Q: Misfire in number 4 cylinder

asked by on

I have replaced the number 4 injector. Rechecked the injector plug, but still have a miss code come up for the number 4 injector.

My car has 135445 miles.
My car has an automatic transmission.

Hello. Check to see if the code defines a "circuit" that is a wiring issue with No. 4. If it does, you have to look at the signal to the injector.

Using a mechanic’s stethoscope, it is easy to hear the characteristic clicking noise that should be present if you probe the injector body and compare the noise (if present) to that from adjacent known good injectors to see if your No. 4 is even operating. If not operating at all, check resistance across the two injector solenoid terminals and compare to FSM. Depending on the code, it is that possible there is a related "ignition" issue in that cylinder, too. Particularly since you are describing the symptom as a "miss."

If it is ignition-related, you could have a bad plug or plug wire for No. 4. If you replaced it with a "used" injector, by the way, it could easily be plugged. Injectors typically have replaceable internal filters and used ones should be cleaned ultrasonically on a professional cleaning machine. It is very economical, too. Typically around $17 each at the shops which are known to do exemplary work of this type. If you would like to have this looked at more thoroughly, a qualified technician from YourMechanic can come to your car’s location to inspect the code and perform any required repairs.

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. Misfire in number 4 cylinder

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: Stiff shifting when car sits

Hello. If the dealer is saying it is a normal condition, this does not mean it is a problem but only that the manufacture does not have a fix for the problem yet. If you put the vehicle in reverse...

Q: The engine has no power and shakes a lot

Hello. If the engine is shaking that bad and has no power, then it may have a bad misfire. This can be caused by a bad spark plug, but it can also be caused by a bad sensor such as...

Q: Q: Belt squealing

This is a pretty common problem for your vehicle. Your serpentine belts are likely worn out. In addition it is highly likely that you could have a bad pulley or belt tensioner. If any one of these things are a...

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...