99 Tacoma codes p0300 p0301 & p0304 & runs rough. Replace coil?

Hi all I have a 99 Tacoma Access Cab 4x4 SR5 with 137,000 miles that stated running very rough. The check engine light came on and blinks on & off while I drive. The codes are

P0300 - multiple misfire
p0301 - cylinder 1 misfire
P0304 - cylinder 4 misfire
P0171 - system too lean bank 1

I have replaced the plugs and wires and it didn't help at all. I believe cylinder 1 & 4 are both on the same coil pack so I am no suspecting the coil pack.

Questions

1. Am I correct to suspect the coil?
2. Is the code P0171 related to the misfires or is it a separate issue?
3. I don't know which side of the engine cylinders 1 & 4 are on. Can someone tell me or provide a diagram of the ignition system?

Thanks,
David

 

Without spending any money, clear the codes switch that coil pack out with a different cylinder and see if the new codes reflects the coil you switched. Then replace that one. To lean out a cylinder means to remove fuel so P0171 is O2 sensor problem not misfie issue.

firing order is 1,2,3,4,5,6
#1 is pass side front, #2 is driver side front

 

Or bad injector, which would also cause a misfire code.

 

did you ever solve it? i’m experiencing the exact same thing.