GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV
VW GTI MKVI Forum / VW Golf R Forum / VW Golf MKVI Forum / VW GTI Forum - Golfmk6.com



Go Back   VW GTI MKVI Forum / VW Golf R Forum / VW Golf MKVI Forum / VW GTI Forum - Golfmk6.com > Technical Topics > GTI 2.0T Engine / Drivetrain / Exhaust / Tunes


Reply
 
Thread Tools Search this Thread Display Modes
Old 06-14-2019, 10:00 AM   #1
Buhrady
Passed Driver's Ed
 
Drives: 2013 GTI
Join Date: Sep 2017
Location: Oakville, ON
Posts: 5
Unsolved Issue, Slight Rough Idle - no CEL

After searching dozens of threads I can't seem to find any with the exact symptoms I'm having - looking to the forum for any input.

2013 GTI, 6sp, completely stock drivetrain other than APR stage 1 CAI, APR Catch Can and R8 coils. 85k miles.

I find I have a rough idle 70% of the time at a stop. Not enough to throw a CEL, but enough to be noticeable. slightly rough. This happens when cold, warm, on a short trip, long trips, driving easy, after driving hard, no matter. May be random but I find it is more prevalent on short trips.

Only happens at idle - at speed it's perfect. Pulls fine, no dips in power. Fuel economy good.

Items to note:
R8 coils and plugs at 56k miles
Carbon cleaning (properly, intake off, media blast) at 83k
At the same time, injectors completely rebuilt at 83k
New air filter & OEM fuel filter at 83k.
Always Shell 91 V-Power
Always Motul oil every 5k miles
New-style timing tensioner
Latest rev diverter valve (rev D?) at 83k. Not sure if this would matter here.

I was thinking the above work would fix the problem (and it is better) but still there.

I had the timing checked and I'm still within spec at -2.6
Also scanned the ECU before the above work and it noted random misfires, but again not enough to throw a CEL. Haven't had it scanned after the work.

Maybe intake manifold? Maybe cam position sensor? PCV?
Buhrady is offline   Reply With Quote
Old 06-14-2019, 12:18 PM   #2
torga
FIA World Rally Car Champion
 
torga's Avatar
 
Drives: '11 GTI - 6MT - 2dr
Join Date: Nov 2018
Location: ABQ, NM
Posts: 664
Have you checked your mounts? Engine side, trans side, and dogbone mounts? Any one of these could be your issue, since it sounds like your engine is pretty healthy.
__________________
Build Thread; Slowly But Surely
torga is offline   Reply With Quote
Old 06-14-2019, 12:32 PM   #3
Wascally Wabbit
FIA World Rally Car Champion
 
Drives: Rabbit Diesel/TDI/2.5L
Join Date: Jan 2018
Location: San Clemente, CA
Posts: 655
When you look at the engine is it running rough or just vibrating? A vacuum leak will cause a rough idle. If it's only 70% of the time what is going on the 30% when it is running smooth?
Wascally Wabbit is offline   Reply With Quote
Old 06-14-2019, 01:09 PM   #4
Buhrady
Passed Driver's Ed
 
Drives: 2013 GTI
Join Date: Sep 2017
Location: Oakville, ON
Posts: 5
Quote:
Originally Posted by torga View Post
Have you checked your mounts? Engine side, trans side, and dogbone mounts? Any one of these could be your issue, since it sounds like your engine is pretty healthy.
It's a good thought - I'll take a look. The fact that the ECU had some misfires had me thinking something else, but I'll check and re-scan.
Buhrady is offline   Reply With Quote
Old 06-14-2019, 01:17 PM   #5
torga
FIA World Rally Car Champion
 
torga's Avatar
 
Drives: '11 GTI - 6MT - 2dr
Join Date: Nov 2018
Location: ABQ, NM
Posts: 664
Misfires too, huh? In that case, do you know if your intake manifold is the most recent revision? Have you seen the P2015 code when you've looked?
Sometimes when the old manifold fails, it doesn't hard code a CEL, but you'll see the P2015 code if you scan. Same with a P0300 and a few others corresponding to each cyl that sees a misfire.
__________________
Build Thread; Slowly But Surely
torga is offline   Reply With Quote
Old 06-14-2019, 04:30 PM   #6
Boscogn
FIA GT Champion
 
Boscogn's Avatar
 
Drives: CSG 2013 GTI DSG 4DR
Join Date: Jun 2015
Location: San Luis Obispo, CA
Posts: 1,288
Yeah this is why i preach new intake manifold when u carbon clean literally same labor just pay for parts.

As for mounts I've noticed those are more clunks rather than rough idle but a definite possibility.

I also do plugs every 40k but ur still shy of 10k for that.

Double check for vacuum leaks.

Sent from my SM-G950U using Tapatalk
__________________
Wish List: Golf R InterCooler | 034 Motorsports RSB
NOTE: Please PM me if you are selling anything in my wishlist! Also check out my Build Thread!
Boscogn is offline   Reply With Quote
Old 06-14-2019, 04:32 PM   #7
Boscogn
FIA GT Champion
 
Boscogn's Avatar
 
Drives: CSG 2013 GTI DSG 4DR
Join Date: Jun 2015
Location: San Luis Obispo, CA
Posts: 1,288
I had this same problem i waited till i got a cel which was p2015 intake manifold unfortunately my vin wasn't covered under extended service campaign. So i paid oit of pocket anyway got carbon cleaning while they were in there and it went away.

Sent from my SM-G950U using Tapatalk
__________________
Wish List: Golf R InterCooler | 034 Motorsports RSB
NOTE: Please PM me if you are selling anything in my wishlist! Also check out my Build Thread!
Boscogn is offline   Reply With Quote
Old 06-14-2019, 04:44 PM   #8
Buhrady
Passed Driver's Ed
 
Drives: 2013 GTI
Join Date: Sep 2017
Location: Oakville, ON
Posts: 5
Quote:
Originally Posted by torga View Post
Misfires too, huh? In that case, do you know if your intake manifold is the most recent revision? Have you seen the P2015 code when you've looked?
Sometimes when the old manifold fails, it doesn't hard code a CEL, but you'll see the P2015 code if you scan. Same with a P0300 and a few others corresponding to each cyl that sees a misfire.
Appreciate the input - I'll check the codes again and see.
Buhrady is offline   Reply With Quote
Old 06-14-2019, 04:45 PM   #9
Buhrady
Passed Driver's Ed
 
Drives: 2013 GTI
Join Date: Sep 2017
Location: Oakville, ON
Posts: 5
Quote:
Originally Posted by Boscogn View Post
Yeah this is why i preach new intake manifold when u carbon clean literally same labor just pay for parts.

As for mounts I've noticed those are more clunks rather than rough idle but a definite possibility.

I also do plugs every 40k but ur still shy of 10k for that.

Double check for vacuum leaks.

Sent from my SM-G950U using Tapatalk
The classic VW "well while you're in there, might as well replace..."
I think you're on the right track though. I'll check both.
Buhrady is offline   Reply With Quote
 
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 07:07 AM.


Powered by vBulletin® Version 3.7.2
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.