Inconsistent Misfire

1. user_27192 Saxperience Addict Joined: Sep 2008 Suffolk Posts: 11590 ITB'd Saxo VTS & Mazda 6 MPS

   #1 2nd October 2011, 11:18

   Serviced the car last week - oil/filter/plugs
   
   Since then the car has decided to misfire at low revs (pulling away in 1st/2nd) and has a slightly shit idle. If Im in 2nd, it misfires up to about 2.5k revs and is fine.
   
   Ive changed the plugs for a second time and that hasn't done anything. Im thinking next step is to try another coilpack?
   
   But because its on/off Im just wondering if there's anything else, like a loose connection somewhere? We didn't touch anything that didn't need doing so fuck knows.
2. RustySkull Saxperience Post Whore Joined: Oct 2009 Basildon And Corringham, Essex Posts: 5179 MK1 Focus RS, Discovery TD5, Renault Trafic 2.0

   #2 2nd October 2011, 11:51

   Could be a coincidence and be the Coilpack, But make sure you have the leads on tightly if you have the old style
3. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #3 2nd October 2011, 12:06

   Does the misfire happen when the car is hot?As faulty coil packs show these symptons when hot.
4. user_27192 Saxperience Addict Joined: Sep 2008 Suffolk Posts: 11590 ITB'd Saxo VTS & Mazda 6 MPS

   #4 2nd October 2011, 12:13

   yeah does tend to be when the engine is warm/hot
5. user_27192 Saxperience Addict Joined: Sep 2008 Suffolk Posts: 11590 ITB'd Saxo VTS & Mazda 6 MPS

   #5 3rd October 2011, 20:22

   and now seems to also be when its cold
6. user_27192 Saxperience Addict Joined: Sep 2008 Suffolk Posts: 11590 ITB'd Saxo VTS & Mazda 6 MPS

   #6 3rd October 2011, 20:23

   is it worth changing to HT leads and and external coilpack?
7. user_16747 Banned Joined: Jul 2007 Posts: 4328

   #7 3rd October 2011, 20:29

   Does sound like either the coil pack or it has being known on other cars with a similair set up that one of the wires to the pack has being damagd.
8. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #8 3rd October 2011, 20:30

   Quote:

   Originally Posted by Chr15 is it worth changing to HT leads and and external coilpack?

   Not really mate I take it your saxo has the overhead in line coil pack? I`d just try another 1 of these mate.
9. Aaron Saxperience Post Whore Joined: Jan 2008 ..... Posts: 5231 ..............

   #9 3rd October 2011, 20:32

   Quote:

   Originally Posted by Chr15 is it worth changing to HT leads and and external coilpack?

   
   
   depends on how much you want to spend^^?
   
   try another coilpack, check spark plug gap?
   stick your old spark plugs in? see if that makes a difference?
   
   its process of elimination im afraid
10. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

    #10 3rd October 2011, 20:36

    You can get uprated coil packs but their not really worth it unless you`ve got a high spec engine car.
11. user_27192 Saxperience Addict Joined: Sep 2008 Suffolk Posts: 11590 ITB'd Saxo VTS & Mazda 6 MPS

    #11 3rd October 2011, 20:38

    Quote:

    Originally Posted by Aaron depends on how much you want to spend^^? try another coilpack, check spark plug gap? stick your old spark plugs in? see if that makes a difference? its process of elimination im afraid

    old and new plugs made no difference.
    
    wasnt sure if there'd be better reliability or any other pros in it
12. Aaron Saxperience Post Whore Joined: Jan 2008 ..... Posts: 5231 ..............

    #12 3rd October 2011, 20:49

    oh HT leads and external would be better yea, but for the pros & cons side of things.
    standard engine isnt worth it. a standard coilpack is more than up for the job(they dont fail that often.
    
    it might not even be your coilpack(one of them little springs in the end of the coilpack didnt fall out did it?(where it goes onto spark plug)?
    
    got a multimeter? check coilpack plug for power and what readings you getting?
    
    take coilpack off, put a spark plug in one of the arms and crank over( holding the coilpack with plug against/near a metal(& earth) object,not near fuel lol(individually)
    see if the spark is strong throughout the pack