02 1.9TDi white smoke on cold startup. - Richard_Gomm
firstly thanks to everyone whos helped with this problem on the other posts (back in october.) Its still not fixed but I think I'm much closer now. As theres been so many false leads I thought it would be easier to post new (plus didn't want to bump an october 2008 post back up )

The problem is basically white smoke on startup on a passat B5.5, I know its common and I read through the other posts and will try to build the results into this one.

The car is a Passat 1.9 TDI 130bhp AWX Engine 2002 reg.

The white smoke only comes out on a cold start, by that I mean engine left over 8 hours. The outside temperature doesn't seem to make much different (maybe slightly less smoke on a hotter day) Its a dark white, maybe white/blue smoke and smells very sickly and strongly of diesel, the smoke lasts about 10 - 20 seconds, a little gentle reving gets rid of it quickly. The car always fires on the first crank whether engine is hot or cold, however it will run rough for a few minutes before settling out.

Outside temp at this time of the year, ranges from 10 - 20 degree C.

So far the car has had the following work:

glowplugs replaced and wiring checked - all show btwn 11.6V and 12.3V
new wastegate valve
new turbo (old one was on its way out)
one new injector and complete injector harness replaced (due to a missfire)
compression test - good
new MAF
service of all filters & fluids
Coolant sensor replaced and checked to be showing the correct temp.

Inital thoughts from myself and the mechanic is that the smoke smells of unburnt diesel and various ideas were thrown around which resulted in the compression test, which was fine, and then the replacement of the turbo.

Since none of that fixed the problem we started looking at the glowplugs. All were replaced and the wiring checks out. I went out when the engine had been left for 15 hours, outside temp was around 16 C and plugged VAGCOM into the car. I turned the ignition on but didn't crank the enigne. Glowplug light came on and immediately went out (lit for less than a second) VAGCOM showed the glowplug status as 01010000 - which according to the label is Pre Glow not required. I then cranked the engine and watched the smoke come flooding out. THe amount of smoke is enough to see clearly in the rear mirror and be blown across to the fron tof the car before dispersing. Gently reved the car to around 3000 revs and the smoke increased before going after around 20 secs.

The latest test that I ran last night was that I disconnected the Coolant Temp sensor to force the glowplugs on for the 20 seconds. I had to remove the sensor to get to the connect so I lost a lot of Coolant (it was down at Min after) I then left the car overnight.

This morning I've gone out and put the sensor back in the hole but didn't connect the wiring.

Turned the car to ignition and the glow plug came on for a good 20 secs, I then cranked the car and for the first time there was NO smoke!! It still ran rough for a few minutes but no smoke. What I did forget though was to refill the coolant tank before starting the car so the test might be invalid.

Basically my thoughts / questions at the moment:

1. The coolant in the top of the engine was lost when I pulled the sensor out last night. Is it possilbe that the coolant is seaping through somewhere overnight and only getting burnt on the enigne start? The car isn't using any large amount of coolant, I haven't had to top it up for over a year.

2. What sort of temp range does the ECU switch the glowplugs on? I've tried changing it to a longer glow period but it doesn't make any difference. THe light comes on and goes out straight away.

3. Can I know rule out stem valves as it didn't smoke this morning?

4. Would retarded timing be affected by the glowplugs being on longer? Would retarded timing give white wmoke?

I've filled the coolant back up so I'll try again tomorrow, this time starting it will had sat all night with a full coolant tank.

thanks again everyone


{corrected typo in header}

Edited by Dynamic Dave on 29/06/2009 at 10:42

02 1.9 white smoke on enigne cold startup. - jc2
White smoke is definitely unburnt fuel.
02 1.9 white smoke on enigne cold startup. - Richard_Gomm
right, new movement on this -

went out and started the car this morning, again no smoke on startup!! But the place absoutly stinks of diesel, I mean the whole area around the car not just the exhust.....

Whilst under the bonnet I pulled the oil cap off, and for the first time ever I found white/grey smoke coming out in puffs from the oil. There's always been a large amount of pressure and blow out from the oil cap but never smoke before.....

I logged the enitre startup through vagcom and I'll plot it to graphs later so you can all see whats happening with the injected quantity etc.

any thoughts in the meantime?

02 1.9 white smoke on enigne cold startup. - 659FBE
I'll keep quiet until you have a bit more data but from your observations, I would suggest that you may have fitted the wrong type of glowplug. White smoke is partially burnt fuel and may be indicative of a pre-heat problem.

Can you check the part numbers on the invoices and on EKTA before going too far in?

02 1.9 white smoke on enigne cold startup. - Richard_Gomm
Glow plugs were supplied from VW dealer and fitted there, however it was smoking before they were replaced.

graphs from vag com

Group 001 from enigne cold start:


Group 004 from enigne cold start:


Group 13 whilst idling, cyl2 injector was replaced 5k ago, others are original with 100k usage.


Edited by Richard_Gomm on 29/06/2009 at 12:17

02 1.9 white smoke on enigne cold startup. - Richard_Gomm
I've just checked my timing with vagcom and it appears that my car is very retarded which would explain the rough idle and shudder on shut down. It may also add to the smoke problem.

BUT... the diesel smell may masking the real cause for the smoke..

2 days ago when I pulled the coolant sensor out I lost all the coolant in the engine block. I didn't have any extra coolant so I filled up with some water (about 1 - 2 litres) as a stop gap until I could get to VW for some G12.

The car then didn't smoke on startup for the following two days despite the same wheather conditions. Still a strong smell of diesel thou.

Last night I drained the coolant and replaced with the premixed correct VW G12 antifreeze/coolant stuff. next cold start after that (this morning) and the cars smoking like never before, for a good 20 secs then stops.

Is it possible that the coolant is causing the problem?

What part of the coolant makes the smoke? Is it steam from the water side, or is it the antifreeze part? If it is the antifreeze then with me adding that 2 litres of water to the old diluted stuff make it so diluated it wouldn't produce smoke?

I'll disconnect the coolant sensor in the morning (just the wiring this time!!) and see if starts without smoke, at least then we have a definate idea of where the problem is.

If it is the coolant that dripping then were talking small amounts as the level never moves and I can't remember having to add any since I got the car.

Where would the coolant be getting across? theres no mayo around the oil cap, and the oil is a fresh batch put into a few days ago so it still looks quite clean. Any other way to test?

thoughts anyone....
02 1.9 white smoke on enigne cold startup. - 659FBE
Richard, does your vehicle have an auto or a manual gearbox?

The PDs with auto transmissions generally have a water cooled EGR system - which is very prone to leaks. This would give you white "smoke".

Just a thought...

02 1.9 white smoke on enigne cold startup. - Richard_Gomm
manual gears, it does have the EGR but no cooler as far as I know..
02 1.9 white smoke on enigne cold startup. - JohnM{P}
I'm no expert but white smoke that blows around to the front of the engine in this weather and stinks of diesel isn't steam...
You say the timing is retarded - as it's a diesel, it isn't ignition, so is either valve or injection timing. If Vagcom found this, I suspect the latter. If the fuel was being injected too late for complete combustion, then you'd get stinky white smoke. Perhaps one of the regulars here can point you to possible reasons why the timing is retarded, otherwise I suggest you get it to someone who understands these engines...
02 1.9 white smoke on enigne cold startup. - Richard_Gomm
finally had chance to get out under the bonnet. There isn't a EGR cooler as far as I can see.

Disconnected the coolant sensor today and started the car up. Glowplugs were on for a good 20 seconds, and there was still white smoke after crank. It was less than normal but still visible.

I guess we can rule the glowplugs out, I think the extended glowtime obtained by disconnecting the coolant sensor is slightly masking the problem.

So i then made the adjustment to the timing as the other mail shows. As my car was reading 6.6 I decided to take it down to 0 and see what happens. So after a lot of playing I got down to 0.3 and the car was the smoothest I've ever seen at idle, and had no shudder on shutdown. Seemed great. So I went back and tightened the 3 bolts up, and just as my luck would have it I snapped a bolt!!

After all the cursing I then spent a good 20 mins getting the broken thread back out. Eventually got it out only to go and do the same on the second of three bolts :-(

In my defence the bolts looked about 100 years old, I don't think the belt was changed at 80K like I was told, althought he belt does look quite new, either that or they used the old bolts to tighten the unit back up.

Either way got to wait for the shop to open on Monday to go and get two new 13mm bolts. Then I'll be able to see if the timing helps the cold start....

thanks all

02 1.9 white smoke on enigne cold startup. - 659FBE
By coincidence, I've just changed a cambelt on an AWX Passat. The camwheel to hub bolts are M8 with a material specification of 8.8 and a tightening torque of 25 Nm.

Although 8.8 specification bolts are the lowest spec in common use (although perfectly adequate for this job) they are well within their limit when torqued to 25 Nm. If these bolts are breaking, something is very wrong. I reuse these bolts without a thought and there is no reference in the data to suggest renewal.

You should not attempt to "adjust" the timing on a PD engine. The actual timing is determined from the crankshaft position via the speed transducer next to the flywheel. This has 2 sets of "missing" teeth to allow the controller to determine crank position as well as speed. The hall effect transducer and 7 teeth behind the camwheel are to determine which cylinder gets fuel.

It's important on a PD engine to set the mechanical relationship between the crank and cam using the locking tools. Doing this enables the ECU to fire the appropriate injector over the whole range of timing requirements for the engine. If you screw up this relationship, pressurised fuel may not be available from the unit injectors when the ECU demands it.

By "monkeying" with the 3 camwheel bolts, the ECU will attempt to compensate by energising the injectors when dictated by the flywheel sensor. At some operating points, you may not get full fuelling.

Pull the front of the car and use tool T10050 to lock the crank, T20102 (or a 6 mm drill shank) to lock the cam and reset the mechanical timing.

I have thought about the other problems you have and it's getting to the stage where a remote diagnosis is impossible - especially if unscheduled adjustments have been made.

On the balance of the evidence, I think you have fitted the "pre-PD" glowplugs to a PD engine.


Edited by 659FBE on 05/07/2009 at 13:33

02 1.9 white smoke on enigne cold startup. - Richard_Gomm
there's the problem with lots of views... the change in timing was recommend on another forum - no mention you couldn't do it on a pd.

Guess I have some work to do!

As for the plugs there were supplied by allparts, I can't remember the part code - I'll get new ones from dealer.

Don't suppose your garage is based anywhere near hertfordshire? I'm (hopefully) driving the car over and down from hollyhead to london at the end of the month.
02 1.9 white smoke on enigne cold startup. - 659FBE
No garage - just an ex diesel engineer (amongst other automotive jobs) and an interested AWX owner.

There is a possible short cut to pulling the front to restore the camshaft timing. On the Passat, if you look beneath the coolant reservoir there is a hole in the bell housing; the lower edge of this hole has a sharp edge. You can find crankshaft No 1 TDC by looking for a single line stamped on the flywheel edge and aligning it with the sharp edge of the hole as you turn over the engine. (Push the car forwards in top gear - key out).

Obviously there are 2 possible positions only one of which is correct for pegging the engine. To find the pegging position, you want the crank TDC to coincide with the camshaft position where the single position transducer lug (there is only one of these) is at the top. The 6 mm peg then goes in at around 8 O'clock on the camwheel. Alternatively, the cam position is defined by the marking "Z4" (Zund = firing) moulded on the inside back of the cambelt cover, which aligns with the lower of the two camshaft position prongs for cyl 4).

This saves pulling the front to lock the crank with T10050, but you will have to be very careful as you can't peg the crank. In practice, VAG engines are made very accurately and if the marks align, you will not be far out.

Best of luck - these engines are not to be trifled with as they are very sophisticated - more so that they might appear.

02 1.9 white smoke on enigne cold startup. - Hamsafar
Don't worry about the glowplugs. They are not 'required' on these engines for starting or for preventing the problem you have, even in most UK winter weather too. They are mostly there to aid starting in climates colder than ours, and reduce noise and emissions. Also note that the glowplug light is not connected to the glowplugs, it will extinguish when the ECU determines 'ready to start', but the glowplugs will remain on, even during cranking and for up to 3 minutes after the engine has started.
02 1.9 white smoke on enigne cold startup. - 659FBE
Although pre heat is not generally required in a DI diesel at higher ambient temperatures to enable starting, post heat is essential. White smoke is generally partially combusted fuel - the engine makers incorporate post heat in order to minimise this.

02 1.9 white smoke on enigne cold startup. - gromit

Did you ever rectify the problem on your Passat, my 1.9tdi PD 85ps Transporter has the same problem:-

When I start it from cold I get a misfire and some white/bluish smoke for between 5 to 10seconds. It also starts first turn and after the initial 5-10second period runs perfectly.

I have had it in to the VW van main dealer and they checked it out and changed injector number 4 and also fitted a new injector loom and 4 injector seals that cost me £740 + vat!!. I then got it back and it still had exactly the same problem, so they said it might be that the faulty injector over time has gunked up the cylinder and needs a good run with some Forte Diesel treatment to clean it out. I gave it a good run (to the south of France and back!) and the problem is still there. Its going back in tomorrow but they sound a bit a a loss.


Have you any ideas.

02 1.9 white smoke on enigne cold startup. - i love my b5.5 tdi130

I am the same, had vw dub people look at it and loads of other mechanics it starting to become a real problem. please if you or find out what it is please let me know was told needed new exhaust.

02 1.9 white smoke on enigne cold startup. - majeka

Did you get this sorted?

02 1.9 white smoke on enigne cold startup. - newmans
Hi have anyboy sorted this problem out? I have a golf
02 1.9 white smoke on enigne cold startup. - Ballina

I have the same problem with a 99 Passat AHU. Timing was 49, retarded, so I brought it up to 67. Things a bit better but still there. Grey smoke on startup after lying idle overnight and also very smoky on acceleration. I cleaned out the Intake pipes and intercooler, not much oil in there. Two bottles of Forte Injector Cleaner and no improvement.

02 1.9TDi white smoke on cold startup. - rineldi

i've the same problem with my VW golf. please tell me, did you fixed that problem? and how?

thank you

02 1.9TDi white smoke on cold startup. - tw57
Hi I have same prob with 02 passat 1.9TDI 130 AWX has anyone found root cause & if so what was it & what did u do to fix it thanks in advance
02 1.9TDi white smoke on cold startup. - 06-2004sharan1.9tdiPD

Hi, any body found any remedy for this particular problem. I have a 2004 Sharan 1.9 tdi pd 115 and the smoke seems to get more when it is parked for longer. Started it this morning after it had been parked for almost 24 hours and the smoke was everywhere, but subsides after a few seconds.

02 1.9TDi white smoke on cold startup. - audi-pete

Hi, any body found any remedy for this particular problem. I have a 2004 Sharan 1.9 tdi pd 115 and the smoke seems to get more when it is parked for longer. Started it this morning after it had been parked for almost 24 hours and the smoke was everywhere, but subsides after a few seconds.

Hi, any body found any remedy for this particular problem. I have a 2004 Sharan 1.9 tdi pd 115 and the smoke seems to get more when it is parked for longer. Started it this morning after it had been parked for almost 24 hours and the smoke was everywhere, but subsides after a few seconds.

Its a thought, that the white smoke is the result of coolant that has leaked throu the head gasket whilst the engine is not running. when the engine runs the pressure prevents further loss until the engine has again stopped for a while. the coolant loss needs to be little and assume the ammount of coolant mixed with diesel would make it run rougth for a while. so the exhaust gas is a mix of steam and un-burnt fuel til stability returns. seems the head gasket needs replacing, unless I have missed something.

02 1.9TDi white smoke on cold startup. - robini

I am considering buying a Passat with this problem.

I has a newish engine 10K and loads of work has been done to try to rectify the problem. VW have now said it could be the Hydraulic Tappits causing the problem.

It starts fine everytime and once it's warm it's clean.

Until it's warm however if you try to go over around 2000 rpm it blows a lot of smoke, then settles down.

Should I buy this or is it a pup in waiting?

02 1.9TDi white smoke on cold startup. - Kilner

hi i think i have the same problem on my 2.0tdi

take a look at the video and let me kno if its the same


i have no idea what is causing it but it seems to have happend after the vosa injector recall

02 1.9TDi white smoke on cold startup. - BenG

Got a similar issue with my 1.9 PD TDI (ARL engine).

Often (not always) puff out what looks like whitish smoke for a few seconds after a cold start. Could be bluish oil smoke I guess though I can't really tell from the driver's seat. Sometimes runs a bit rough for a second or two, then smooths out and the smoke vanishes.

Has been suggested this could be caused by a leaking injector, allowing some diesel to run into one or more cylinders while the engine is off, which then burns off when the car is started. Would need to remove injectors to test I suppose.

Alternatively, leaking injector oil seals or valve stem seals could be allowing oil into the cylinders. No way of testing this I guess unless seals are replaced.

Or, just dodgy glow plugs and lack of preheat(?). Had a glow plug replaced recently as it triggered a fault code/warning light. The smoking seems more prevalent in colder weather and is not just condensation.

I've not bothered paying for more work to be done as the car only smokes for a couple of seconds and runs perfectly otherwise.

Would be interested if anyone's got a similar issue and solved it!


Value my car