Misfiring - Changed Spark Plugs and Coilpack - ECU??

1. NICK2506 Saxperience Post Whore Joined: Apr 2008 Surrey Posts: 6424 Black '03 Mk2 VTS

   #1 5th April 2011, 16:45

   Cars been misfiring, was oil in the spark plug hole which when i took it out ran into the cylinder. sprayed Wd-40 in the hole and put the old spark plug back in and ran the engine to clean it out.
   
   Changed the spark plugs,
   
   Changed the coilpack today (£144 )
   
   and its still misfiring! any ideas? 03 plate VTS
2. Bedford126 Saxperience Post Whore Joined: Jul 2010 Morley, Leeds Posts: 8469 Civic ep3 type r powered by TDI NORTH

   #2 5th April 2011, 17:40

   could be a dodgy injector?
3. evans1089 Saxperience Post Whore Joined: Jun 2007 Chesterfield Posts: 8935 Ibiza Cupra 204bhp

   #3 5th April 2011, 17:41

   Look at the stickes. Can be an idle control valve, air mass sensor, or other bits
4. Nick_j_r Regular Poster Joined: Feb 2011 Ruthin North Wales Posts: 308 Saxo VTR, 205 CTI S16

   #4 5th April 2011, 19:09

   Mine did this, check or change the lambda sensor mate
5. NICK2506 Saxperience Post Whore Joined: Apr 2008 Surrey Posts: 6424 Black '03 Mk2 VTS

   #5 5th April 2011, 20:05

   my mate whos a mechanic just checked the continuity in the wires from the ecu to the plug that goes into the coilpack and all fine.
   
   he reckons its the ECU? could this be a possible cause?
6. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #6 5th April 2011, 20:46

   Could be the ECU but the ecu recieves electrical signals from the sensors around the engine then adjusts things.With the engine running try unplugging a sensor(1 at a time)and noting the outcome if the car runs better with that sensor disconnected then that can be the problem(faulty sensor)You can try other things like a compression test as well.
   
   Steve.
7. Bensvts Frequent Poster Joined: Feb 2010 maidenhead Posts: 923 Track Itb'd Mk1 Vts

   #7 5th April 2011, 20:53

   if hes a mechanic get him to do a diagnostic check on it to bring up fault codes etc and point u in a dirrection of where the fault proberly will be, i personal would look at injector if u say u have changed spark plugs and coil pack
8. K17NEY Saxperience Post Whore Joined: Aug 2005 Porthcawl Posts: 5726 FQ Volvo V70R Peugeot Partner

   #8 5th April 2011, 20:56

   There is an adjustment pin on the throttle cable that runs along the top of the injectors, This had worn through the connection to an injector on mine before, This caused a missfire. Check yours.
9. NICK2506 Saxperience Post Whore Joined: Apr 2008 Surrey Posts: 6424 Black '03 Mk2 VTS

   #9 5th April 2011, 21:58

   Quote:

   Originally Posted by stevo67 Could be the ECU but the ecu recieves electrical signals from the sensors around the engine then adjusts things.With the engine running try unplugging a sensor(1 at a time)and noting the outcome if the car runs better with that sensor disconnected then that can be the problem(faulty sensor)You can try other things like a compression test as well. Steve.

   Wicked mate, i'll go round tomorrow and unplug each one, one by one. so if one is faulty then when unplugged the car would run better?
   
   

   Quote:

   Originally Posted by Bensvts if hes a mechanic get him to do a diagnostic check on it to bring up fault codes etc and point u in a dirrection of where the fault proberly will be, i personal would look at injector if u say u have changed spark plugs and coil pack

   he did but it said there were no faults, another reason why he thinks it could be the ecu. will have a look at injectors tomorrow!
   
   

   Quote:

   Originally Posted by kitney There is an adjustment pin on the throttle cable that runs along the top of the injectors, This had worn through the connection to an injector on mine before, This caused a missfire. Check yours.

   Cheers mate, will check that tomorrow and post back! thanks for the help people