strange missfire/stutter

151,000 MILES
Avatar
DWSG01
  • MEMBER
  • 2 POSTS
Hello I have an X reg Ford fiesta 1.25 Zetec. 2 days ago it developed a missfire when accelerating and also sounds like it has a small backfire occasionaly. 2 weeks ago it had a quick service new sparks new oil and filter and new air filter, I dont think the sparks or the HT leads are the problem as it has new HTs and new sparks and also when I take one HT lead off at a time the engine runs a lot rougher. I have checked as many sensors and cables as I can get to as I believed it could be the MAF sensor
, ICV etc. Out of the sensors I could get to, I was not sure what was what because haynes wasn't as helpful as it usualy is and am not sure if this model even has a MAF sensor as I have seen a few posts saying the zetec engine with the airfilter box on top of the engine block doesn't have one, I have ran injector cleaner through, put in different petrol to make sure it wasn't a bad batch and am now at a loss advise please anyone
Jun 3, 2012 at 9:58 AM
Advertisement
Avatar
ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
missfires come from low compression, bad plug or wire or coil, bad injector or a vacuum leak.
start with a compression test.

Roy
Jun 3, 2012 at 10:01 AM
Avatar
DWSG01
  • MEMBER
  • 2 POSTS
Thanks I think I can get hold of a compression testing kit so that will be then next thing I do if the compression is ok Im going for the ignition coil
Jun 3, 2012 at 10:22 AM
Add a reply
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.

Frequently Asked Problems for This Vehicle