PDA

View Full Version : Blowback???



Irishpassat
15-06-2006, 12:15 PM
This is my first post and possibly an awkward question. I own a 2005 Passat 130 TDI auto/tip saloon. I recently decided I would change it for the estate version as I need the extra carrying capacity. One potential buyer came to see the car and brought his local mechanic with him. In the course of checking out the car the mechanic turned on the engine and with the bonnet open he proceded to open the oil filler cap and also removed the dip stick. When he did this there was a signifigant amount of smoke coming from both openings. The engine has only 18k on it and was serviced 8 weeks ago! He then said he did not like this and that it wasnt normal. When I asked him why he thought it was so smokey he replied that he wasnt certain but he advised my potential buyer not to buy the car. I have since been told that this smoke or blowback is normal enough and it can be more noticable on some engines than others?? I am not a mechanic so I was wondering if anyone can shed any light on this as not only did it cost me the sale but now I am worried that my engine might not be performing correctly. The car drives very well, my only complaint is that the fuel consumption is poor enough especially on the urban cycle where it is only doing about 30-33mpg...motorway milage is averaging about 40-45mpg...:confused:

glynnd
17-06-2006, 09:02 PM
On the understanding that the car performs fine and does not have an excessive oil consumption issue, then there is nothing suggesting that this is abnormal. If I take the oil cap of my 03 tdi done 100k while its running smoke comes out of it!
Consider this also, gas blow by ultimately starts in the crankcase area. Any blow by gas will exit the rocker cover via the pipe near the front of the vehicle. By removing the oil filler cap and the dipstick the gas will escape easier through these two exits than it will through the breather. Since all engines produce some blow by gases its normal to see this to some degree, and as you have already found some engines allow more gas to blow by the rings than others

glynnd
17-06-2006, 09:04 PM
It may be worth having the pump pressure checked as over fuelling will cause smoking and you should be getting 55 plus on the motorway and around 45 in town

:biglaugh:

Irishpassat
18-06-2006, 11:03 AM
Glynnd,
Thanks for the reassurance, I love the car and it performs exceptionally well, if I cannot find a 130 tip estate I will hold onto my saloon anyway.
I will ge a diesel mechanic to check out the pump pressure to see if it is affecting the economy, I would be very happy to get those figures improved another bit.....:D

apole
26-06-2006, 09:16 PM
Hi,

I have just bought a 2003 passat saloon same as yours. It's done 53k and so far I've averaged the same economy as you are getting. I'm assuming it's down on the manual version slightly due to the automatic.

One thing maybe to watch out for is black smoke on acceleration, these engines do smoke a bit but if it's excessive that can be a sign of overfueling.

Keep us posted as to the outcome!!

Andy