850 t5 black smoke from exhaust on acceleration.

[pamdam]

I was driving today and having some fun with my mate in his bmw behind me, when we stopped he told me whilst I was accelerating hard there was black smokecoming from my exhaust is this normal if not what would cause it?

[volvo]

if you can get your codes read, that would be a good start. My 850 was throwing bad smoke, i changed the temp sender and the lamda and it was cured.

Its better though if you get the codes read so you are not just changing random bits. Do you have any lights up on the dash? Does the car run lumpy when cold?

Cheers

[Nealevo]

mine was the MAF sensor, but get the codes read, it will save you time in the long run!!

[pamdam]

yep I do have the Lambda Light on that came on before christmas when i put on the K&N filter but everyone said its nothing. I've checked the connections on the MAF etc and all seems ok there.
the lambda came on literally first turn of the key after i fitted the filter. Since then it does go off on long drives.

[volvo]

it may just be a coincidence that it came on after the air filter was fitted....Maybe the lamda, maybe MAF hence best get your codes read and go from there

[pamdam]

cheers, i did buy a obd2 reader the other day but then realise i dont have the port in my car. unless im looking in the wrong place ive read that the port should be in front of the gear shifter under a coin holder but i dont have a coin holder.

[volvo]

if its an early one you should have the 2 black boxes under the bonnet, next to the washer bottle on the drivers side

[volvokid]

You sure you ant got a TDi :^) more to the point were you faster than the BM?

[pamdam]

yeah the flashing lights hate reading it that way. I'll do it when i get home tonight.

cheers

[endo-t5]

Black smoke on acceleration is normally fuel ie over fuelling and maybe replace the lambda sensor as I just done mine

[Jamest5r]

Black smoke is defo overfuelling, is your car mapped? changed the injector's? more details you can give mate better chance of sussing it.

[T5frankie]

replace lambda first then maf mate if it doesn't sort it.

[claymore]

Black smoke, phaa, this is black smoke:


http://www.youtube.com/watch?v=GuaPGbS-cPw&feature=plcp&context=C33fed2eUDOEgsToPDskL0xLhNKd1UfmdSfILquck0

[mitchyboy01]

Hi mate, If the car is smoking on WOT then the car is open loop therefore fuelling from MAF calculations so more likely to be that. If it's smoking part throttle (closed loop) then fuelling is calculated via the lambda sensor so more likely to be that.

[mitchyboy01]

Try unplugging the MAF and see if the problem still persists with MAF disconnected. With MAF disconnected your car will use default values with TPS readings so should fuel ok. If problem goes away with maf disconnected I'd say it was that. It will run crap (idle) from cold start though with maf disconnected until the lambda warms up.

or you have put bigger injectors in without a map to suit?

[pamdam]

Right i read the code its code 414 too much pressure on boost. Me and frankie think its mapped but no idea . Only change ive made is filter and mbc but the lambda light was on before mbc was fitted.

[Volvostorm]

Mine put the lambda light on after I changed to a K&N, I took the ECU out for an hour, plugging it back in, it relearned everything, never had a problem after that :)

[pamdam]

You sure you ant got a TDi :^) more to the point were you faster than the BM?


Lol of course it was.

[pamdam]

I tried that before, but now i have read the code the light is out for now.

[T5frankie]

Right i read the code its code 414 too much pressure on boost. Me and frankie think its mapped but no idea . Only change ive made is filter and mbc but the lambda light was on before mbc was fitted.

I said it may have been mapped in the past as ecu strap is gone, but don't know for now it should boost to at least 14 psi he its mapped without the mbc on

[pamdam]

yeah sorry worded that badly I know you didnt say it had been mapped and that it could have been. ive put the standard controller on this morning to test it and it is running around 0.9 bar boost.which i believe is around 12 psi. so it shouldnt be reading as over boost. although after turning the light off it hasnt come back on, even with the mbc on and 1.2 bar boost.
All I need now is someone to follow me and check for smoke.
Thanks everyone for helping I'll post up next weeks problem shortly lol.

[T5frankie]

Standard boost is 10 psi mate

[mitchyboy01]

I think a faulty Inlet air temp sensor or coolant temp sensor can also cause black smoke from the exhaust.