Slight hesitation while accelerating in second gear

[RGC]

As the title says

hoping its not the gearbox

1999 A8 2.8 APR EBX

while acceleration softly in second and the revs come to about 2300 the engine hesitates for a second and the revs drop around 100rpm then start back climing again steady ?!

any ideas much appreciated

Richy

[Norretal]

Howdy Ricky, welcome to the forum. You're only a few miles from me

I had a very similar problem around 5 months ago and thought it was the gearbox starting to disintegrate. It turned out to be several faults on the engine management side and not mechanical at all so I'd suggest you get it plugged in and get the fault codes identified. I would be accelerating from standstill and feel what I described as a shunt or hesitation and I definitely thought it was the gearbox, thankfully I was wrong.

Good luck, let us know how you get on

[B@fink]

Hurrah, another 2.8! Have you checked the plastic corrugated breather pipes that run around the top of the engine? They get brittle with age, crack and let air in which would give a weak mixture which might cause a stutter? Air mass meter might be getting a bit past it which might cause similar? If it hasn't been serviced recently then make sure the air filter and plugs are swapped, best to make sure the basics are right before searching for other problems!

[Norretal]

Sorry Richy, got my glegs on now so can see your name properly

There's loads of info on here and an abundance of members that know everything about A8's so I've no doubt you'll soon find a solution, and hopefully at very little cost

[RGC]

Hi matey thanks!

small world eh!

yeah i had a feeling it may be engine related but on scanning found no codes so don't know where to start this is my first a8 so need some pointers haha I'm used to Diesels! I can pull them apart and rebuild them in my sleep ha

Richy

[RGC]

np Norretal anythings better than Dick haha



B@fink ill have a look at them in the morning are you on about the crankcase breather hoses?

plugs oil and filter done not long back,

ill get a hold of some switch cleaner and give the maf a blast too see if that helps

[B@fink]

I think it's the crank case breather, it's the formed corrugated black trunking about 3/4" running from LHS of engine, behind the coil down the RHS and then into the depths behind the RHS rear. When I got mine it was one of the first bits I swapped, they were completely disintegrating at even the lightest touch. The access to the rear of the engine is a pain but the rest is easy to get at once the vanity plastics are un clipped.

[RGC]

B@fink - thanks will have a butchers

[Dezzy]

Hi and welcome.

Do you have or have access to a lead and plug the car in? It would be my first point of call, plug in run a scan, jot down any faults, clear then and run the car for a few days and the plug it back in and re-scan and see what faults come back.

[ainarssems]

Does it work OK at full throttle at the same rpm?