vtr misfiring over 3000rpm

1. OGSVTR Newbie Joined: Feb 2012 Forfar, Angus Posts: 5 x reg mk2 saxo vtr

   #1 1st March 2012, 21:53

   I know there is loads of post on here about misfiring saxos but was wondering if anyone could narrow it down. The car has had a brand new coil pack and that hasnt solved the problem, i know it could be various things like a sensor or timing off etc but the car runs smooth all the way up too 3000rpm and you can nurse it up too 65mph before it starts too jump. I was going too check crank sensor, map sensor, coolant temperature sensor etc with a multi meter back to the ecu. Before i done that i was just wondering if anyone knew what it could be or where was best to start? cheers.
2. user_36974 Frequent Poster Joined: Aug 2009 Manchester Posts: 570 Mercury Grey VT?

   #2 2nd March 2012, 00:02

   how recent are the plugs ?
3. OGSVTR Newbie Joined: Feb 2012 Forfar, Angus Posts: 5 x reg mk2 saxo vtr

   #3 2nd March 2012, 00:15

   i would assume they were replaced before the coil pack was replaced, i bought it the way it is last night for cheap because the guy couldnt be bothered fixing or finding out what the problem was, so it got put in his garage and left because he had another car. It was put on a diagnostic machine and it said was the coil pack so he put a new one on and it made no difference. I was going to take the plugs out and check them anyway, ive not done any work on it, cause i just got it last night and havent had time was just looking too see what people thought..
4. OGSVTR Newbie Joined: Feb 2012 Forfar, Angus Posts: 5 x reg mk2 saxo vtr

   #4 5th March 2012, 22:30

   anyone got any ideas?
5. adamspencer Infrequent Poster Joined: Feb 2012 Posts: 173 52 Saxo Desire 1.1

   #5 5th March 2012, 22:43

   faulty ecu may cause mis-firing and seeing as it 'selective misfire', as in only over 3K, this may be the culprit. although without replacing it (at very high cost) i wouldnt know how to diagnose
6. user_53433 Infrequent Poster Joined: Jun 2011 Gloucester Posts: 119 1.6 VTS MK1 1997 L3

   #6 5th March 2012, 22:46

   Fuel filter? fuel pressure regulator?
   Try the easy stuff first.
7. Gabbastard Saxperience Post Whore Joined: Dec 2002 United Kingdom Posts: 8390

   #7 5th March 2012, 22:46

   Does it do it at full throttle? If it doesnt, then lambda.
   High gear, low rpm, full throttle? If that causes it,faulty MAP.
   If its just 3krpm regardless of gear/throttle angle, Id put money on crank.
   
   Check theres no moisture in your crank sensor connector; I recently had nearly the same problem. Had moisture in the connector, cleaned it out and greased it... no more problem.
8. OGSVTR Newbie Joined: Feb 2012 Forfar, Angus Posts: 5 x reg mk2 saxo vtr

   #8 5th March 2012, 22:52

   thanks for all your help, yeah its 3krpm full throttle, it doesnt lift higher than 3krpm, thats in neutral seeing as ive never drove the car
9. OGSVTR Newbie Joined: Feb 2012 Forfar, Angus Posts: 5 x reg mk2 saxo vtr

   #9 13th March 2012, 22:41

   turns out it was lambda, changed the crank while i was trying to find the fault aswell