Running rough


#1

i have a 1998 mazda mpv gave it a tune up … a week or two later it stared stalling, exhaust smells bad, it idles up and down… checked spark plugs, wires and distributor cap all look good… got the code 300 which is random misfiring, what do i do now?


#2

Two things I can think of off hand,
1 Try oem plugs gapped to the proper specs.
2 Plug wires can be very sensitive to being bent or mishandled, if you have not handled them with care they may need to be replaced.


#3

I had the same problem with my Silverado - the injectors needed cleaning.


#4

I would add that there are times when the wires end up on the wrong plugs.