misfire update

[approved]

right then, spent an hour with the tech, who was a nice enough chap although a bit green when it comes to rs...got it to stutter a few times, and he went away to do the air box flap test...came back in, looked at the service advisor and said he would need the car for a day to check the flap and vacuums etc..

i asked him what the test showed and he said the flap was moving..

fair dinkum i thought so i also asked him to show me where the flap was etc, so he came out and opened the airbox for me and showed me the flap and with the engine off, it was fully open.

i said i thought it should be shut and only open under load, and he said he wasnt sure...i asked him if it rotated the full 90 degress when tested and he said no, it did move, but not much.

he went back inside, and i thought i'm going to book it in so followed him in, and overheard him talking to the service advisor and the service manager...he was talking about the flap and the manager said 'just charge him'

i interupted them, and was about to book it in and then thought i was about to be had over, so said i'd come back to them...

the advisor was saying it wouldnt be covered by the warranty, which tallied nicely with the manager saying just charge him.

so

a/ is this covered by warranty?
b/ i got home and put my hand in and the flap is still open, and very stiff...can i squirt some wd40 in there and work in free? would this cause any damage?

come back to me..i feel i'm gettting somewhere, but dont want my pants ripping down to the tune of 110 per hour to do something i can effectively do myself..bearing in mind solenoid appears to be still working, the flap is just stiff...

[Ice_Coffee]

of course it's covered by warranty! don't squirt anything anywhere let them fix it, and involve Audi UK if you have to.

[neckarsulm]

Have you seen my guide Jonathon?
http://www.volkswizard.co.uk/airbox.htm
At the end is video of how a working flap and defective flap should look
IIRC the flap should be closed when engine off
Mine was stuck open like yours and moved a tiny bit.
I fixed mine by stripping it down and filing a bit off the flap as it was jamming in the body of the airbox.
It should be under warranty especially if Audi Approved Used as others have had it replaced inc Terry at Ipswich Audi

Mine was driving fine then though, no misfires, nothing.

Have you checked your exhaust flaps work OK as this is as good a test of vacuum system being OK as the airbox flap?

Until you see it working fully I wouldn't assume solenoid is OK but it probably is .

[approved]

exhaust flaps work fine..

can i just squirt some wd40 in there and work it loose with my hand in there?

[sonny]

can i just squirt some wd40 in there and work it loose with my hand in there?

You can do, I have done this. BUT, DONT, as It may invalid any future warranty work that may have to be carried out. It may not just be the flap thats causing the problem.

[neckarsulm]

So to summarise, the vacuum system seems to be OK, you may have a local issue with the airbox flap which wouldn't cause the stutter but you still have a stutter.

We know the vacuum system works OK but could there be an issue with the vacuum operation of the intake manifold?

Surely this would log a fault?
Did Audi run a fault code scan?

[scottie1979]

So long as they replace parts you will be ok on warranty - if it is just lubrication then no warranty claim (extended warranty).

That is my experience anyway

[Terry1948]

I watched the tech carry out the power flap test he was quite happy to do this and he said that he thought the solenoid was not working and would put a vacuum gauge on the system to check for losses.It was both that had failed although the flap would open when the solenoid was replaced it would not close. It is my oppinion that the manifold flaps were opening and closing due to a vacuum loss and then the vacuum was building up again. The work was done under warranty but the tech did say that they only get paid for a set rate that does not pay for all the labour.

[approved]

So to summarise, the vacuum system seems to be OK, you may have a local issue with the airbox flap which wouldn't cause the stutter but you still have a stutter.

We know the vacuum system works OK but could there be an issue with the vacuum operation of the intake manifold?

Surely this would log a fault?
Did Audi run a fault code scan?

no fault codes found.

i havd a replacement inlet manifold not that long ago due to flaps not opening and closing properly. ran fine for a couple of weeks and now its got the flat spots at the higher rev range.

they did the airbox flap test today and thats when we discovered its stuck open...now i recall you saying something on another thread..the airbox flap diy one..reference the flap being stuck open all the time not causing any permanent damage, but the possibility of it retarding the timing at higher rpm?

http://www.rs246.com/index.php?name=PNp ... c&p=409762

i'm going to get them to look at the rest of the vacuum system and just make sure that everything is cool and the gang...

[neckarsulm]

now i recall you saying something on another thread..the airbox flap diy one..reference the flap being stuck open all the time not causing any permanent damage, but the possibility of it retarding the timing at higher rpm?

http://www.rs246.com/index.php?name=PNp ... p;p=409762

..forgot I even said that but yes, it's all about the intake air temperatures, however mine did not flat spot in the summer when IATs were much higher. Yes the timing may have been less than perfect for me then but no way would it flat spot, just feel a little less sharp.

My money is on something to do with the previous manifold replacement like an air leak, it's only been 5 weeks since it was fitted so forget the flap specifics, just tell them to fix it or go elsewhere

[P_G]

So to summarise, the vacuum system seems to be OK, you may have a local issue with the airbox flap which wouldn't cause the stutter but you still have a stutter.

We know the vacuum system works OK but could there be an issue with the vacuum operation of the intake manifold?

Surely this would log a fault?
Did Audi run a fault code scan?

no fault codes found.

i havd a replacement inlet manifold not that long ago due to flaps not opening and closing properly. ran fine for a couple of weeks and now its got the flat spots at the higher rev range.

they did the airbox flap test today and thats when we discovered its stuck open...now i recall you saying something on another thread..the airbox flap diy one..reference the flap being stuck open all the time not causing any permanent damage, but the possibility of it retarding the timing at higher rpm?

http://www.rs246.com/index.php?name=PNp ... c&p=409762

i'm going to get them to look at the rest of the vacuum system and just make sure that everything is cool and the gang...

Hmm, replacememt IM; kink in the vacuum pipe under it when refitting leading to the airbox falp but not the exhaust valves branch?

[Dom81]

Mine was stuck open when I hooked up and did the test a few months ago, although I feared the same having logged some slow runs. I had a fiddle (technical term) and hopefully loosened things up, but will check again soon. If it's still sticking I'll probably replace the lower airbox next time it's at MRC, as neckarsum / Arthur's filing solution is beyond my comfort zone (and hard to do in the street!)

[ChrisCSL]

Interesting reading.
I ran my fuel down today and filled up again incase my problem is caused by bad fuel. No problems in 2nd & 3rd gear accelerating. Unfortunately with so much traffic in rush hour I couldn't test in higher gears. Will do tomorrow as I've got a long run
If I still have the problem I'm not sure to take it to Camberley Audi or go MRC to fix and get a valve clean etc (No warranty for me).

[approved]

shame i dont gave a knowledgable and enthusiastic dealer up here....

manchester have really dissappointed me with there lack of knowledge and their mercenary attitude to costing stuff.

tempted to cut my losses and get rid.

[neckarsulm]

Hmm, replacememt IM; kink in the vacuum pipe under it when refitting leading to the airbox falp but not the exhaust valves branch?

exactly what I was thinking

Come on Jonathon, chin up, keep the faith!
Have a day out somewhere nice and try another centre, Camberley (200 miles) , Halesowen (90 miles) , Neckarsulm works service (800 miles)!