Coked spark plugs

1. Sinque Regular Poster Joined: Nov 2008 Posts: 362 Saxo 1.4 Furio

   #1 23rd March 2012, 15:40

   Hi,
   
   I was experiencing misfires and so checked the plugs which turned out to be as black as night. I wire brushed them down and cleaned them and put them back in. It ran much better.
   
   I took them back out to find they were as black as they were when I first cleaned them. Why are they coking up so fast after a 2 mile trip?
   
   I got some new ones but don't want to put them in if they're just going to end up black after 5 minutes.
   
   Cheers
2. welshpug Saxperience Forum Bum Joined: Jul 2010 South Wales Posts: 3078 ZX 16v, 205 GTI, 309 Goodwood, 405 MI16.

   #2 23rd March 2012, 19:25

   too much fuel going in, ecu temp sensor or lambda usually.
3. tarzan Frequent Poster Joined: Apr 2010 Lurgan Posts: 767 2001 black saxo furio 2001 black saxo vts

   #3 23rd March 2012, 19:27

   try cleaning your TDC sensor they can get clogged with clutch dust. it may even be loose
4. user_16747 Banned Joined: Jul 2007 Posts: 4328

   #4 23rd March 2012, 19:49

   They will clog up if the cars not up to temperature
   
   Take it ons good run, like 40-50 miles including some motorway or dual carriageways
5. Sinque Regular Poster Joined: Nov 2008 Posts: 362 Saxo 1.4 Furio

   #5 23rd March 2012, 20:05

   http://www.saxperience.com/forum/sho...d.php?t=418232
   
   More problems!
6. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #6 23rd March 2012, 20:48

   Also if you go past the service interval with oil changes then you can get a carbon build up.
7. Sinque Regular Poster Joined: Nov 2008 Posts: 362 Saxo 1.4 Furio

   #7 23rd March 2012, 20:51

   The oil got changed about 6 months ago along with the head gasket and then again a few days ago but the problems were occurring before then :/
8. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #8 23rd March 2012, 21:49

   Quote:

   Originally Posted by Sinque The oil got changed about 6 months ago along with the head gasket and then again a few days ago but the problems were occurring before then :/

   In that case try a new lambda sensor.
9. Sinque Regular Poster Joined: Nov 2008 Posts: 362 Saxo 1.4 Furio

   #9 24th March 2012, 13:16

   Brand new plugs ran in the car for a few minutes, a la black!
   
   
   
   Seriously over fuelling to the max. Exhaust fumes visible then disappear for a while like its changing mixtures or something