Help please...'02 A4 2.0FSI Low idle speed/lumpy missfire and sometimes hard to start

[j3aay]

Hi Guys,

Just bought the above car and it runs OK. However, sometimes it takes a couple trys to start, or it will start and cut out then require a bit of accelerator to get it to start.

When its started it doesn't stall but does run a little lumpy with the odd splutter...a definate missfire.

It drives great with what seems like no impact on power or fuel consumption (but then i am coming from a re-mapped BMW 330d so it's gonna feel a lot less powerful).

The car has FSH and isn't due a service for 7k yet. I was aware it went into a garage in November due to 'poor running' (seller told me and i have the reciept in hand). There it had a new MAF and Throttle sensor.

I also found a reciept for a few months back for a 'nocks' sensor, i assume this should say NOx sensor which i have read a faulty one could show these symptoms. But then it has been replaced.

I have no warning lights or other complaints...just the lumpyness and occasional reluctancy to start.

Anyone help at all?

Having just bought it i can't really afford to get it looked at (at least until its a real problem...it does drive fine when actually on the road at the moment).

Thanks guys!

 

[Digger1]

I have the same engine,,, My money's on it being one of the coil-packs...

 

[j3aay]

Have you had this problem with yours then? Where are the coilpacks? Is that the red boxes on the top of the engine?

Sorry for the ignorance, i have not got much experience of these cars.

Cheers

 

[Digger1]

Have you had this problem with yours then? Where are the coilpacks? Is that the red boxes on the top of the engine?

Sorry for the ignorance, i have not got much experience of these cars.

Cheers

Yes it's very common, a lot of members inc; myself carry a spare,,, the coil pack is what connects to each plug
they just become weak,, the way to check is lift the first one of the plug to see if it runS worse if it does then it's NOT! that one,replace and try the next, and work your way back, if you remove one and start the car it runs as you've described, then it's that one you need to replace there about £35 from GSF...

 

[j3aay]

That is great, i will try that tomorrow.

Cheers, Jay

 

[j3aay]

Just another quickie, do i just pull them upwards or do i need to un-clip them or something?

Don't suppose there's a how to?

Thanks again.http://www.vwaudiforum.co.uk/forum/editpost.php?do=editpost&p=601803

 

[Digger1]

Undo the two screws that hold down the complete coil-pack section and lift each one up with a screw-driver !

 

[CHRIS555]

Possibly the Crankcase Breather Valve - extremely common problem - the main symptom is having a low/bobbly idle (600-900) but being ok when in motion.

 

[CHRIS555]

Take a look at this.......

http://www.audi-sport.net/vb/a4-a4-...nning-lean-bad-idle-problems-after-remap.html

 

[CHRIS555]

Also, the garages always tend to look at things like "cleaning the throttle body", coilpacks and MAFS first - this is because some use a check list of "popular" issues and people have been known to spend hundreds to then find out it was just a DIY £6 part!

 

[j3aay]

Well today I bought a coil pack from GSF... tried it in each plug and no change. I will try and find this breather now and try the 'pinch the hose' test.

Hopefully I can find the breather!

Thanks

*EDIT*

I can't seem to find the breather. Mine is the 2.0FSI non-turbo...anyone know where it is? I found a T piece join up close to the back on the bay by the inlet manifold but couldn't see a breather/valve.

I did however find this hose (see pic below) hanging loose in under the ABS box, on the R/H of the engine bay. Any ideas where it's from?

Thanks lads.

 

[Digger1]

If you lift the plastic engine cover off,,, the black thing with 2.0 FSI on it... LOL.
Then there are two rocker cover plastic-breather hoses, I had one of those split
which caused a lumpy-tick over,as a temp; fix I put insulating tape round it as it's
a big job to remove-replace them...

 

[j3aay]

Any further ideas then lads?

I can't find the breather... I have pinched all the hoses I can find and it does nothing. I did see though that there is quite a bit of black gunk inside one of the rocker cover plastic pipes.

I guess am going to have to get it looked at unless someone can tell me where to find these breather valve things? It's the 2.0fsi (non turbo)

Oh and I took the oil filler cover off while the engine was running and the engine went really lumpy...about to stall I would say. Not sure what that means?
Thanks!

 

[j3aay]

Update...I can now smell fuel when i pull up on the driveway...seems to be coming from the back of the engine down underneath the MAF (or maybe that's the throttle body?)

Any ideas, the one Coil didnt do much. I could have more than one gone but i dont want to waste more cash until i rule other things out.

Cheers

 

[NathanA4Avant]

Bit of a thread revival, but did you get anywhere with this? Mine is running the same engine, and is doing the same thing, only i have poor MPG too. The idle seems to be getting really rough at the moment too.

Been to Audi to have the coil pack recall done, had 2 changed, and its still the same. Not due a service for a while and was just wondering if you found anything else or even fixed it?

Cheers. Nathan.

 

[j3aay]

No update from me mate. Has all new coils an still the same bag of crap. I'm just driving it, it's fine over 1k revs (may e a slight murmur but that's all). Mpg isn't great but I can live with it.

Took it to a garage and all they said was the coils...no other idea.

I'm over it, I will drive it till it dies as I have no cash to throw at it at the moment.

Let me know how you get on pal.

Good luck!