PCV valve woes

HertS3

HertS3

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Hey guys,
After the saga with the rear diff on my previous S3 plaguing me, it seems that the S4 is (kind of) following suit.
Car was showing intermittent PCV valve malfunction error codes pretty much as soon as I bought it 3 months ago (mechanic friend scanned it 2 weeks after buying).
Car went in for recall work and the fault was identified but everything was tested and appeared to work correctly.
I took out Audi extended warranty on the day I put the deposit down on the car, though it doesn't start for 30 days. Fault date stored in the car is between purchasing the car and the warranty starting, so claim has been rejected as a pre-existing fault. I'm either very unlucky and the fault manifested itself in the uninsured period, or the fault was there and not picked up by the checks carried out by the dealer that sold me the car.

Is the PCV valve a common issue with these cars?

Quoted north of £1,200 for replacement of the valve at Audi, talking to the dealer that sold me the car on Monday.
 
Even if the paid for warranty won’t pay out it is still the dealers issue to rectify as it is so soon after purchasing
 
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Make sure you can’t the valve seperatly

had a similar issue on my non Audi that required a new cam cover and Breather set up at the main dealers at circa £1000 but after looking online it was caused by a split diaphragm and spring which can be purchased online for around £10
Took ten minutes to change and has been fine ever since
 
Unfortunately the PCV valve can be a problem with the older S4s. One common symptom is difficulty in opening the oil fill cap.
 
Notes from Audi say they found a TPI, didn't that mean it's a known issue?
 
Rich76 said:
Make sure you can’t the valve seperatly

had a similar issue on my non Audi that required a new cam cover and Breather set up at the main dealers at circa £1000 but after looking online it was caused by a split diaphragm and spring which can be purchased online for around £10
Took ten minutes to change and has been fine ever since
Click to expand...

Getting access to it on the 3.0TFSI engine is a bit involved, so that is most of why the cost is so high.
 
Dealer gave me 3 months free RAC warranty from day one so just sent them proof (Audi sent me a screenshot from ODIS) that the fault is shown 6 days into my ownership so hopefully they'll cough up £500 (that's the max per claim which should pretty much cover parts only) and I'll get an indie to do for less than £125 per hour!!
 
Update: After some 'clarification' on my part RAC will pay towards PCV valve replacement, so that's something! However, garage took the engine cover off and there's pink gunk from the thermostat on the hoses near the engine!!! Just my ****** luck!
Not too worried as Audi warranty will pick that up (they had the car two weeks ago so let them try saying it didn't happen in the policy period!!) but yet another thing going wrong, plus £100 excess I need to pay!!! (on top of the remainder of the PCV valve replacement costs as RAC's £500 will just about cover the parts so I'll have to pay for the labour)

I know this is a common Audi fault (happened on my previous S3 too), everyone kept saying to me I should've got a BMW lol
 
OK mechanic confirmed it's the bypass pipe that's leaking, not the thermostat housing
 
I'm in complete shock, the mechanic found that a pipe at the top of the engine bay (immediately visible when the cover is taken off) was disconnected. This is something to do with PCV valve, creating a vacuum etc. It being disconnected would cause readings to not make sense etc as uncontrolled air is entering the system.
If the mechanic's theory is correct that the PCV valve is fine (I've driven 3-4k miles and not had to top up any oil) then it means that my car had this pipe disconnected when I got it as fault code first logged 6 days into my ownership, not only did Audi then not pick up on this when the car was for the recall work on 13th July, but they also didn't connect it when reassembling the car, and would also mean that they didn't pick up on it recently when I brought it in again as the fault had returned and I was hoping to put it through as a warranty claim but that was rejected as fault predated the start of my policy.
For Audi's sake I hope my mechanic is wrong!!
Car will have to go in for the bypass pipe to be replaced (warranty better cough up this time!) So we'll see if by then the valve fault code returns, if it does then the valve is actually faulty
 
Indeed sir, almost as fun as the rear diff going on my previous S3 lol
Here is the offending pipe that was unplugged
 

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I would be going loopy at the original supplier and the dealership that worked on it tbh
 
Simon said:
I would be going loopy at the original supplier and the dealership that worked on it tbh
Click to expand...
Dealership that sold me the car gave me a report showing no fault codes so they won't be too interested (kept them in the loop anyway), it's Audi that would be put to shame if the fault is now resolved
 
HertS3 said:
not only did Audi then not pick up on this when the car was for the recall work on 13th July
Click to expand...
Are you referring to the 24DP rework for CREC engines to replace the LP fuel rails?
If so then please note that the procedure requires that the hose should be disconnected so that the solenoid valve N80 can be moved out of the way whilst the supercharger is removed. The procedure also states "Installation is the reverse order of removal" and "Reconnect EVAP Canister Purge Regulator Valve 1 -N80-", but relies on the tech's own competence to decide that the hose needs to be reconnected.
 
I can't quite remember, did the dealership who sold you the car do so with an outstanding safety recall? If so maybe its time to remind them that to do so is illegal, and maybe now that you have experienced such poor customer service you feel it is now your civic duty to report them.
 
Dippy said:
Are you referring to the 24DP rework for CREC engines to replace the LP fuel rails?
If so then please note that the procedure requires that the hose should be disconnected so that the solenoid valve N80 can be moved out of the way whilst the supercharger is removed. The procedure also states "Installation is the reverse order of removal" and "Reconnect EVAP Canister Purge Regulator Valve 1 -N80-", but relies on the tech's own competence to decide that the hose needs to be reconnected.
Click to expand...
Indeed, that's the recall work that was done.
If the mechanic is correct and connecting that pipe/valve sorts out my problem and the PCV valve isn't actually faulty, it means that not only was it disconnected when the car first logged the issue (23rd June, 6 days into ownership), but also not connected back after the 24DP work (maybe because it was disconnected when the car came in??? Surely not). And also not picked up over the two days the car went back in a couple of weeks ago purely for the PCV valve investigation!
 
Dippy said:
I can't quite remember, did the dealership who sold you the car do so with an outstanding safety recall? If so maybe its time to remind them that to do so is illegal, and maybe now that you have experienced such poor customer service you feel it is now your civic duty to report them.
Click to expand...
They did indeed, they weren't even aware of the recall and I pointed it out to them prior to picking the car up, they booked it in to Audi for me (which was done around a month after I picked up the car).
 
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I have a question - is this normal oil consumption after 500 miles (which is how much I've covered since an oil service in early September) or does it seem that the PCV valve is indeed malfunctioning?

Plugged in an OBD2 reader and no fault codes are showing, it's a reader I've not used before (Ancel AD410, updated online to latest version) so not sure if it would even find the PCV valve if it is present.

I had covered over 2000 miles previously and the car never asked for more oil, though admittedly I never checked the oil level.
 

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The car is playing tricks on me, tried it again with warmer engine (oil was at 88 C) and it was about a centimetre from max!
 
I saw your post from 2015, requested it on here, if it's reasonable I'll get it posted :)
 
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@HertS3 Just for your info. the PCV valve is a mechanical oil seperator and it has no electrical connection. It is made from plastic and has oil vapour (crankcase ventilation) and water running through it (seperately) which can lead to leaks either way or out of the unit, if it cracks.
The main component is a spring and diaphragm which can fail. These component parts are available for a cheaper fix, but by the time you get to the unit it seems prudent to replace it entirely.
eg here............

PCV
 
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Thanks, some of that info I knew and some I didn't. My mechanic actually showed me a failed diaphragm from a 2.0 TFSI Audi engine, failed around similar mileage to mine (50k), which he said is very poor indeed. Should last til around 100k. Issue was that the 2 litre PCV is £80 whereas the S4 is £500 excluding labour!
I'm trying to establish whether the valve is indeed faulty, Audi concluded this after having the car twice (all connected pipework etc was apparently fine), but the fact that the N-80 valve (or whatever it's called, see above) was unplugged when my mechanic took the cover is worrying as Audi were the last to have the car before this, for 2 days! It's a long-shot but my mechanic reckons that if this valve was unplugged the whole time then the car would bring up the PCV valve fault that we've been seeing, plus he says the engine sounds fine now.

I've not had excessive oil consumption so far, apparently a tell-tale sign of a failed valve is having to top up a litre every 1000 miles. Done 500 miles since oil service and it's around 10 - 30% down the 'dipstick' (getting a real one lol).

By the time someone gets down to the valve to inspect it, you might as well change it (as you say), plus I've got RAC warranty poised to pay £500 towards it anyway (if it is faulty) as the fault occurred within my free warranty period given with the car, so that would cover the parts (though labour would be at my cost).
Driving it a while longer to see whether excessive oil consumption occurs and/or the PCV fault rear its ugly head to determine whether the valve is indeed up the creek.

Fun and games!
 
FYI I have that oil level measurement shown on in one of the lists of my FIS-Control MMI screens. Whilst driving it bounces around ridiculously. The oil definitely needs to be hot and settled for it to be considered accurate. If you can't afford to wait long enough for it to settle then a dipstick is indeed to be recommended.

BTW although very rare I believe there have been cases of excessive oil consumption due to piston ring issues on the 3.0 TFSI. Likely not the same reason as plagued a range of 2.0 TFSI engines - probably early run-in problems instead.
 
Interesting, though my car logged PCV valve malfunction faults since 6 days after ownership at the end of June, so if there is excessive oil consumption (no signs of it so far) then it seems to be related to the PCV valve.
 
Just an update on this, car went in for MOT and service and all fine but the ****** PCV error code has reared its ugly head again.
Going to confirm with RAC Warranty (got 3 months free when I bought the car and according to Audi's system the fault began 6 days into ownership) that will pay towards it (max payout £500 which will cover just the parts!) as they had confirmed this back in October but I didn't get the work done as the fault had disappeared and the mechanic and I were hoping that it wouldn't return.
D'oh!!!
 
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