Rough running after a trip to the ski resort

Jake_S

Veteran Member
Joined
Aug 14, 2012
Location
Charlotte, NC
TDI
2012 JSW TDI/DSG; 05 Jetta Wagon auto (retired)
My 05 Jetta wagon has started to run rough at idle and under acceleration. There is no noticeable loss of power, but fuel mileage on this tank is less than stellar (470 miles with gauge sitting at 1/4 tank). The rough running started after we went up to a ski resort north of Asheville, NC weekend before last. We were staying at the base of the mountain, so the engine was cold when we started the climb up the mountain. Ambient temp was in the high teens that morning, and the car was up to temp (indicated) once we reached the parking area for the resort.
The car sat in the mid-20 degree weather all day, and sounded rough when started. I let it idle while we loaded the car with out gear and stripped off our outer layers. Since then the car has run rough at start up, though it still starts with a revolution or two of the starter.
I changed the oil when we got home and found oil on the plastic under tray, on the back of the engine, and around the oil feed pipe to the turbo. I checked the oil before we left the mountains and it was about .5qt low. I have checked the oil every morning since and there is no change to the oil level after the oil change.
I suspect I had oil blow by going up the mountain since the engine was cold, and this may have gone through the CCV system. I hope the cam has not decided to round off, since I have zero funds to replace it.

Also, the CEL is not on.

Sorry for the long post, but I wanted to include all the info I could.

Jake
 

Jake_S

Veteran Member
Joined
Aug 14, 2012
Location
Charlotte, NC
TDI
2012 JSW TDI/DSG; 05 Jetta Wagon auto (retired)
That's what I'm thinking as well. I will pull the valve cover tomorrow after work and see what shape it is in.

Jake
 

Jake_S

Veteran Member
Joined
Aug 14, 2012
Location
Charlotte, NC
TDI
2012 JSW TDI/DSG; 05 Jetta Wagon auto (retired)
I just filled up the Jetta today and I calculated a 38.96 mpg return on that tank. This is down from 40.5-41.5mpg but I have been a bit heavy with the throttle too.
Now I wonder if I'm being paranoid ...

Jake
 

TDI-JAY

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Joined
Mar 30, 2010
Location
MIDDLEBORO MA
TDI
2012 Sportwagen 6M
I just filled up the Jetta today and I calculated a 38.96 mpg return on that tank. This is down from 40.5-41.5mpg but I have been a bit heavy with the throttle too.
Now I wonder if I'm being paranoid ...

Jake
That is pretty damn close to your average. My guess is that if you had a bad lobe on a cam & had a weak cylinder the car would suffer more than 1.5 mpg. Run some fuel conditioner, possible the fuel gelled on the mountian? By your info looks like you live in North Carolina, do they treat the fuel for cold weather? Other than that I am no help. Good luck!
 
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LNXGUY

Top Post Dawg
Joined
Jan 10, 2004
Location
Barrie, Ont, Canada
TDI
'05 Jetta TDI Wagon
Your bad mileage is most likely due to the lower temps and longer time for the car to heat up.

I wouldn't lose any sleep over a 1MPG lose for an entire tank.
 

Jake_S

Veteran Member
Joined
Aug 14, 2012
Location
Charlotte, NC
TDI
2012 JSW TDI/DSG; 05 Jetta Wagon auto (retired)
1.9GLSTDI The engine is a BEW backed by the 09A Tiptronic.

LNXGUY The fuel mileage for this tank turned out better than I anticipated. The fuel gauge was at half with only 350 miles on the trip. Normally I am over 400 at indicated half tank. I'm not going to fret over it, but I will inspect the cam this weekend.

TDI-Jay I did not think about the fuel gelling while in the mountains, and I honestly do not know if they treat the fuel during the winter. We filled up before the trip so the car had Piedmont (geographical region) fuel in it and not mountain fuel.

As I said, I may just be paranoid about it.

Jake
 

Jake_S

Veteran Member
Joined
Aug 14, 2012
Location
Charlotte, NC
TDI
2012 JSW TDI/DSG; 05 Jetta Wagon auto (retired)
I checked the cam today and it's fine. No unusual wear and the lifter looked good also. I cleaned the EGR since I had it off, and drained the intercooler also. The engine still feels a little rough to me, but I'm not going to stress over it.

Jake
 

1.9glstdi

Veteran Member
Joined
Jan 13, 2010
Location
J-vill,FL
TDI
2005 passat waggon BHW PD
check your vacuum/tandem pump i had to reseal mine it started leaking oil. and my dar ran real smooth after that it used to have a "rough" kinda spot to it before resealing that pump. Have you checked you alternator pulley?
 

Jake_S

Veteran Member
Joined
Aug 14, 2012
Location
Charlotte, NC
TDI
2012 JSW TDI/DSG; 05 Jetta Wagon auto (retired)
The tandem pump does weep a little. I'll check it when I have a chance. I have not looked at the alternator pulley yet. I did not suspect it since the roughness appears to be from the combustion process.

Jake
 
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