Alright so my car ('00) was missing every now and then and I got the standard engine miss code, P1420 maybe, dont remember exactly. When I saw that I ordered 6 new coils and put them in on Sunday. Today I noticed a slight miss again while i was backing up. Also, I replaced the spark plugs with NGK platinum (or whatever the expensive ones are) a year and a half ago. Does anyone have any thoughts?

 

btw.......another code has NOT shown up yet

 

O2 sensor?
Fuel system?

 

I was thinking bad fuel, but it's missing in reverse. Maybe recheck the gap in the plugs and reset the computer.

 

Have you installed a new MAF at any point? Keep the MAF in mind.

 

MAF is the defaut culprit for all performance problems.. lol

 

ill look into possibly getting a maf in a few months but for now i think i am going to check spark plug gaps. also note that after i installed the new coil packs it was not missing as much or as big of a miss as before. not sure if that might help in any diagnosis but wanted to throw it out there

 

A miss is a miss, reverse has ZERO impact.

As mentioned, MAF could be culprit, but typically doesnt cause misfire. I would check injectors as well. You may also want to elaborate on "miss" because often times people say its a miss when there is just stuttering or chatter.

EDIT/ADD: Dont delay on this, if you are truly missing due to spark you are POURING raw fuel over the catalyst, if you have a cali-spec this is especially bad. when i had misfires i waited because it was so intermitent, bad idea, front pre-cat went out.

 

replace the maf sensor next......