S3 revving by itself, pcv changed what next ?

I'm going to get it booked in and get it looked at again. Probably ask them to have a look at throttle body. And air intake temperature sensor and even coolant temp sensor as they seem to be a weak point and it's on the list of possible causes for my fault code.
 
  • Like
Reactions: Audiabc7
R222cet said:
I'm going to get it booked in and get it looked at again. Probably ask them to have a look at throttle body. And air intake temperature sensor and even coolant temp sensor as they seem to be a weak point and it's on the list of possible causes for my fault code.
Click to expand...
Mind now when you get to the bottom off it and hopefully fixed share with us please as this thread has been qorth following cheers
 
Replacement dipstick arrived and installed, cleaned the old orange one and it totally disintegrated in my hand, not impressed with Audi, clearly this alone should be a recall item. But will wait and see what happens next.
 
I never knew it was such a bad part. I'm going to get a new 1 myself just incase.

On the revving situation this is the first day I can remember it not doing it all day 16 mile round trip to work and nipped to asda after that didn't do it once :s I even tried to do haha
 
Ok so here is the update, replaced the Orange DipStick with Yellow one and it's made a significant difference, now after 5 days of testing regardless of the weather the rev counter hunts up to 1800 RPM and then settles back down to 800 RPM just once during each trip, be it 10 miles, 20 miles or 50 miles. So while it's a result it's not fixed. Going to see what happens over the next few weeks before I splash out on more diagnostics.
 
Mine felt abit better over the last couple of days after I was told the intake pipes had been reattached. But today it's been hunting a lot probably due to the weather 14-15 degrees here.
 
garethrees said:
Ok so here is the update, replaced the Orange DipStick with Yellow one and it's made a significant difference, now after 5 days of testing regardless of the weather the rev counter hunts up to 1800 RPM and then settles back down to 800 RPM just once during each trip, be it 10 miles, 20 miles or 50 miles. So while it's a result it's not fixed. Going to see what happens over the next few weeks before I splash out on more diagnostics.
Click to expand...

Yesterday started hunting again 10 times :( then stopped and could not reproduce. Strange as it was only about 10 mins into the 8 mile run. Outside temp was 15c just in case there is a pattern.
 
garethrees said:
Yesterday started hunting again 10 times :( then stopped and could not reproduce. Strange as it was only about 10 mins into the 8 mile run. Outside temp was 15c just in case there is a pattern.
Click to expand...
The next day, same trip, same weather and nothing.. not a blip.
 
garethrees said:
The next day, same trip, same weather and nothing.. not a blip.
Click to expand...
Sounds like an intermittent sensor problem, throttle position sensor would be my best guess (integrated into the throttle body) if pcv and vacuum leaks have been ruled out.

Tried my best diagnosing with vcds, every sensor reading on the throttle body looked perfect, no issues in the output tests and no fault codes whatsoever. Will be trying the maf clean as a last attempt, if that doesn't help then I'm done diagnosing this for a while and will just enjoy the car as it's not a huge deal and it still drives very good.
 
I had mine in at awesome yesterday, smoke tested it was all fine but as he plugged the diagnostics in it wouldn't let him reset anything timing, fueling etc so he swapped my maf sensor for another 1 out of a customers car and he could then reset everything so he thought it was my maf, Told me to bring it back on Saturday and let him know how it is. Unfortunately it's still doing it tho really bad yesterday as it was 22. He also said if the clips on the pcv arent great when the plastic warms up it expands and allows more of a vaccum.
So still no fix I'll report back on Saturday getting abit sick of it now !
 
Oh how could I forget he said the car feels like it's been mapped which is news to me. Would a bad map cause something like this ?
It's just the fact it's doing it when it's warm is confusing me
 
R222cet said:
Oh how could I forget he said the car feels like it's been mapped which is news to me. Would a bad map cause something like this ?
It's just the fact it's doing it when it's warm is confusing me
Click to expand...
Thanks for the updates everyone! I have actually been thinking about the bad/generic map theory as well, as I have a generic stage 1 map on mine. When combined with other tuning parts like an aftermarket intake some cars can get misfires etc, while others run perfectly fine. Although I can't really see how a map alone could make the revs hunt/rise.

Does your brake pedal become hard after the car has been sitting for a few hours? Mine does, and this leads me to believe there could be a small vacuum leak somewhere... Other cars I've tested can hold brake vacuum for days and pedal only becomes hard when you pump it a few times...
 
No I can't say it does I was sure it had something to do with a vacuum but the smoke test tells me otherwise unless it's the throttle body. Anyway I've gotta go back on Saturday to pick my new maf up as I'm using a second hand 1 ATM and then we will take it from there see what he suggests to do next
 
Had my new maf fitted today the car feels a lot better ! It's still hunts slightly on the odd occasion but the ecu will be self learning for around 300-400 miles so hopefully it will eventually stop doing it all together. He also said the the maf failing is very UNCOMMON to fail on these cars

I'll report back again after I've put some miles on. Hope this helps the few that are having the same problem
 
  • Like
Reactions: Audiabc7 and HHS3
R222cet said:
Had my new maf fitted today the car feels a lot better ! It's still hunts slightly on the odd occasion but the ecu will be self learning for around 300-400 miles so hopefully it will eventually stop doing it all together. He also said the the maf failing is very UNCOMMON to fail on these cars

I'll report back again after I've put some miles on. Hope this helps the few that are having the same problem
Click to expand...
They fail a lot if you fit cotton air filters like K&N and clean and re oil them, the oil *****them up.
 
That may have been the case as I bought the car thinking it was a well looked after standard car with only 39k but a mechanic at awesome seems to think it's been mapped so it probably had 1 on before
 
audismart said:
They fail a lot if you fit cotton air filters like K&N and clean and re oil them, the oil *****them up.
Click to expand...
So maybe a good idea to clean the maf more often then, thanks for the heads-up!

Cleaned my maf today, no difference in the rpm behavior, but noticed the brake vacuum holds much better since I replaced the dipstick. So definitely one vacuum leak fixed! Hopefully things improve further when the ecu adapts...
 
  • Like
Reactions: audismart
Audiabc7 said:
So maybe a good idea to clean the maf more often then, thanks for the heads-up!

Cleaned my maf today, no difference in the rpm behavior, but noticed the brake vacuum holds much better since I replaced the dipstick. So definitely one vacuum leak fixed! Hopefully things improve further when the ecu adapts...
Click to expand...
Or fit a pipercross dry filter.
 
Just to provide and update, replaced dipstick on May 15, since then one instance of repeating hunting, then it would seem once a day it hunts just once, but you only notice it on short trips when you stop at lights, regardless of weather, once it's hunted once it does not occur again that day. Feels like the ECU is re-learning after the dipstick, so have setup a spreadsheet to record the trips/weather and revving to monitor. Not sure this is the same as others but wanted to share what I have learned.
 
I might do the same as i got my new stick from audi last week but not been out in car much
 
Guys i think this is related to the bad throttle body sensor. But since it's integrated into throttle body the whole thing needs to be changed. My car does it to, today it cut off coming to a stop. Tried throttle body adaptation and it didn't help. So got to source another one and see if it will fix this issue.
 
So after a new maf and the car being perfect for a week and 250 miles the car is back to its aweful self today this had made me even more baffled it's driving me mad ! To make it worse as I thought the car was fine I bought myself a revo intake so now Ive no spare cash either
 
R222cet said:
So after a new maf and the car being perfect for a week and 250 miles the car is back to its aweful self today this had made me even more baffled it's driving me mad ! To make it worse as I thought the car was fine I bought myself a revo intake so now Ive no spare cash either
Click to expand...

That sucks to hear, I'm pretty much in the same boat as the brake vacuum behavior is back again. Might try to build my own smoke tester when I have time just to rule out any vacuum leaks once and for all. Other than that I think the only option left is to bite the bullet and get a new throttle body, kinda sucks as I've just had the entire manifold in pieces...

S. said:
Guys i think this is related to the bad throttle body sensor. But since it's integrated into throttle body the whole thing needs to be changed. My car does it to, today it cut off coming to a stop. Tried throttle body adaptation and it didn't help. So got to source another one and see if it will fix this issue.
Click to expand...

Do you have a lightweight flywheel as well? I think that might make the engine more prone to stalling if there is an issue to begin with. Never noticed rpm's dropping below idle before the flywheel was fitted.
 
Yes, i do have smf.
Just to update, had throttle body realigned with vcds and since then it seems much better.
 
audi upgrades
My next move is to have a look at the TB I just can't see it being that tho. I had a new maf and reset the cars ecu I could tell the car was learning as it seemed to fade out the hunting. Then it was perfect for exactly 7 days and around 350 miles and it's suddenly back to hunting 90% of the time when I pull up.

I'm booked in for a RR day to see if that has anything to do with it. If it is maybe timing and fueling isn't set right. Wishful thinking
 
Any more on this issue as I'm in the same situation. I've changed the pcv and n80 with no joy
 
Since changing the broken dipstick and traveling about 400 miles I've seen an improvement but not resolved, so I started logging temp verses revving and my logs have shown that if the outside temp is lower than 19c it happens more frequently sometimes revving about 5-20 times and if it's above 19c it rarely happens and if it does only once. I have it booked in for a Throttle Body reset and diagnostic next week.
 
I was beginning to think it was the coolant temp sensor. Finally found a air leak so hopefully thats going to be the end of that
 
Got mine in this week and they smoke tested it found that there was a slight leak coming from the PCV, it's now been replaced (not expensive to do) and I've driven about 200 miles in various temps from 15c to 28c and no sign of the revving.... here is hoping that it's fixed.
 
Great news. I also have had some progress found a split pipe so it's going in on Tuesday fingers crossed
 
  • Like
Reactions: HHS3 and garethrees
garethrees said:
Just to provide and update, replaced dipstick on May 15, since then one instance of repeating hunting, then it would seem once a day it hunts just once, but you only notice it on short trips when you stop at lights, regardless of weather, once it's hunted once it does not occur again that day. Feels like the ECU is re-learning after the dipstick, so have setup a spreadsheet to record the trips/weather and revving to monitor. Not sure this is the same as others but wanted to share what I have learned.
Click to expand...
The PCV is always the first port of call.
 
  • Like
Reactions: garethrees
R222cet said:
Hi guys seems an awful lot of people have this problem but it seems to be fixed with changing the pcv. I've done this today replacing the pcv and gasket and I still have the problem :/ So what's next to check ?
The car seems a little rough on idle and when I'm coasting up to the lights and come to a stop the revs Will rise to around 1.3k and go back down and on the odd occasion it will do this 3 times in a row ! Only seems to do it when engine is up temp aswell.
It's driving me mad now any help is appreciated
Click to expand...

Mine is the same changed pvc still happens strange it only dose it when my car is up to temps... one off the most annoying thing about the a3.... iv neva seen enyone get to the bottom off this matter but heard it could be somthing to do with the cluch peddle mechanism.
 
Get some maf or electrical cleaner and drop out the maf and air intake temp sensor and give a good spray. you'll be amazed at how dirty they get. Be gentle with them though as they are delicate.
 
I'will be changing throttle body and clutch possition sensor while the car is in garage again. Will see if that cures rev issues.
 
I think its the clutch possition sensor as i had my throttel body done i cant locate it tho enybody know where it is????? Dont think its maf but will take your advice and cleen it all up better safe than sorry ey
 
  • Like
Reactions: audismart
I got this sorted months ago it turned out to be a split pipe (can’t remember which) It Had a smoke test and couldn’t find the leak anywhere
 
Audiabc7 said:
As the issue seems to be somewhat boost related I tried switching back to the oem rev G diverter valve instead of the dv+. Again no difference in the idle behavior, but noticed the car boosted way harder with the rev G valve fitted! Really surprised as the dv+ is supposed to be the best dv upgrade available...
Click to expand...
The DV+ is a good mod. Did you buy secondhand as GFB supplied a modified plunger and stronger spring for K04 engined cars as they had issues with them. The modified plunger is black.
 
  • Like
Reactions: HHS3
You must log in or register to reply here.

Similar threads

Alfieaudi
Car revving itself
Replies
5
Views
1K
ch1z64
ch1z64
Alfieaudi
  • Ask a Question
Car revving itself
Replies
1
Views
809
S3AMJ
S3AMJ
alwaysconfusedaf
Car is revving itself
Replies
21
Views
4K
Troubs12
T
A
Car revving itself on idle ?
Replies
21
Views
39K
Raheem
R
M
S3 2.0 tfsi revving at idle on its own? not pcv changed it already
Replies
6
Views
2K
S38P--Joe
S
Top
Back