Strange Behavior

[fly300kts]

Hi Guys,

Need your opinion on this one. Does anyone have seen this?

Video

When the car is cold, the RPM is surging +/- 500.
I did align the Throttle Body with Wag Com but not changes.
Any idea?

Ding Ding!!!
Problem found: For those of you facing the same issue, read this: http://www.audizine.com/forum/showth...d-the-problem-!!!
I can't really tell at 100% this was the root cause since I also changed at the same time the plastic hose going from the PCV to the intake. I only changed it because he was leaking. If your does not leak, then check the thread

[AWDTURBO]

I have never seen this happen, and i guess you are not throwing any codes?

[2007B7cabrio]

Hi Guys,

Need your opinion on this one. Does anyone have seen this?

Video

When the car is cold, the RPM is surging +/- 500.
I did align the Throttle Body with Wag Com but not changes.
Any idea?

Thx

Phil

I have +/- 200rpm, during constant speed (light trottle), but haven't look into it yet as it disappears after the engine gets warm, I however noticed that it was worse before I replaced my DV as the old one was toast, literally missing a piece of the membrane.

Mine is a Tip so that could be the difference, I guess that S FL cars does not like the cold weather

[fly300kts]

I have never seen this happen, and i guess you are not throwing any codes?

No, no code

Phil

[thenofjboy]

I’ve seen this before with idling a little higher when cold but not the surging your seeing. How long does this last if you just let it sit there?

If you let it warm up for 5 min, give it some gas, does the idle settle down & the surging go away? Usually this for works for the idle portion but I’m not sure about the surging.

Might try to cleaning the TB, that’s been known smooth out idles

[fly300kts]

If I let the car at idle for 10 mn, the idle is steady.
I only see the issue during the first 10 mn of the drive, morning or afternoon
The TB was cleaned 3 weeks ago. I might have to replace the TB but would like to be sure

Phil

[bengtc]

What year is your car, I had a 2005.5 and my car also did the exact same thing, I have a 2008 now and it does not. Maybe the ecu software was updated since the early b7's?

[fly300kts]

What year is your car, I had a 2005.5 and my car also did the exact same thing, I have a 2008 now and it does not. Maybe the ecu software was updated since the early b7's?

Yes, 2005.5 here

Phil

[BigRob]

I recently noticed the same problem with my 2007 A4. It only happens when the engine is cold and when I am holding a constant speed, like driving through my neighborhood doing 25mph. At first I thought I might have a vacuum leak but I have no codes and it goes away once I have been driving for like 10 minutes also. The engine surges just about as much as yours Phil. Let me know what you find out as I would like to fix this issue also.

[fly300kts]

I recently noticed the same problem with my 2007 A4. It only happens when the engine is cold and when I am holding a constant speed, like driving through my neighborhood doing 25mph. At first I thought I might have a vacuum leak but I have no codes and it goes away once I have been driving for like 10 minutes also. The engine surges just about as much as yours Phil. Let me know what you find out as I would like to fix this issue also.

Well, I will.....If I find out
I even played with the Cruise and the fluctuations are the same

Phil

[esm]

The exact same thing happens to me when cold (really cold in Chicago), and usually when at constant speed near 1800-2200RPM. Once the car is warm, goes away completely. This usually does not happen during the warmer months. The car is a 2005.5, APR stage 1, stasis exhaust, quattro, tip.

I have +/- 200rpm, during constant speed (light trottle), but haven't look into it yet as it disappears after the engine gets warm, I however noticed that it was worse before I replaced my DV as the old one was toast, literally missing a piece of the membrane.

Mine is a Tip so that could be the difference, I guess that S FL cars does not like the cold weather

[naiku]

I have had the same thing since owning the car, fluctuates when cold, goes away once warmed up, pretty sure it has come up numerous times on here before and is considering normal.

[AudiTFSI3o3]

I have had the same thing since owning the car, fluctuates when cold, goes away once warmed up, pretty sure it has come up numerous times on here before and is considering normal.

x2

[baldy]

I recently noticed the same problem with my 2007 A4. It only happens when the engine is cold and when I am holding a constant speed, like driving through my neighborhood doing 25mph. At first I thought I might have a vacuum leak but I have no codes and it goes away once I have been driving for like 10 minutes also. The engine surges just about as much as yours Phil. Let me know what you find out as I would like to fix this issue also.

X2 Mine does the same thing when it's cold out if i don't let her warm up long enough...

[Coderedpl]

I have had the same thing since owning the car, fluctuates when cold, goes away once warmed up, pretty sure it has come up numerous times on here before and is considering normal.

I must say
x3

I get the same thing in the winter more than the summer. Has happened a few times during warm months but not much. Never bothered me enough since its only for the first few minutes and thats it.

[brownishwater]

Mine '06 did the same thing until I installed the stage II PCV fix. Not sure if that had anything to do with it or not, but it doesn't idle like that anymore.

[joeygriebel]

I have an '07 and experience the same, 200 rpm jump going about 20 through the neighborhood at cold starts. I don't get it in the evening on the way home from work, only in the mornings. Subscribed to what you find out is the cause!

[kwik_shift]

any updates?? i have a friend with a b7 that has the same idling issue. Except he was having issues getting the car to go over 20-25mph. stealership said possible a bad injector. Reflashed/rebooted the ECU and it's normal for now....

[fly300kts]

any updates?? i have a friend with a b7 that has the same idling issue. Except he was having issues getting the car to go over 20-25mph. stealership said possible a bad injector. Reflashed/rebooted the ECU and it's normal for now....

Not really. Decided to leave with it as long as it does not get worse

Phil

[Slovak84]

I have a 2008 and ever since the temperature has dropped my car has been doing the same, for the first 10 minutes of driving. When the enginge reaches the normal operating temp range the minor surging lasts like another 3 minutes then goes away. I have owned the car over a year and a half and it just started doing this, this winter. I am also however running the seat warmers on 3 (both seats) and heat on 72 (Auto) maybe this is taking extra power away from the engine and causing the surges?

[fly300kts]

No Electrical seat on mine and same behavior. Are you chipped?

Phil

[airbornerifleman]

I recently noticed the same problem with my 2007 A4. It only happens when the engine is cold and when I am holding a constant speed, like driving through my neighborhood doing 25mph. At first I thought I might have a vacuum leak but I have no codes and it goes away once I have been driving for like 10 minutes also. The engine surges just about as much as yours Phil. Let me know what you find out as I would like to fix this issue also.

Same here. I noticed it first last winter. The "surging" is not violent by any means.

I'm APR chipped, but it happens in stock or 91/93 mode.

[72mako]

Mine does it too, but worse if I sit on cruise at 45mph driving to the highway. If I take it off cruise it's not quite as noticeable and as others have said, it goes away once the car is warmed up. It's been like that as long as I've owned it, so about 99k miles. I couldn't really tell you if it does it in stock mode because I don't use it but it does it with my APR 93.

nick

[pucher]

Looks to me like the torque convertor is having some slipping issues while it is cold and in the "control" phase. If you have a VAG you should be able to watch the torque values in the TCM showing torque convertor slippage and control.

[Slovak84]

I also run APR flash 93. I have multiple programs installed, but have been using 93 octane for over a year and a half. It just started doing this since last month or so...

[fly300kts]

SOLUTION POSTED !!!!!

Phil

[airbornerifleman]

Just so I understand correctly. There should be no play on the hose that is connected to the vacuum pump? I have a little bit of play when its cold. Is that the reason why the RPM surges when the engine is still cold?

I know you fixed the issue by applying some JB weld but what is the OEM repair and DIY and PN for this issue?
How do you align the TB with Vag-Com?

[fly300kts]

Just so I understand correctly. There should be no play on the hose that is connected to the vacuum pump? I have a little bit of play when its cold. Is that the reason why the RPM surges when the engine is still cold?

I know you fixed the issue by applying some JB weld but what is the OEM repair and DIY and PN for this issue?
How do you align the TB with Vag-Com?

There should be no play on this tube
Is this the reason why? Can't certify it because due to a leak, I also replaced the tube from PCV to intake. Drove again this morning, no fluctuation.
OEM repair = Replace the pump. No WAY

Alignment procedure with VAGCOM:

[Select]
[01 - Engine]
[Basic Settings - 04]
Group 060
[Go!]
It should say "Basic Settings: OFF" on the top of your screen.
Click [ON/OFF/Next] to turn on Basic Settings.
It should now say "Basic Settings: ON" on the top of your screen.
Once you do this you will see the top right display say ADP RUN. The TB adaptation is being done as soon as you switched basic settings on. You will see the values change and hear the TB cycle for the first few seconds then it will stop. Leave it in Basic Settings for about 30 seconds.
Click [ON/OFF/Next] to turn off Basic Settings.
It should now say "Basic Settings: OFF" on the top of your screen
Click the [Done, Go Back] button and you're all set.

Be sure not to touch the accelerator and make sure the engine is NOT running when you do this!

[airbornerifleman]

Thank you sir!

[fly300kts]

Thank you sir!

Your welcome Sir

phil

[esm]

The exact same thing happens to me when cold (really cold in Chicago), and usually when at constant speed near 1800-2200RPM. Once the car is warm, goes away completely. This usually does not happen during the warmer months. The car is a 2005.5, APR stage 1, stasis exhaust, quattro, tip.

Update: Got my car back from the dealership today after a minor checkup. They found fault code P0642 and replaced the "intake flap motor." Whatever that it. Does that sound right to anyone?

[Inked]

Update: Got my car back from the dealership today after a minor checkup. They found fault code P0642 and replaced the "intake flap motor." Whatever that it. Does that sound right to anyone?

I thought the intake flap motor was the n80 valve?.....search n80 valve...

[B72.0T]

I thought the intake flap motor was the n80 valve?.....search n80 valve...

Huh??? In no way are those two the same thing buddy.

[Leo14]

Huh??? In no way are those two the same thing buddy.

Lol x2.. IIRC the n80 is the purge valve

[Inked]

Lol x2.. IIRC the n80 is the purge valve

lol haha my bad....not sure where I got that from, sometimes all the info on here just 'meshes' together when you are reading 1000 posts at a time LOL

[Leo14]

lol haha my bad....not sure where I got that from, sometimes all the info on here just 'meshes' together when you are reading 1000 posts at a time LOL

Lol I know exactly what you mean

[rune]

I got some codes on my car this week :
Definition not found 05634,08200,12600. I checked out and it looks like there can be a issue with the intake manifold flap motor/sensor. So maybe the throttle body can cause RPM problems ?
I have cleared the codes and seem not to come back(still have RPM jumps). but, can the throttle body have a fault without throwing codes?

Here is a video of my problem taken by wildcat.

http://www.youtube.com/watch?v=kdmL68HIBVE

Anyone ?

[fly300kts]

I got some codes on my car this week :
Definition not found 05634,08200,12600. I checked out and it looks like there can be a issue with the intake manifold flap motor/sensor. So maybe the throttle body can cause RPM problems ?
I have cleared the codes and seem not to come back(still have RPM jumps). but, can the throttle body have a fault without throwing codes?

Here is a video of my problem taken by wildcat.

http://www.youtube.com/watch?v=kdmL68HIBVE

Anyone ?

Regarding the throtle body, perform a complete aligment with the Vag com cable
I would be really to bet that your problems are coming from the tranny fluid level when the car is cold. I had the exact same behavior!!

phil

[rune]

Regarding the throtle body, perform a complete aligment with the Vag com cable
I would be really to bet that your problems are coming from the tranny fluid level when the car is cold. I had the exact same behavior!!

phil

Today i started the car, and let it warm up to 90 Celsius(working temp) before i drove away. Then i had NO RPM variation at all.
I have an appointment with a dealer on tuesday to check my tranny oil level again. And also change fuel filter.I also have bought new DV,PCV,N249 valve but i will begin with oil level and see what happens and do step by step changing parts. First see how the car is after checking tranny.
I have a strong feeling about the oil level can be wrong.

Phil, Do you remeber how much oil you were missing when you had this problem ?

thanks

[fly300kts]

Today i started the car, and let it warm up to 90 Celsius(working temp) before i drove away. Then i had NO RPM variation at all.
I have an appointment with a dealer on tuesday to check my tranny oil level again. And also change fuel filter.I also have bought new DV,PCV,N249 valve but i will begin with oil level and see what happens and do step by step changing parts. First see how the car is after checking tranny.
I have a strong feeling about the oil level can be wrong.

Phil, Do you remeber how much oil you were missing when you had this problem ?

thanks

Well, I don't know exactly since I did not measured the amount of drained oil to compared it to the amount of oil added but I am almost sure that it doesn't need a lot to trigger the problem
Are you goin going to leave the car overnight at theDealer? Remember, oil level check has to be done when the ATF temp is below 40 degrees.Since my oil replacement, 3 weeks ago, fluctuations are totally gone

phil