Hunting idle, anoying problem !!

[bree9482]

Hi guys,

have had some assiatance regarding this issue from a few members now, and l must say the help is awesome(tuffty,prawn,klappe)

So it all started when l first bought the car, which is a 2002 1.8T, AUM A3.

I had this erratic idle. I have so far done the MAF, Cleaned the Throttle Body, injector Cleaner x2, 1 coil pack, replaced a burst breather hose. The MPG has increased thanks to the new bosch MAF, the car feels quicker thanks to the replaced hose, but i still have this idle problem.

I have been advised to d a throttle body adaptation, ill get to that later. Also it has been suggested l have a problem with an o2 sensor as a fault code that had been prev read by a garage said: bank 1 sensor fault, system too lean. This was cleared when the new MAF was fitted.

here is a vid of what im talking about:

https://www.youtube.com/watch?v=T3VCbVf4jgc



So again from a members guidance l bought a ebay cable and downloaded VCDS lite. The cable arrived today

I have hooked it up and all is well, its comunicating with the car. I have done a scan for fault codes and here is what it displayed:


VCDS-Lite Version: Release 1.2
Wednesday, 31 July 2013, 17:45:32.




Chassis Type: 8L - Audi A3/S3
Scan: 01,02,03,08,15,16,17,22,35,37,45,55,56,57,75,76

-------------------------------------------------------------------------------
Address 35: Centr. Locks Labels: 8D0-862-257.LBL
Controller: 8D0 862 257 E
Component: CV-Pump, Alarm, RC D17
Coding: 15178
Shop #: WSC 01236
VCID: 2F1190BFFE05
11 Faults Found:
01367 - Central Locking Pump Run Time Exceeded (Likely Leak)
35-00 - -
01371 - Shareware Version. To Decode all DTCs
35-00 - Please Register/Activate
01372 - Shareware Version. To Decode all DTCs
35-00 - Please Register/Activate
01374 - Alarm triggered by Terminal 15
35-00 - -
01370 - Shareware Version. To Decode all DTCs
35-00 - Please Register/Activate
01369 - Shareware Version. To Decode all DTCs
35-00 - Please Register/Activate
01368 - Alarm triggered by Luggage Compartment Switch
35-00 - -
01366 - Shareware Version. To Decode all DTCs
35-00 - Please Register/Activate
00991 - Shareware Version. To Decode all DTCs
28-00 - Please Register/Activate
00956 - Key 2
09-00 - Adaptation Limit Surpassed
01134 - Shareware Version. To Decode all DTCs
49-10 - Please Register/Activate - Intermittent


So i have read threads about doing the throttle body adpt, l watched a youtube viid on how to do it but VCDS Lite will not let me access that feature so...

What l really eed help on, is im sure l read a thread that you could test for boost leaks using VCDS and also you could tell if o2 sensors were faulty going by the readings of certain data. I am a complete noob and if you are wlling to help would need it explained step by step lol

So in short lol if you think you can be bothered to help and can guide me to use this software to get to the bottom of this then pls do !!

I also went into the engine selection and selected display fault codes, there were none !!

If you need any more info pls just ask

Thanks in advance

Brendan

 

[matt blowen]

Hi ya i have the same problem and i have done all of above apart from buy a maf i just cleand it, ive got a full version of vcds so ill try that when i get time and ill let you know the outcome!!

 

[bree9482]

Hi ya i have the same problem and i have done all of above apart from buy a maf i just cleand it, ive got a full version of vcds so ill try that when i get time and ill let you know the outcome!!

Awesome mate !!! im hoping tuffty or prawn etc... weigh in, they seem to know these cars inside out !!

let me know your findings mate please !! Did you watch the video ??? Are you getting the same fluttering ??

Brendan

 

[mcpickering]

I have this on my S3 sometimes it even drops dramatically to about 500 rpm and feels like it may stall then climbs to 700 or so again.
I had the TB re-aligned and it made it better for all of 2 days, then the problem came back...

 

[bree9482]

I have this on my S3 sometimes it even drops dramatically to about 500 rpm and feels like it may stall then climbs to 700 or so again.
I had the TB re-aligned and it made it better for all of 2 days, then the problem came back...

Mate it's doin ma head in !! There must be something wrong as its not right !! I really need to get the answer !!

 

[matt blowen]

Ok just tried it and it hasnt changed 1 bit. I know it was doing something because i heard it moving

 

[Lewis583]

You say you have replaced a breather pipe due to it splitting. Have you checked ALL vac pipes aswell?

There are some that fit to the underneath of the inlet manifold.

One goes to the fuel pressure regulator
The others go to N249/N75/Etc
Don't forget to inspect the brake servo line aswell.

 

[WorkInProgress]

Probably not what's wrong with yours but I had the same hunting idle problem as you. Changed my thermostat and coolant temperature sensor as part of some routine maintenance and now my idle sits perfectly. Might be worth a try on yours, parts don't cost a lot but thermostat is a pig to fit

 

[JudderMan]

but thermostat is a pig to fit

True, but you can get a small Allen key on the bolts instead of a spanner and it's a little easier. Some long needle nose pliers to turn it and a torch to see what you're doing and it's fairly easy.....I still have a scar on my arm from it though, the little ******* that it is.

 

[bree9482]

You say you have replaced a breather pipe due to it splitting. Have you checked ALL vac pipes aswell?

There are some that fit to the underneath of the inlet manifold.

One goes to the fuel pressure regulator
The others go to N249/N75/Etc
Don't forget to inspect the brake servo line aswell.

Hi mate thanks for the reply !!

I bought easy start spray and went about spraying all the vac pipes. As l did when l came to the breather hose under the inlet manifold the car started to gain revs. That was the only location that the car would gain revs. So l took the parts off to get a better look at what was goin on. There was a 2 inch hole in the breather pipe. I thought had found and solved the prob, £33 later at the stealers and yeah it has helped boost, drivability but not the idle

I could go round the hoses again but l defo only found this 1, l would like a smoke test but no one n Glasgow seems to do it !!
Someone said you can use VCDS to do it, l am a total noob on that software lol

Cheers

 

[bree9482]

Ok just tried it and it hasnt changed 1 bit. I know it was doing something because i heard it moving

Thats disapointing mate !!! WorkInProgress mentioned the coolant temp sensor, my mate had suggested this aswel !! Hmmm, maybe worth a try if its cheap !!

 

[bree9482]

Probably not what's wrong with yours but I had the same hunting idle problem as you. Changed my thermostat and coolant temperature sensor as part of some routine maintenance and now my idle sits perfectly. Might be worth a try on yours, parts don't cost a lot but thermostat is a pig to fit

Good shout mate, l have been told this before. I might have to give it a go if its cheap, if anything just to rule out !!

Cheers
Brendan

 

[Lewis583]

I would have another look at the vac pipes first before replacing anything. It will only cost you time and will definitely rule the vac pipes out then. It only takes a tiny split to affect the idle.

 

[bree9482]

So went to change the engine coolant temp sensor, Euro Car Parts in all their ****ing glory give me the wrong part. They ask you for the registration for a reason, dont they ???

Anyways rebuilt it and went to change the part at ECL. I now have correct said part so ill leave car overnight to cool and change in morning. Ill let you all know if this solves prob !!!

 

[bree9482]

So went to change the engine coolant temp sensor, Euro Car Parts in all their ****ing glory give me the wrong part. They ask you for the registration for a reason, dont they ???

Anyways rebuilt it and went to change the part at ECL. I now have correct said part so ill leave car overnight to cool and change in morning. Ill let you all know if this solves prob !!!

Well ECT sensor changed and no difference at all......

im really starting to loose my patience with this now

I found a hose that looked a little perished, sprayed some water on it but could not see any bubbles etc..
Its the first little hose on the right side of the inlet manifold. I have ordered it anyways, Glasgow Audi cant get it till Wed as their is a bank hol in England this week.

Do you think this could be perished enough to be causing a leak ???