black smoke!

[vw754]

ok,3.8 immissions is no good, its smoking black when reved on idle at high revs,so its failed immisions,what can i do now?

new maf,coolant sensor all filters and still in the tank injector cleaner,especiall recomended for pump deuse engines.

black smoke,cant see any split pipes etc,

 

[inigoj]

If it is not the injector cleaner burning, you have a major leak/pipe off, or boost control problem.

Does the car still run ok? and has it been remapped?

Can you hear the turbo spooling up ok?

 

[vw754]

ive checked everything! car starts first time everytime, drives brilliantly,performs brilliantly...and has plenty of power! cant hear the turbo,but it is working. Not been remapped, i have nothing bad to say about it just black smoke when reved hard at m.o.t test (failed at 3.83)
a bit hevy on diesel,this is obviously why theres more black smoke then neccesary(over fueling,i think...thats what black smoke indicates.)

Its not been re-mapped,but if it did,are these the symptoms you would normaly get with a remap?

 

[inigoj]

Has the car had incorrect oil, or too much oil in it?

If it is driving well but just smokes too much it is unlikely to be a leak etc.

You need to have any fault codes, and the reported/requested fuel/boost values read with vagcom etc.

If your car has a PD engine it is possible that you are burning engine oil that has blown up the boost pipes from the turbo into the inlet manifold.

You may see excessive oil at the EGR valve if this is the case.

Try draining your bottom boost hose, and go for long run to see if it improves.

 

[vw754]

oil does seep out of the small holes on the egr,however after cleaning egr oil is back,i clean it and after 2 weeks its back,i only drive 100 miles in 2 weeks local. car was a bit low on oil and its now topped up,still smokes.

oil is shell helix 5w-30 purchased from audi.
which pipe you on about? thers on going from turbo to airbox,one under that,and one on intercooler.
SMOKE TEST,when accelerating hard,there was black smoke!

TEST NO 1. 2.20
2. 4.31
3. 4.31
4. 3.72
5. 4.54
6. 3.78



AVERAGE READING: 3.83 1/M
ZERO CHECK 0.18 1/M
OIL TEMP 66 c
limit 3.00 1/m

FAIL !!!


These reading have been taken on idle using vag-com.
new to vag-com so took what i could incase you guys spot unusual goings on

(reason is bad mpg,new maf,coolant sensors/filters-no leaks)

fuel temp 64.8 c
intake air temp 25.2

group 013 injectors -0.78, 0.28 ,0.42 0.52

group 004 unit injector valve command: 0.0 ATDC spec inj duration 6.6 CF
syncro angle 0.0 CF

egr 58% (40-75 specified)
maf fluctuating between 230-250 (specified 230-310)

group 005 starting condition start inj quantity 13.2 mg/str

group 009 injected quantity limitation max IQ 21.1 mg/str

group 020 torque 220/240 nm inj quantity in group 020 70.0 mg/str

intake air temp 42.3 c
intake air pressure 994.5
atmos pressure sensor f-96 989.4 mbar
d.cycle map 19.9%

 

[vw754]

This all seem ok....anyone?

 

[Caesium]

If the oil temperature was only at 66 degrees then the garage shouldn't have run the emissions check, the engine was far too cold.
The car needs to be at full operating temperature for a particulate check to be accurate. Give the car a good caning when its hot then run it straight back in for another check without letting it idle for too long.
Even if there are other problems with your car such as a sticky or dribbling injector (causes smoking) the engine should still be hot when tested. Oil should be closer to 130 degrees

 

[nwhiteley]

If the oil temperature was only at 66 degrees then the garage shouldn't have run the emissions check, the engine was far too cold.
The car needs to be at full operating temperature for a particulate check to be accurate. Give the car a good caning when its hot then run it straight back in for another check without letting it idle for too long.
Even if there are other problems with your car such as a sticky or dribbling injector (causes smoking) the engine should still be hot when tested. Oil should be closer to 130 degrees

The initial Diesel test is done at anything above 60 degrees. If this test then fails after 6 attempts, the oil temp will need to be above 80 degrees. If the test is still failed change the oil and replace the diesel filter. This usually works.

By the way, im a MOT tester.

 

[Caesium]

I used to work in an MoT test station, and the krypton particulate machine we had used to fail every car we tried to test so we gave up in the end and checked by eye.

 

[vw754]

thanks for all the info,changed oil and filters (audi parts)
if im driving and i change to 2nd gear and drive steady it throws out a puff of black smoke at around 2,000 revs,ive been told this is quite normal as the turbo kicks in at around 1700-200 rpm,and it will throw a cloud of black then????????????????

 

[inigoj]

By 2000rpm your turbo should have spooled up and be online.

You would expect smoke if you put your foot down at lower rev's, but when you have boost, it should not be that apparent.

Are you sure it has not been remapped?

 

[vw754]

ok,smoke only a little now,been told it may have been the injector cleaner i used. BUT,WHY is it running and driving great with no faults yet returning only this much M.P.G ! when i have been driving locally all week and driving it steady? do they all only do this to the gallon? ive been filling it rite to the filler neck venting it each time until i could not get another drop in! and this is all i keep getting no matter what!!!!!!!!
Air filters still clean after 8,000 miles of use everything else is around 1,000 miles old only. It supposed to be a diesel are all A4 130 TDI'S LIKE THIS? I work it out properly not by what the display says!

OH the only thing ive changed is from 195/65 15 alloys to 235/45/17 alloys slightly bigger tyres but surely cant make a massive m.p.g difference!

my injector reading are 0.78-0.28-0.42-0.52
my friend has the same car but his reading are
0.07-0.09-0.08-0.07 which readings are better? although both are within specified readings mine seem higher,both cars are 130 bhp with similar mileage

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Your Mileage Calculations . . . [/FONT][URL="http://www.mileagecalculator.co.uk/images/empty_fuel.gif"][/URL][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Miles Per Gallon [/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]29.71[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Kilometers Per Litre [/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]10.47[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Litres Per 100 Kilometers [/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]9.55[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Cost Per Mile[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]£0.15[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Cost Per Kilometer[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]£0.09[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Annual Fuel Costs[/FONT][FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]£1305[/FONT]

 

[Macduff]

OH the only thing ive changed is from 195/65 15 alloys to 235/45/17 alloys slightly bigger tyres but surely cant make a massive m.p.g difference!

I noticed in the first post that you said you only drive 100 local miles in 2 weeks. Is that all the driving you do or do you mean that everything else is open road stuff?

I'd say that your MPG is probably OK for local short journeys.

I'd also say that changing the tyres might make a bigger difference than you think. We've got a 130 Sport with that size of tyre and the best I've ever had was about 47.5mpg on a run from Bedford to Aberdeen. We usually fill our tank when it's down below a quarter and don't add any more when the pump clicks off. We typically average high 30s or (if we're lucky) very low 40s.

Don't get hung up about readings. If they're both within specification then they're probably OK.