Cold hesitancy

[WillRS]

quick question people..

I noticed from quite early on in my ownership that sometimes my car is a little hesitant for a few minutes (maybe as much as 5 or so) after starting. feels like its misfiring I guess or almost like i'm tapping and releasing the accelerator and getting the surge / stop effect that that would cause (but i'm not). this seems to happen at lower revs and speeds (i.e pulling out of drive etc when I drive off in the morning). It wasn't however doing this all the time. maybe one in 5 or 6 starts

I hoped this would go away when I got my plugs changed (they needed changing anyway) but it made no difference at all.

For some weird reason the problem seems to have got worse i.e more regular since i've had my oil cooler and pipes replaced but i'm guessing this is a coincidence as I can't see the two areas can be linked ?!

I have read about the software update which is now quite old i guess which addresses cold start issues ? - I'm assuming my local dealer can check if this has been appplied or not ? if it hasn't I assume this is a free ecu update yes ? if its not that, whats the deal with the coilpack replacement i've read about ? is this something thats done foc (if its the problem)

has anyone else had this problem and if it wasn't any of the above, what was your solution ?

p.s there is no check engine light etc coming up and the problem is ONLY when it first starts having been left standing for a while (overnight or throughout the day)

thanks in advance

[klauster]

All RS4s do this, it is improved with SW0090 being performed which is the newest program I believe....

I know that mine use to do this and it's been mentioned on here many times

[klauster]

With regards to getting the update, some dealers are better than others, mine was proactive and listened to me, but I have read about others being charged for the update, or some dealers saying they don't know anything about it at all

[johnnydog]

There is loads of info about this on here. It also may be worth asking if any member knows if there is an code / reference within Audi for this update, which, as said, is now quite old. An Audi Technician friend of mine has stated that there is now no reference when I recently asked him, to either SW0090 or cold start issues on the system (is it TPI's?) for the RS4 - whether he wasn't checking it correctly, but maybe someone could point WillRS (and me!) in the right direction with the TPI reference so that it can be found? Disappointing though that it may be a case of doing their own job for them...

[PeteS4]

Mine had the cold start hesitancy. Stupidly I cleared the fault code log in the car with my VCDS cable, although I kept the log file on my laptop. Even though they tested it and found the problem (only on one occasion), they needed a fault code in order to get the 090 update from Audi

They installed the update in the end and there are no more cold start issues. The stealer told me that they get charged for the update from Audi when there is no fault code.

[WillRS]

i've asked Camberley Audi (my local dealer) who are one of the best RS specialists (non indie) round this part of the world.

will let you know what they say.

I can't believe everyone with an RS4 has or puts up with the sort of hesitancy i'm getting at the moment so loads of people must have had the update done (assuming that resolves it)?

[adsgreen]

I haven't had the update (I don't fancy 30 seconds of 1800 rpm on cold start with a miltek).

Mine did this alot pre-plugs change. After that it's not missed a beat.

Also worth double checking the oil level to see if it is too high - given that oil can be sucked up into the intake system (and smoke out the exhaust) it probably won't help things on a cold start.

FWIW I don't think you have to get the upgrade. Before my plugs were replaced as part of normal serving I used to manuall keep a slightly faster idle (1300 rpm or so) and on the first couple of pull aways don't use much throttle and leave the car in 1st up to about 4k rpm. Seems to clear it quickly.

[WillRS]

interesting - I wonder if the extra oil they added for the oil cooler change perhaps was slightly too much as its definitely worse now than pre oil cooler change.

assuming it had been slightly overfilled, will this clear itself or is it not as straight forward as that ?

[adsgreen]

It will eventually clear as its used but I would ask them to extract it as it will cause problems

[sync24]

I noticed that sometimes my car is a little hesitant for a few minutes (maybe as much as 5 or so) after starting. feels like its misfiring I guess

Mine does this as well - every morning just for a couple of mins - I just assumed that they all did it. Would be good to get it resolved - I'll ask the tech on Sat when mine goes in for a MOT and free health check ETC.

If anyone else can confirm the definitive TPI that would be great and I can arm myself with the info before I go.

[WillRS]

It will eventually clear as its used but I would ask them to extract it as it will cause problems

I would point out that I think its unlikely it is overfilled as my local dealer is very good but I will just check this evening anyway just in case...

[sonny]

Dirty air filter can cause problems, change it/clean it.

Have you changed fuel brands?

As above regarding the oil too, worth checking.

SW0090 is great but the cold start is a pain. I believe not all RS4s suffered.

The faulty MAF may be part to blame, I changed mine out last year as it was faulty, prob due to the years I have had the high flow filter on.

[Timster]

I haven't had the update (I don't fancy 30 seconds of 1800 rpm on cold start with a miltek).

It's 60 seconds, not 30.

[EddyPee]

Interestingly I topped mine up with oil yesterday, it was fine this morning but it was really lurchy, the worst I've ever had when I came back to it this afternoon after being sat for most of the day.

Mine tends to be bad when a coil is about to go and I've had 4 go in 15 months. I also believe I'm on original spark plugs and fuel filter which maybe might not help?

Be intersted to see what camberley have to say as mine will be going there soon.

[PetrolDave]

I haven't had the update (I don't fancy 30 seconds of 1800 rpm on cold start with a miltek).

It's 60 seconds, not 30.

It's not a fixed length of time - it's dependent on how cold it is, as it happens until the temperature sensor reaches a threshold value.