rough idle, 5-spd

airwolf

Veteran Member
Joined
Jul 25, 2006
Location
Cassopolis, MI
TDI
None
bergy said:
My dealer told me about some possible issues with bad injectors allowing backflow of the exhaust soot through the injector and contaminating the fuel, but never a burnt o-ring. Just sounds like soot on the o-ring.
If your injectors were leaking that bad to allow exhaust to flow back up into them, I would also think they would allow way to much diesel in, or hydro lock the engine.
 

bergy

Member
Joined
Mar 19, 2000
Location
SLC,UT,USA
TDI
2006 Jetta TDI
I never know what to believe when the dealer tells me something. I find there is little expertise when it comes to diesel mechanics at the dealer. I guess they have not had enough time over the last 10 years to figure out how this type of engine works. :mad: I must admit I have rarely been overwhelmed by any mechanics knowledge of engine repair.
 

10-cc

Well-known member
Joined
May 22, 2002
Location
Montreal Canada
TDI
Jetta TDI 2006 Platinum Gray
Just wanted to share this with you:

The Dealer finally changed all injectors and the rough idle is gone! Apparently the O-rings on the injectors were leaking (oil got into the the return fuel to the fuel tank and contaminate fuel filter injectors etc. So they changed all injectors changed fuel filter and clean fuel tank.

PS: the first thing they did is advanced the timing to 0 from -2 and it did not help.

Bye.
 

Mach1

Vendor , w/Business number
Joined
Sep 27, 2005
Location
Spicewood, Tx.
TDI
05.5 Jetta 5 spd, 06 Jetta DE DSG, 04 F250 6L, 2000 F250 7.3L
Do you burn any BIO???

You had a weak/bad injector..
 

Mach1

Vendor , w/Business number
Joined
Sep 27, 2005
Location
Spicewood, Tx.
TDI
05.5 Jetta 5 spd, 06 Jetta DE DSG, 04 F250 6L, 2000 F250 7.3L
Yes, if a person knows how to use the Vag-com to the fullest extent..There are all kinds of measuring blocks in the software, I have seen cylinder contributing screens in the software, I need more time to familurize myself with what I am looking at..
 

dschein

Veteran Member
Joined
Jul 21, 2006
Location
Reading, Pennsylvania
TDI
None
Mach1 said:
Yes, if a person knows how to use the Vag-com to the fullest extent..There are all kinds of measuring blocks in the software, I have seen cylinder contributing screens in the software, I need more time to familurize myself with what I am looking at..
I've used them for gas engines and (like you) need to look at the ones for our engine.
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
I don't interpret his post as driving the car hard, just exercising the systems and keeping boost up. This can be done without punishing the car. While driving it like you stole it may be fun, it isn't really the best thing for the car. YMMV
 

crisi13

Member
Joined
Aug 5, 2008
Location
Hampton Roads, VA
TDI
06 Jetta 5spd
So I took my car to the dealer yesterday to have the fix for this done. I used the dealer since they are actually listed on here in the TDI mechanics by state thread and I still had a little bit left before the factory warranty ran out. I'm also a little scared to do this by myself and I don't have a vag-com yet. To be safe, I printed out the step by step instructions in this thread on how to fix the problem.

The tech himself gave me a call and thanked me for the instructions and then told me although they would more than likely work, there was technically nothing wrong with the vehicle and that since is what still set to factory specs he could not do this due to liabilty issues. He said that there was a possiblility that it would affect the upper power band. So...back to square one!

Does anyone have pictures of this fix? I know the instructions said that it was so simple that pics weren't needed...but I'm a little apprehensive. Thanks!
 

hid3

Banned
Joined
Apr 28, 2007
Location
Lithuania, Vilnius
TDI
Golf V 1.9 TDI-PD 105 HP
After I had my Timing Belt changed by a local shop I noticed that sometimes I have "rough idle". When the TB was changed, nothing in electronics was ajusted.

I DO HAVE a Vag-com. Could anyone please tell where/which Vag-com settings/measuring should I check? Or what adjustments I might want to try?

Thanks in advance.
 
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dschein

Veteran Member
Joined
Jul 21, 2006
Location
Reading, Pennsylvania
TDI
None
hid3 said:
After I had my Timing Belt changed by a local shop I noticed that sometimes I have "rough idle". When the TB was changed, nothing in electronics was ajusted.

I DO HAVE a Vag-com. Could anyone please tell where/which Vag-com settings/measuring should I check? Or what adjustments I might want to try?

Thanks in advance.
Look here :D
 

hid3

Banned
Joined
Apr 28, 2007
Location
Lithuania, Vilnius
TDI
Golf V 1.9 TDI-PD 105 HP
Not sure if I need to do that. Mine rough idle is very rare and it's difficult to reproduce, besides is happens on cold engine (coolant below 90 C) so don't wanna screw things up (yet). Would like to check with Vag-com if I have something wrong/out of range...
 

dschein

Veteran Member
Joined
Jul 21, 2006
Location
Reading, Pennsylvania
TDI
None
hid3 said:
Not sure if I need to do that. Mine rough idle is very rare and it's difficult to reproduce, besides is happens on cold engine (coolant below 90 C) so don't wanna screw things up (yet). Would like to check with Vag-com if I have something wrong/out of range...
:confused:

Have you read the thread? It tell's you what block and field to use in VCDS to check your timing.
 

SwimmerDave

Veteran Member
Joined
Sep 1, 2002
Location
Decatur, GA
TDI
2014 JSW 6MT
My 2006 A5 seems to have the same "lumpy idle"

My 2006 Jetta manual with 52,000 miles on it drives and mostly idles fine. The exception is when coming to a stop after a highway run of about 5 miles or more. It has a "lumpy" idle almost like 1 cylinder is mis-firing - very rough and annoying. It doesn't seem to matter whether or not I have my foot on the clutch or idle in neutral. The only thing that seems to "help" the lumpy idle is if I blip the throttle just a tad or otherwise turn on the A/C to put a load on the engine.

I've also noticed it's a bit more difficult to start out in 1st gear versus my 2002 A4 manual. My 2009 DSG runs and idles beautifully - smoothest diesel I've ever owned, though I'm holding my breath on the DMF.

I bought the 2006 last week from CarMax and didnt' notice any problems during the test-drive, but we also didn't do a long highway run. Though I'm still on whatever fuel they filled it up with and haven't done any other maintenance other than put new tires on it, I'm pretty sure the problem - after reading this thread - is retard timing.

The car is in warranty - still under 60,000 miltes - so I could reasonably argue that ( (educated guess) retarded timing is out of spec, so they should tune it to spec.. I'll also show this thread to the service tech. and ask him/her to adjust it +2.

I've scheduled an appointment with a local dealer for 2009-05-21 (05/21/09 on this side of the big ponds), so I'll keep you posted on how it goes - or doesn't go.

Cheers,
David
 

TornadoRed

Top Post Dawg
Joined
Aug 3, 2003
Location
Saint Paul (ex-San Diego)
TDI
2003 Golf GL 5-spd, red; 2003 Golf GLS 5-spd, indigo blue; 2003 Jetta TDI wagon, Candy White; 2003 Jetta TDI wagon, silver
SwimmerDave said:
My 2006 Jetta manual with 52,000 miles on it drives and mostly idles fine. The exception is...
While it is still under warranty, have one of the gurus remove the valve cover and have a look at the cam lobes.
 

SwimmerDave

Veteran Member
Joined
Sep 1, 2002
Location
Decatur, GA
TDI
2014 JSW 6MT
TornadoRed,

Good point and thanks for mentioning that !

I just started catching with the reading on the 2005/2006 PD 100's and ran across the excessive CAM wear thread. With 52,000 miles on my '06, there's a good chance for premature CAM wear :-(
 

SwimmerDave

Veteran Member
Joined
Sep 1, 2002
Location
Decatur, GA
TDI
2014 JSW 6MT
Unfortunately, the service department at the local VW dealership I went to was as cooperative as can expected - some, but not very. While they trusted what I said about the symptoms - lumpy idle but otherwise fine - they did not get very far into the investigation beyond reading the computer.

No codes were set and they simply said to try changing the fuel filter. The technician didn't believe timing would fix/affect the issue, but I get the impression he also doesn't fully understand the issue. He seemed very reluctant to adjust the timing just on my say-so. He did admit, however, that he could not measure the timing from the computer...which is a bit strange. Either I didn't communicate effectively, I don't understand what I think I understand, or their computer has less capability than VAG-COM.

I'll change the fuel filter per their recommendation, even though I don't believe it will fix the problem. Fuel filters for PDs are relatively inexpensive - just a filter now instead of the whole housing like in my '02 ALH.

Fortunately, they didn't charge me for their time to try and diagnose the problem. So, the only thing "wasted" was my time.

I was running late for work and didn't ask them to check the CAM lobes for wear, but will do that when I replace the fuel filter and take it back to get them to look at it again. If they're willing to diagnose for free just at the cost of my time and are nice about it (so far they have been), I'll probably take advantage of their time as long as they're willing to offer it and my car is in warranty - 8k left to go !
 
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TornadoRed

Top Post Dawg
Joined
Aug 3, 2003
Location
Saint Paul (ex-San Diego)
TDI
2003 Golf GL 5-spd, red; 2003 Golf GLS 5-spd, indigo blue; 2003 Jetta TDI wagon, Candy White; 2003 Jetta TDI wagon, silver
Dave, you have two TDI experts in the Atlanta area. Ask one of them to help with the diagnosis.

The VW dealership has no motivation to find a solution to your complaint. They do not want to diagnose a problem during the warranty period... they would prefer to wait for something to fail afterward.

We search out and publicize the TDI gurus, TDI experts, TDI pros for a reason -- because we typically do not find their level of skill and competence at VW dealerships.

Just because warranty service is free and independent mechanics must be paid, is no reason to stay away from the independents until after the warrant has expired.
 

Airplane MD

Veteran Member
Joined
Aug 28, 2001
Location
Birdsboro, PA
TDI
'06 Jetta pkg 1
Last post to this thread was just after the dealer (Vision, Reading PA) had replaced the flywheel in the spring of '08. Had myself pretty convinced that this was the problem as it felt fine for 6 or 8 weeks. I got a chance to examine the flywheel and I have to admit, there was nothing obvious wrong with it. Then I started to notice it again. Continued on till this spring when I figured I needed a solution before the Warranty expires in November.

Took it in a couple of weeks ago but of course the test ride showed nothing. The dealer, to their credit asked to have the car for a few days to drive it around. They gave me a 2.0T Passat gasser for a courtesy car for a week while they decided to install another flywheel and this time a clutch. Didn't care much, as the Passat was pretty fun to drive although 25 MPG on premium ($3.09) was an eye opener.

Got a call Monday that they would drop off my car at work and to give it a try to see what I thought. Didn't even make it home before I got the symptom. Lumpy idle coming off an 8 mile run on the freeway. Drove it one more day just to be sure before I called Vision. Without hesitation they exchanged it, this time with a Tiquan (sp?). Side Bar: What is the purpose of this car? Drove nice and straight though.

Two days later, yesterday, they brought it back to me at work after setting the timing to +2. I'm pretty sure I had discussed this with them in the past but apparently VW tech support suggested this to them. Well, first I was concerned there would be a performance hit but all seems well. Actually overall it seems even smoother with no hint yet of lumpy idle syndrome. Also I topped the tank so I can see what happens, if anything, with MPG.

Gotta say, the Vision Dealership has done all that I would ever expect. Too bad they had to go through all this trouble if it was only a matter of a timing change, but as they say, they were only following orders. I assume they'll get paid. Plus they told me I have the latest revision of the flywheel, whatever that is.

BTW: Swimmer, I would check that warranty period. Both my '06s are only 48 months or 48,000. I don't believe there is an extended drive train on this one but correct me if I'm wrong.

So here's a qualified shout out to Sal at Vision. Thanks for your help and keeping this work order open until I tell you it's OK to close. Next time, maybe you could drop off a Phaeton.
 

Airplane MD

Veteran Member
Joined
Aug 28, 2001
Location
Birdsboro, PA
TDI
'06 Jetta pkg 1
Yeah well Jerry, why don't you send me one of those Passat Diesels from the Continent. That's what I really want! Unavailable in the States.
 

hid3

Banned
Joined
Apr 28, 2007
Location
Lithuania, Vilnius
TDI
Golf V 1.9 TDI-PD 105 HP
Heh :D It's popular in Europe (not UK of course) to import cars from US since it's cheaper than buying it here. I think it's time for US people to start shipping cars from EU to US :) Really we have a wide choice of engines here... Wanna Passat? CC or just B6? Wanna diesel, yeah? With DPF or without it? Want 105 HP, 130 HP or 150 HP?! Yeah, that's true! :D
 

FXDL

Veteran Member
Joined
Oct 27, 2009
Location
Barrie Ontario Canada
TDI
2015 Jetta TDI with DSG
My did the same at idle but with the AC on smoothed out .Would also miss when driving some times, acted like the engine shut down for a second and then normal again. In the end it was the cam on it's way out and now is getting a new cam and lifters.The cam lobes on mine where starting to peel I believe. Have the cam lobes checked by someone who knows what they are looking for.
 
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eli

Veteran Member
Joined
Oct 22, 2002
Location
I-95
TDI
2017 Cruze stickshift 2019 Terrain
Ouch. TFS, but thanks for letting us know. can lobes be checked with less labor hours than swapping the cam?

how much is/should-be the lifters+cam job?

Mine missed bizarrely yesterday a few times in a second on the highway, as if i was hitting the rev limiter :|

I'll guess i'll be revving the pontiac V8 while I evaluate/park TDI for trade/repair options, most likely seems to be a chevy cruze 1.8 stickshift or "eco".
 
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FXDL

Veteran Member
Joined
Oct 27, 2009
Location
Barrie Ontario Canada
TDI
2015 Jetta TDI with DSG
Was at the shop talking with my mech., and he showed me a cam out of another BRM and the cam lobe had worn flat at smallest curve of it, which would be the opening part and it was worn to the point it was flat and no longer round . It was flat to the point of some what squared off rather then round as it should be so there fore was inproper lift and chewed up the lifter too. All the lifters were starting to wear in the center and down the road would have worn wright through like number 3 had. The cams ram too too fast so it looks that to some point that there is so much pressure at the high point of the cam and lifters you get the wear and or peeling of the cam surface and then the wear happens real fast then
 

R-Sixxer

Veteran Member
Joined
Feb 22, 2006
Location
Edm. AB
TDI
06 1.9L
Been a while since I'd been around here but I was able to locate the lumpy idle I was having. I hooked up the VAG-COM and noticed a fuel temperature sender was bouncing from zero to max, which aligned with the sound of the lumping. Unplugged it and the problem went away. I eventually replaced it and have not had the issue come back. It's located on the front, driver side of the engine.

http://www.idparts.com/fuel-temperature-sensor-g81-a4-bewa5-brmb55-bhw-p-1758.html
 
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