't as bad but there's still a lack of power and good normal acceleration. I'm curious if there's another issue outside of the ignition and spark plug system that could be causing this symptom. Thanks!

My car has 200000 miles.
My car has a manual transmission.

There are actually several possible causes for the engine to sputter. It is possible for there to be a vacuum leak, a faulty oxygen sensor, a catalytic converter that is starting to show signs of failure, or even a possible problem in the fuel system. It will be necessary to do some further diagnostics to determine which system is causing the problem, and then figure out which part in that system is the root cause. For example, if it is found that there is low fuel pressure in the system, it will then be necessary to figure out if there is a weak fuel pump, clogged fuel filter, or something going on with an injector. If the problem appears to be with the ignition, there could be a problem with a spark plug, ignition coil, ignition control module, or a fault in the wiring. I understand you said that the plugs and coil had been replaced, but it is possible that one of them have failed again, since the problem is recurring. If this is something you could use a hand in identifying, I would suggest consulting a certified mechanic, like those available at YourMechanic.com.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Car sputters and has weak power after new spark plugs and ignition coil were recently replaced

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: My car starts in the morning with a sputter.

The noise could be either an ignition coil misfiring and causing the engine to stall on a cylinder making the engine sputter or the engine is sputtering with an injector that is sticking until it get hot as it maybe...

Q: The headlights wont shut off and the horn keep honking when I turn them on.

It sounds like you have a rubbed through wiring harness or two. All the components you mentioned are switched on the ground side. That means if there is a short to ground on the switch side before the relay, then...

Q: Q: Why does the check engine light comes on and off

Generally, the check engine light comes on when something fairly serious is going on with the vehicle. This can happen for many different reasons such as a faulty mass air flow sensor, a faulty O2 sensor, a bad catalytic converter,...

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...
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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...