Skip the auto shop - Our mechanics make house calls

Q: Missfiring engine

asked by on

The ECM is not functioning properly, the cylinders 4,5 and 6 have been malfunctioning.

Check on the misfiring, constant flow from EUI 4,5,6. Test EUI and was noted to be ok, swap EUI from 2,3 and no change was noted.

Hello. Knowing the you have a good fuel supply to the engine is a great start. Have you looked into you spark plugs and ignition system? Start by testing for a good spark at all plugs. This will test the coil and the wires. If needed, replace all plugs and wires at the same time (rather than one or two of them). This keeps wear on the engine consistent, and can make future repairs easier to diagnose. Catalytic converters and oxygen sensors can also play a large role in the engine performance. These can be tested with a good scan tool, or with a multimeter. The ECM may be trying to compensate for another issue with the vehicle. The only way to tell is to do some further testing.

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: Honda N WGN 660 5cc japanese frequent limp home mode

Hello, thanks for writing in about your Honda N WGN. A likely possibility related to the misfiring may be that the car's computer may have tried to recalibrate the fuel supply as a result of the faulty throttle control relay...

Q: Apparent timing chain failure.

Hello there, timing chains in most cases last a long time on your 2003 Ford Mustang. The fuel line repair should not have had anything to do with the timing chain issue. In cases where a timing chain is suspected...

Q: Why does my car vibrate so much when I am at a complete stop

There are many possible causes for this symptom; there could be a vacuum leak, or the car may simply need a tune-up. It would probably be best to have a certified mechanic take a look at the car and perform...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
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...
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.