black smoke

[monkey hanger]

although running fine my surf has started to kick out VERY black smoke (heavily) when accelerating(dont matter how light or heavy your foot is!) and also I think when I shut down the throttle ie slowing at a junction etc?
this amount of smoke is excessive and not what I would consider "normal diesel" smoke, injectors have been checked fuel pump turned down slightly,
air filter checked, and of course the usual fuel additives (red ex etc) tried!
I am of the mind that the ecu is asking for to much fuel to be delivered to the engine, and am thinking perhaps a temp sensor is not functioning? and thinks the engine / air is cold? reason for this thought is if I really screw the thing for a few miles (at least 30mins) the smoking stops and it is as clear as a bell until its cooled down again? at which it does its destroyer laying a screen trick again? anyone help? Im after a new series 3, 3 ltr and want this sorted before I sell it on?
cheers Keith

[Smurf]

Hi
If it is chucking out black smoke on over-run the normal cause would be worn valve guides or perished valve guide seals, if it is the seals it is a fairly easy fix and can be done in situ.
Does it burn any oil?????
If it's not using much oil then it is probably over fuelling as you suspect but i dont know one end of a diesel pump from the other so cant help there!! sorry

[mart 870]

wouldnt the worn valve guides put out blue smoke like a two stroke and not black smoke? The bottom end of the stock car is well past its sell by date and at the end of the straights you can clearly see blue smoke from the exhaust - in this case its worn bores/rings letting oil past but you get that little extra power with a nice loose engine lol

[monkey hanger]

no its not burning oil its definately fuel supply? trouble is I am only guessing at the signals the ecu gets? anyone know exactly how the fuel demand for any given condition is met?
cheers Keith

[Smurf]

Sorry, as i said, diesel pumps are not my strong point and neither are ecu's!!
Mart..... yes, it would be blue smoke, wrote the post then thought DOH!!!!!!!
What sort of stock car racing do you do????? oval circuits???? i used to crew for a guy on the oval tracks who ran National Hot Rod.

[mart 870]

Hiya Smurf,

I race Brisca F2 stock cars, mainly in the midlands on tarmac tracks such as Northampton and Buxton, how long ago did you spanner for the Hot Rod?

[kevb]

sounds like too much diesel.you said you got the pump turned down,did that help?maybe check if egr valve is working properly if it has one.i dont know what engine you have.thats all i can think of at moment

[Smurf]

Mart
I remember them!!!! The last time i went racing would be about 5 years ago now, used to spanner for "smiffy" 491, i must get around to going to a few meetings soon!!

[monkey hanger]

well I am not so worried now? took it for an M.O.T flew through no probs whatsoever went to 2.6 initial rev then straight back to 00.08 avg so cant be bad?
cheers Keith