Misfire on cold startup-unless i put my foot on the accelerator

1. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

   #1 3rd May 2011, 20:42

   Ok ive been here a before and got a few suggestions and its never realy got anywhere. So here goes again :
   MK 2 Third phase engine. VTR (silver if that helps )
   
   As the title suggests I have a misfire problem, it doesnt seem to just do it randomly however has done about a year ago, so il ignore that. The misfire occurs approx 2-4 seconds after i start up from cold (IE engine hasnt run in a fair few hours), It judders and no power etc until i turn it off and on again whereby it will be fine just with engine management light still on. Had it read and the faults were random multiple misfires on cylinders 1 2 and 3.
   
   If i start it and imediatly put my foot onto the accelerator, keeping the revs just above 1k (Off idle basicaly) then it will not misfire! I thought perhaps icv which i took off and cleaned, however if it was icv my revs would be all over the place (although they are a little slow to come down). I did origionaly try new coil pack, spark plugs, fuel filter and ive had the inlet manifold off and the injectors out to see if theres anything obvious.
   
   Anything you can suggest? Would be mint as i cant be bothered with buying a new cat for the next mot (Misfiring burnt out my old one)
2. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #2 3rd May 2011, 22:30

   I`ll be interested to see the outcome on this mine has started doing this, this morning & i`ve changed the same parts as you have too.
   
   Steve.
3. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

   #3 3rd May 2011, 23:24

   Yeh ive talked to 3-4 members in the past who have had the same problem and not found a cure. Also seen and made a few threads about it but they lead to nothing or the usual coil pack etc.
4. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

   #4 3rd May 2011, 23:25

   It was suggested that Injection Relay under the ECU might sort it. but i havent been able to source one or any explainations etc, you tried that?
5. user_12308 Saxperience Forum Bum Joined: Nov 2006 The Lang Toun Posts: 4133 Mk2 Clio V6 #007 of 354

   #5 4th May 2011, 03:44

   Do the revs drop away then pick up again? Constantly go from 1000-750 revs at idle?
   
   I had this problem and changed nearly every sensor that the ecu needs a reading from to run the engine. Turned out it was the engine temperature sensor.
6. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #6 4th May 2011, 07:37

   Quote:

   Originally Posted by mtpagey Do the revs drop away then pick up again? Constantly go from 1000-750 revs at idle? I had this problem and changed nearly every sensor that the ecu needs a reading from to run the engine. Turned out it was the engine temperature sensor.

   I`ve changed that 1 as well its fine later on in the day just cold starting is a problem.
   
   
   Steve.
7. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

   #7 4th May 2011, 18:49

   I wreckon my temp sensor could also be faulty. but only very slightly as revs go from 700-870 constantly acording to the plug in elm diagnostic jobby. i can also make it go from 5/600-1100 if i tap the throttle randomly (only somtimes)
   
   But as stevo said, its the cold starts that are the problem!
   
   I may have found a donor MK1 VTS (Full car with knackered shell)...not sure if it would fit the car, posted a thread asking! Ive enquired about the car anyway
8. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

   #8 6th May 2011, 17:56

   I think this thread is going downhil like the rest.....
9. Mysticp Scotland Joined: Jul 2005 Edinburgh Posts: 9556 Saxo 1.6i 16v VTS, 2 Classic Minis

   #9 6th May 2011, 18:16

   Gremlins like this are the worst kind mate, so many possibilities, just keep going replacing things logically, if you have a doner loom you can borrow with sensors thats ideal too!
10. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

    #10 6th May 2011, 19:54

    The donor doesnt seem to be coming through for me. and that was only so i could swap the engine. I wouldnt be finding the route of the problem ha
11. chinkostu Saxperience Post Whore Joined: Aug 2008 The wrong carpark Posts: 5152 Xantia 1.9TD

    #11 7th May 2011, 11:30

    Mine does exactly the same. Had every sensor off and cleaned and nothing!!
12. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

    #12 7th May 2011, 15:18

    Cleaning probably wont do much to be fair. Worst thing is i cant even take them off to see if it makes a difference to while running,as once its up and running the problem goes away.
13. SidnySaxo Regular Poster Joined: Dec 2010 Posts: 369 00 VTR Saxo

    #13 7th May 2011, 15:23

    Had dis problem awhile ago and it was a bottle ov injecter cleaner and a good service got rid ov it
14. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

    #14 7th May 2011, 15:35

    Used injector cleaner. Define good service? ive swapped oil, oil filter, fuel filter.
    
    Was it this exact problem you had or just a misfire?
15. SidnySaxo Regular Poster Joined: Dec 2010 Posts: 369 00 VTR Saxo

    #15 7th May 2011, 15:40

    Why do people only change oil,oil filter and fuel filter.. What about probly the four most important things in the car... The spark plugs!! U gave ur car a 50/50 service man.. Plugs are menta be changed every 8000miles for good performance out ov the car.. Get urself a set ov plugs and get them into ur car and ul see the diffrence!!...
16. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

    #16 7th May 2011, 15:58

    Care to read the thread? Done that
17. chinkostu Saxperience Post Whore Joined: Aug 2008 The wrong carpark Posts: 5152 Xantia 1.9TD

    #17 7th May 2011, 19:33

    Quote:

    Originally Posted by SidnySaxo Why do people only change oil,oil filter and fuel filter.. What about probly the four most important things in the car... The spark plugs!! U gave ur car a 50/50 service man.. Plugs are menta be changed every 8000miles for good performance out ov the car.. Get urself a set ov plugs and get them into ur car and ul see the diffrence!!...

    changed spark plugs and coil pack and mine remains
18. cam123 Newbie Joined: Apr 2011 birmingham Posts: 13 black vtr mk2

    #18 7th May 2011, 20:10

    crack shaft sensor
19. stured Infrequent Poster Joined: May 2009 York-Hull Posts: 222 Saxo VTR MK2

    #19 12th May 2011, 21:16

    Quote:

    Originally Posted by cam123 crack shaft sensor

    Wouldnt that produce the fault at all times? Instead of only at start up?
    
    Also, somones had a similar fault (Its real hard to get info out of him) and they had a garage replace the full exhaust system, and so far its fixed. I wouldnt have thought exhaust would cause a misfire problem....what with aftermarket exhausts/straighthrough pipes being fine
20. rob14f Newbie Joined: Sep 2012 prestatyn Posts: 1 saxo 1.4 furio

    #20 30th December 2012, 00:27

    i thought i would bring the thread back alive as ive got the same problem with mine , had new timing belt and head gasket 6 months ago, and a full service including plugs and valve clearances any ideas guy before i get the hammer to it