Leon cupra slightly rough idle?

mista_khan

Active Member
Jun 16, 2012
82
0
Birmingham
Hi

i dont know if its normal but i have noticed it, after engine has warmed up on my cupra , it idles slightly rough between 780 - 830 revs approx?
like the needle keeps boucning between the above revs, if that makes sense?

is that normal?
 

Mr OCD

Active Member
May 1, 2008
1,974
4
Manchester, UK
Sounds like you have a vac leak ... needle should be steady.

Mind you it could also be the CTS playing around... what temp does gauge show when warmed up - does it move at all?
 
Last edited:

Mr OCD

Active Member
May 1, 2008
1,974
4
Manchester, UK
Im gonna give the throttle body a clean with wynns as well, how much does throttle alignment cost ?

I'm sure someone local to you will do it for free.

DO NOT clean the throttle body until you have someone who can reset it straight after as the car will run like crap without the reset.
 

mista_khan

Active Member
Jun 16, 2012
82
0
Birmingham
I'm sure someone local to you will do it for free.

DO NOT clean the throttle body until you have someone who can reset it straight after as the car will run like crap without the reset.

Oh **** yes i need a vagcom right ? Can i buy one off ebay ? Not sure if i know anyone local
 

Shmoo

Active Member
Feb 8, 2011
224
1
Berwick upon Tweed
it can be done without vagcom. I removed my throttle bodie and left it plugged in. my mate pushed the accelerator so I could access and clean everywhere refitted and works perfect.
 

mista_khan

Active Member
Jun 16, 2012
82
0
Birmingham
it can be done without vagcom. I removed my throttle bodie and left it plugged in. my mate pushed the accelerator so I could access and clean everywhere refitted and works perfect.

i wont be taking it out and yes thats the way i done it on my polo, so can i do it like that on the cupra and not need to reset it?
 

mista_khan

Active Member
Jun 16, 2012
82
0
Birmingham
so lets quickly confirm what im gonna do is the right thing lol,

leave engine on in neutral
take off jubilee clip and remove pipe
make freind rev engine so clip opens and cloese
spray wynns carb cleaner until what comes out isnt black or dirty (without touching butterfly clip)
re join pipe and leave engine on for a few mins

correct?
 

Shmoo

Active Member
Feb 8, 2011
224
1
Berwick upon Tweed
no don't do it with engine running. do everything you have said above but just have the ignition on instead of the engine running and the flap will still open when pedal is depressed.
 

Mannybee

Active Member
Jul 28, 2012
86
0
Norf west
so lets quickly confirm what im gonna do is the right thing lol,

leave engine on in neutral
take off jubilee clip and remove pipe
make freind rev engine so clip opens and cloese
spray wynns carb cleaner until what comes out isnt black or dirty (without touching butterfly clip)
re join pipe and leave engine on for a few mins

correct?

Wrong :lol:

Just ignition on dude:D
 

mista_khan

Active Member
Jun 16, 2012
82
0
Birmingham
Ive cleaned it now, car started up rough but after 2 mins settled. Bad news is needle vibration hasnt stopped ? What would be my next best bet ?
 

mista_khan

Active Member
Jun 16, 2012
82
0
Birmingham
so the revs are still jumping between 790ish and 820, so theres a slight issue somewhere, would anyone else know of this issue on the forum?
 

RDS1972

Active Member
Dec 19, 2011
265
0
Essex
My bet would a small air leak as already mentioned. Not necessarily easy to find unfortunately. How does it run when warm?
 
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