Q: #7 misfire on my 2002 Dodge Ram 1500 4.7 replaced with new spark plugs nd replaced coil still getting error

asked by on

Replaced my lower radiator hoselower radiator hose,After that I started getting a #7 misfireWhen ahead and replace that spark plug along with my coil’s and it still coming up as a number seven misfire and my truck now has, no acceleration it doesn’t run as smooth as it used to it runs rough and it smells like gas at times because I have a hard time starting and also smells like radiator fluid

My car has 134000 miles.
My car has an automatic transmission.

Check compression in that cylinder to rule out a mechanical issue such as stuck valves or very low compression. Another possibility is a vacuum leak around the intake to that one cylinder. If so, that can cause a misfire. If the lobes on the camshaft are worn, that can cause a misfire and other inefficiencies as well. I would first check for a vacuum leak. If no leak, secondary firing patterns on the misfiring cylinder should be examined on an oscilloscope. The waveform will help narrow the potential causes to fuel versus ignition. Another possibility is the misfire is due to intermittent faults in the injector and/or ignition components so although these components appear to be in spec during static testing, in fact they are not reliable and are later, in service, operating intermittently. Finally, the ignition and fuel driver circuits in the PCM for the misfiring cylinder could be faulty; that is the absolute last thing to test though unless you happen to have handy a known good PCM that you can substitute. If none of these possibilities pan out, you can request a misfiring diagnostic and the responding certified mechanic will get this resolved. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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. #7 misfire on my 2002 Dodge Ram 1500 4.7 replaced with new spark plugs nd replaced coil still getting error

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: Q: Is it a fuel pump issue?

It's possible that a failing fuel pump, or a clogged fuel filter or fuel injectors for that matter, can cause stalling at idle but there are other common causes such as vacuum leaks, EGR system faults, sensor faults such as...

Q: Does the Dodge Caliber have an idle air control valve? I can't find a part matching its description

Hi, thanks for writing in. Your vehicle does not have an idle control valve and only has an electronic throttle control valve. You may have some dirty throttle plates. If you would like help, consider having an expert automotive technician...

Q: Q: Car will start but wont move

Hi There, It sounds like your car may be low on transmission fluid. Since automatic transmissions use pressurized hydraulic fluid to change gears, every time a gear change is required, the car's computer activates a transmission solenoid, which directs transmission...

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...
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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...