Engine Idle.

1. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #1 2nd January 2011, 19:26

   Hi all
   
   1st thing in the morning my car starts 1st time after 2mins the cars idle goes between 950-1000rpm & misfires after 5mins it returns to normal & fine for the rest of the day.I am right in thinking its faulty coolant temp sensor?
   
   
   Thanks.
   
   Steve
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 January 2011, 19:27

   Quote:

   Originally Posted by stevo67 I am right in thinking its faulty coolant temp sensor?

   Could be, have you checked that?

   1 user thanked this post: user_20080
3. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #3 2nd January 2011, 19:37

   Thanks for the reply i`ll get a new 1 & swap it over just wondering if anyone else has had the same problem.
   
   Steve.
4. RustySkull Saxperience Post Whore Joined: Oct 2009 Basildon And Corringham, Essex Posts: 5179 MK1 Focus RS, Discovery TD5, Renault Trafic 2.0

   #4 2nd January 2011, 19:41

   Quote:

   Originally Posted by stevo67 Thanks for the reply i`ll get a new 1 & swap it over just wondering if anyone else has had the same problem. Steve.

   I've had similar problems, I've found that little sensor can cause a lot of problems lol.
   
   Why don't you unplug it while your engine is running (Normally) and see if it makes a difference? When mine went if I unplugged it nothing happened, when I put my new one in, and I unplugged it the Engine ran lumpy.
5. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #5 3rd January 2011, 13:02

   On another note can you clean these sensors?
   
   Steve.
6. RustySkull Saxperience Post Whore Joined: Oct 2009 Basildon And Corringham, Essex Posts: 5179 MK1 Focus RS, Discovery TD5, Renault Trafic 2.0

   #6 3rd January 2011, 13:09

   Quote:

   Originally Posted by stevo67 On another note can you clean these sensors? Steve.

   You can give them a clean with a rag and some Carb Cleaner, I don't know if it'll work but it depends how dirty then are when you take them out. If they're corroded, then yeh clean it and see if that works
7. danny-vts Saxperience Post Whore Joined: Dec 2010 Chesterfield/Nottingham Posts: 7147 dead vts. twisted 106 gti. '03' vtrrrr

   #7 3rd January 2011, 15:23

   could be a nooby question plus iv been workin for over 30 hrs so im a little tired lol, where is the coolant temp sensor on a mk1 vts ?
   cheers guys
8. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

   #8 3rd January 2011, 15:27

   If ts as same as my mk1 vtr then on the thermostat housing theres 2 sensors a blue 1 & a green 1 its the green 1 for the coolant temperature the blue 1 is for the temp guage.
   
   Steve.

   1 user thanked this post: danny-vts
9. RustySkull Saxperience Post Whore Joined: Oct 2009 Basildon And Corringham, Essex Posts: 5179 MK1 Focus RS, Discovery TD5, Renault Trafic 2.0

   #9 3rd January 2011, 15:32

   I'm not 100% sure on VTS's
10. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

    #10 8th January 2011, 12:30

    Finally diagnosed my idle problem,driving along today & for a few months theres been a rattle on acceleration well today I get the rattle plus pops & bangs.You`ve gessed it the CAT has completely broken up theres bits of it right through the exhaust system,so its in a garage & needs new cat centre section section & back box.Total cost inc vat £400.00.I`ve been told that what often happens when the cat breaks down you get overfueling low mpg(which i`ve been having) & more importantly where the exhaust gets blockd up you create lots of back pressure which can cause the cambelt to slip a tooth knackering the engine.Luckily i`e caught it i time,phew.
    
    Steve.
11. Railroader Established Member Joined: Dec 2009 Bolton Posts: 1068 Saxo 1.4i sx

    #11 8th January 2011, 13:00

    Stevo, is yours a VTR/S? When the cat goes I am assuming it affects a lambda sensor after the cat in the exhaust pipe, to give you shitty mileage?
    
    In me 1.4 theres only one lambda sensor. My cat just went I repleced with a spare, but Im still getting carp mileage. I took the lambda off and it was black and look like it had been melting as it was leaning. put a spare lambda on today but it still seems to be guzzling, maybe too soon to tell, and Ive got a slight misfire on all 4 at high load
12. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

    #12 8th January 2011, 13:29

    Hi mate
    
    Its a mk1 vtr ,1 lambda sensor on the downpipe the cat is under the car.
    
    Steve.
13. Railroader Established Member Joined: Dec 2009 Bolton Posts: 1068 Saxo 1.4i sx

    #13 8th January 2011, 14:11

    Quote:

    Originally Posted by stevo67 Hi mate Its a mk1 vtr ,1 lambda sensor on the downpipe the cat is under the car. Steve.

    then how can the cat failing cause it to overfuel?
14. user_20080 Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.

    #14 8th January 2011, 16:43

    Just to add to the problem yes the CAT fell to pieces the mechanic also said that when a lambda sensor fails it affects idling on cold start up because it has its own heating element.Once its heated up then the idle is fine he also said maybe a MAP sensor fault & not to get a generic lambda sensor from ebay because they cause probems too.Hope this clears up any confusion lol.
    
    Steve.
15. citroen_saxo_vtr Saxperience Forum Bum Joined: Mar 2006 Norwich Posts: 2823 Vectra sri 2.6 v6

    #15 8th January 2011, 16:59

    My words to that mechanic would be bullshit! the cat is after the lambda so it wouldnt hardly effect the running at all but i do agree if the cat has broken up the engine wont get rid of the gases and will play up. £400?????? a cat is £70-80 new and a center £30 and rear £30 all give or take, your being charged atleast £200 labour and its an hours job max!! I changed all my system in 25 mins.