Code P0302, no spark cylinder number three

Tiny
DAPITAN2003
  • MEMBER
  • 2014 MINI COUNTRYMAN
  • 1.6L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 50,000 MILES
The Trouble Code is P0302, misfire in cylinder no. 2. I erased the code and I swap coils from cylinder number 2 to cylinder number one 1 and the code did not follow. I checked the sparks and there is non. I checked the ground wire (black color) and there is a good ground. There is a blue wire which is common on all 4 cylinders and another blue wire which I think is the signal wire. I was able to check the continuity of that signal wire from the computer to the connector and there’s a good continuity. I clipped my test light to the negative side of the battery, backed probe the two Blue colored wires, started the engine and check for signals and there is signals. I wonder why there is no spark, any thoughts?
Sunday, January 30th, 2022 AT 8:42 AM

5 Replies

Tiny
STEVE W.
  • MECHANIC
  • 14,522 POSTS
Okay, looking at the wiring diagram I see a black wire that grounds all 4 coils, a green wire that feeds power to the coils and for cylinder 2 a blue wire which is the trigger wire from the DME To test it I would erase the code then use the test light connected to a good ground to test the connection for coil 4 which is the orange wire on pin 17 next to the blue wire for coil 2 do you see the ignition control pulses? If yes, probe the blue wire for coil 2 on pin 16 and see if there are pulses there. If you see them there, check at both coils. If you see pulses there, then pull the coil up and use the test light probe to see if there is spark at the coil. Then pull the plugs and verify if you have spark or not. If the signal is there but no spark, then it's possibly the connector itself that's bad. If you swapped the coils with no change then it likely isn't the coil. However, if the code is still there it may turn off the coil if it is shorted or pulling excess current.
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
+1
Sunday, January 30th, 2022 AT 12:37 PM
Tiny
DAPITAN2003
  • MEMBER
  • 3 POSTS
Thanks Steve, I checked the voltage going into cylinder no. 2 with a voltmeter, the green wire which feeds power and the blue wire which is the trigger wire like you said and both wires showing 14 volts while the engine is running. The same thing happening on cylinder no. 4. BTW I erased the code before doing this test. I am thinking the ignition coil connector on cylinder no. 2 is causing this problem.
Was this
answer
helpful?
Yes
No
Monday, January 31st, 2022 AT 7:54 PM
Tiny
STEVE W.
  • MECHANIC
  • 14,522 POSTS
If both wires are showing a constant voltage that is the problem. The trigger wire should be rapidly switching on and off to trigger the coil. Use a test light to compare it to one of the other working cylinders, the reason being that a typical meter doesn't respond fast enough to read the voltage changes, so you get a false number. If you don't see the control pulse it could be the driver transistor in the PCM has shorted.
Was this
answer
helpful?
Yes
No
Tuesday, February 1st, 2022 AT 4:23 AM
Tiny
DAPITAN2003
  • MEMBER
  • 3 POSTS
Thanks again Steve, I back probe all four trigger wires with test leads and use my test light to check for pulses. It looks to me that all four have the same rate of pulse.
Was this
answer
helpful?
Yes
No
Friday, February 4th, 2022 AT 6:13 PM
Tiny
STEVE W.
  • MECHANIC
  • 14,522 POSTS
So, it all checks out but no spark, is that using a spark plug or a tester? You swapped the coils, what about the plugs? Could be a bad one even if it's new.
Was this
answer
helpful?
Yes
No
Friday, February 4th, 2022 AT 9:18 PM

Please login or register to post a reply.