help!!!!!!!!!!!!blue and black smoke

[darbuck]

My 2003 C5 2.0 HDI is billowing out blue and black smoke even after two bottles of fuel cleaner but only at between 1500 and 3000 rpm and more so after idling.i am so sick of this car its always something, I've driven nearly every sort of motor at this stage and nothing has ever given me half this trouble apart from a peugeot em a pattern emerges.

[Stickyfinger]

Black smoke/Diesel = Over-fuel~ check
Blue Smoke/Desiel = Oil or Over-fuel ~ check
White smoke/Desiel=blown Turbo ~ Stop NOW !

(most of the time)

[white exec]

Blue smoke = burning oil.
If blue smoke occurs when accelerating = broken or worn piston rings, or excessive oil getting past the rings
If blue smoke only occurs for a short while after engine is allowed to "over-run" (ie decelerate), then problem is normally worn valve stem seals, allowing oil to be sucked in from the cylinder head/cam/valve area.

Black smoke, yes, excessive or unburnt fuel.
White smoke, produced copiously on acceleration = burning glycol (antifreeze) = head gasket gone.

[darbuck]

Hi sticky and white exec thanks lads Im curious can AFM cause this. She seems to clear after driving really hard but if i let her cool down and or let her idle she blows out constant plumes of smoke until i rally her hard again oh by the way turbo kicks in very late i.e 3000 plus revs

[white exec]

Lack of turbo = lack of air, so probably over-rich fuelling, and unburnt fuel (lack of air = lack of oxygen, so incomplete combustion).

[Stickyfinger]

?? Can that happen on a common rail ?? I really don't know, just wondered if the low Ox reading would lower the fuelling amount ?

[Peter.N.]

Does the engine run unevenly when its smoking?

Peter

[darbuck]

sorry lads internet went down there for a few hours so only getting to reply now. yes it tends to run a bit erratic and feels like it backfires without the bang when revved but idling she purrs and no smoke , its weird because it only started doing this but most surprisingly she has always been gutless regardless of revs but now she seems to have improved poke at high revs and very smokey at low revs. Could this be caused by a faulty sensor or glow plug does it have to be mechanical, all filters are in good nick, no significant increase in oil consumption however fuel economy is now sub 30 MPG which is well under her normal i pulled the maf and the temperature sensor seems corroded where it meets the housing i did change the injector seals recently and yes i did use a cutter very carefully. I'm not a bad grease monkey but this has me stumped and i dont want to keep throwing money at her im going to run lexia on her tomorrow and ill post report hopefully it will shed light i had it on lexia allready but nothing was showing up apart from a brake switch fault in the bsi which i changed to no avail im off to bed and check back in the morning thanks lads.

[Peter.N.]

Its very unusual for these engines to give that sort of problem although not impossible of course. If it smokes and is lumpy at tickover that generally indicates low compression on one or more cylinder or possibly a faulty injector although that is rare.

Try disconnecting the air intake pipe at the manifold then run it and see if it does the same, if it does then the fault is with the engine rather than the ancillary equipment, if it doesn't at least you have narrowed it down to the air induction dept.

Peter

[darbuck]

Hi Peter,she ticks over fine with no smoke but smokes and chugs between 1500 and 3000 rpm and then smooths out again but she will chuck occassionaly over 3000 which i think is a backfire as i say plenty of poke after 3000rpm but struggles to reach 3000 rpm she does smoke post 3000 rpm but not as bad but i presume that this is because of higher temperatures.

[Peter.N.]

That's an odd one. Try disconnecting the air intake pipe from the manifold, that disconnects the turbo, MAF, filter and ducting and see if it makes any difference, that might give some direction.

Peter

[darbuck]

Will do its bucketing rain all day here so have to wait on it to calm down as you say its very odd which is whats concerning me as its not a normal set of symptoms ill try disconnecting and i want to see what lexia throws up after.

[darbuck]

just a point should i disconnect the maf electrically aswell

[Peter.N.]

Just pull the plug out to see if it makes any difference.

Peter

[darbuck]

Hi lads, update tried unplugging maf no difference I did run lexia and there was a load of faults so cleared them and tried actuating turbo via lexia and didn't sound right so checked vacuum pipes again and realised egr and turbo vacs were reversed so swapped over seems to have worked also mpg are climbing so seems to be sorted hopefully could it be that simple. p0110 returned so afm must be kaput again it was a cheapo so will go vdo siemens this time.