does this camshaft look ok


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does that cam look ok,still not found the problem with the car so wondering if it could be the cams


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cams need to be removed to check


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Car is a 140bhp tdi audi a3 with a BKD engine

The problem is bad smoke on startup (its definatly diesel smoke)
will smoke badly on cold startup and doesnt start very well
the bad smoke on cold startup will stay for a good few minutes if i leave the car on tickover but if i drive the car right away the smoke is gone in a few seconds and it doesnt smoke then unless i turn it off and start it from cold again.
when its warm it starts fine and does not smoke.
when im driving it does feel like i get the odd misfire sometimes

Vagcom says misfire on cylinder 1
I checked my injector readings and i get

cyl1 cyl2 cyl3 cyl4 measured in mg/str when cold
2.99 -3.01 2.79 -2.78

when the car is upto temp it goes to
2.82 -1.6 -0.73 0.45

from what i can gather reading online injector 1 is injecting out of spec and injector 2 is trying to compensate for it same with injector 2 and 3 when cold but when warm injector 2 and 3 are within tollerance but injector 1 and 2 are still struggeling

things iv tried
checked coolant and its not loosing any
fuel pressure is fine
changed glow plugs
changed injector loom
changed injector 1 and when the old one came out had an x on it so from that someone has already swapped them at some point cos iv been told that means they are exchange units
changed tandem pump
changed starter motor
changed the MAF
compression tested cylinders and they were fine
the car has had a full service

Does anyone have any idea what I can try next
i do have a ross tech vag com cable so can check more reading if needed


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Got to be honest, you've done tons of research. The only reason I asked was because my cam in my old PD 150 Golf went down as one of the lobes was worn down. Up until that point there were none of the issues you mentioned. Only way to check the cam is, as mentioned, to remove from the engine.


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There are sealing rings on the injector. There is a repair kit from Audi. Around £18 or so per injector.

We've seen this issue on several 1.9 and 2.0 TDIs.


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well its not cams i can assure you. My guess would be a valve stem oil seal leaking down when its left over night. Poss a dribbling injector ?
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that was my first thought a leaky valve seal or injector but its not an overnight issue,if i start the car leave it running till it clears then turn the car off for 5 mins and start it again it smokes again, but when the car is warm i can leave it for 5 hours and it wont smoke,also its definatly diesel burning theres no oil burning.its a really ****** of a problem to solve,


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My previous 2.0 TDI had a very similar problem......sluggish to start and very smokey. Turns out there was an internal leak across the tandem fuel pump and the oil was getting sucked into the fuel system clogging the injectors and filter. As it was under warranty Audi replaced the pump, filter and injectors. It took them 2 attempts to get a serviceable tandem fuel pump as the 1st one they fitted had the same problem and that was new.


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I'll be very interested to know what the problem is, fair bit changed already.

Curiously, have you had the ecu reflashed by audi, has it had a remap at all?


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iv checked the fuel system for any oil residue and there is none in there.

the car has never been remapped that i know of,on the pistonheads forum a guy on there that seems to know his stuff has recommend i change all injectors and seals,i got a spare engine off ebay the other day with injectors in it so il buy some new seals and fit those in and see if that helps,he also told me to check where the injectors sit in the head as that could have worn giving me issues,im hoping to god that changing all the injectors and seals fixes it as after this im running out of ideas,lol