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C20xe black sooty spark plugs any ideas?

Posted: Sat Dec 01, 2012 11:03 pm
by Chally2012
Hi new to the site just wondering if anyone can help I have a cavalier gsi 2000 j reg I have just done a full rebuild new rings big and main bearings new stem seals etc had few teething problems so replaced dizzy hall sensor and coolant temp sensor knock sensor and crank sensor got car running ok sort of but seems to have trouble ticking over when cold but once it's warmed up will tick over but still a bit jumpy so I have taken plugs out to check them and they are black dry and Sutton could his be my problem or is there a problem there due to black sooty plugs any help much appreciated thanks

Re: C20xe black sooty spark plugs any ideas?

Posted: Sun Dec 02, 2012 12:01 am
by planetc
Black sooty plugs suggest it is running rich. Fuel pressure regulator possibly? Does the eml stay off once it is running? Poor belt timing could also make the plugs soot up, as could a blocked exhaust. Do bear in mind though that the plugs will be naturally sooty if we haven't run it for long after starting as it runs quite rich from cold anyway.

Re: C20xe black sooty spark plugs any ideas?

Posted: Sun Dec 02, 2012 12:01 am
by planetc
.... and welcome to the forum!

Re: C20xe black sooty spark plugs any ideas?

Posted: Sun Dec 02, 2012 12:05 am
by planetc
..... and reading through that again I think I would make a fuel pressure check my first priority. If the pressure is too high then it will over fuel badly from cold, but would improve a little as it warms up and the system backs of the duration on the injectors. Oh yes, and check the wires to the cts, they have a habit of breaking inside the plastic sleeve.

Re: C20xe black sooty spark plugs any ideas?

Posted: Sun Dec 02, 2012 11:05 am
by Chally2012
Hi thanks for that will check this today and the eml isn't on now was before when the above mentioned sensors wasn't working right but sorted them but will check what you said cus the car was sitting 4 year while I rebuilt her I am having problems getting the fan kick in when its hot water in expansion tank still cold I have had a new thermostat and new gauge sender unit put on but temp oing up to 100 degrees and no fan kicks in so maybe fan broke what do think thanks

Re: C20xe black sooty spark plugs any ideas?

Posted: Sun Dec 02, 2012 6:28 pm
by planetc
I ran out of breath and passed out, could you put some full stops or commas in so I can try again.