Quote:
Originally Posted by Jimbo370
I am having the same problem. code PO900 THE MULTIPLE MISFIRES. I changed to HFC when it started and a light pulley.Then changed full agency exhaust and K&N drops and my mechanic keeps erasing the code. Now I added the exhaust extenders and it threw the same code in 40 degrees 2 days later. Changed spark plugs at 93k and wondering if its the COIL PACK. # 5 HAS 3 MISFIRES.  FOLLOWING |
Switch the coil pack with one of the other cylinders and see if the code follows it.