Hi,

I have a 2004 Acura TL and I got a misfire in cylinder 4 , the other cylinders don’t have any misfires. I recently replaced all spark plugs, both valve cover gaskets gaskets, air filter, cleaned throttle body, cleaning fuel injector with seafoam .

I tried swapping ignition coil from cylinder 4 to 5, but cylinder 4 is still misfiring.

I found out that the ignition coil connector from cylinder 4 did not fully snap on the ignition coil and I replaced the ignition coil connector plug. It is still misfiring. I checked with a power probe if the connector works, which it did.
The connector was an aftermarket piece. I looked at the connectors from cylinder 5 and 6 which have tiny numbers on the blue part of the connector. My assumption is that the connector I bought has not the same numbers as the original connector from cylinder 4?

Any help will be really appreciated, thank you!!

 

Try a different spark plug.

 

Also switched spark plug with cylinder 5 and still misfiring

 

If the plug, wires and coil are working correctly, all that's left is the computer. Is the car throwing any codes?

 

That is also what I thought, perhaps the timing of the spark is incorrect for cylinder 4?
I scanned the car while running and I got the following codes back;

B1060 Relay Control Module Lost Communication with Gauge Control Module (VPS/NE Message)
B1061 Relay Control Module Lost Communication with Gauge Control Module (A/T Message)
P0304 Cylinder 4 Misfire Detected
P0154 HO2S(A/F sensor) B2 S1 no activity

 

Did you check the ignition coil with a spark tester?

Could be a bad injector.