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?
thanks
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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?
659.
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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:
www.traceyourfamily.co.uk/group001.jpg
Group 004 from enigne cold start:
www.traceyourfamily.co.uk/group004.jpg
Group 13 whilst idling, cyl2 injector was replaced 5k ago, others are original with 100k usage.
www.traceyourfamily.co.uk/group13.jpg
Edited by Richard_Gomm on 29/06/2009 at 12:17
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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....
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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...
659.
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manual gears, it does have the EGR but no cooler as far as I know..
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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...
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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
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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.
659.
Edited by 659FBE on 05/07/2009 at 13:33
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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.
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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.
659.
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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.
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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.
659.
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Richard,
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.
659,
Have you any ideas.
Stuart.
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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.
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Hi have anyboy sorted this problem out? I have a golf
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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.
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