91 2.0 Mk I or II? - manokent
Hi all,

I just bought an H reg. Audi 80 2.0E saloon, low mileage at 51k. The logbook says it was registered in May 1991 which I assume means it's a MkII. However, is there a way I can double check, i.e. via the chassis number?

Also, the engine is a little bit lumpy in idle, less so when it's warmed up but still quite shuddery which doesn't seem to effect it's acceleration. Hasn't cut out on me and isn't a major problem at the moment but want to rectify early if possible. Where do I start to track down the cause?

One more thing, probably completely stupid question... I've noticed a constant, whine/hum coming from under the car which is on even with the vehicle standing. Is this normal and something to do with the fuel system or brakes or something?

Thanking you in advance.

91 2.0 Mk I or II? - Steveieb

Definitely a Mk1. The first Mk 2 (B4 model) arrived under the J plate. You can get a haynes manual for this model but not the Mk 2. So take a look on Amazon for the picture.

91 2.0 Mk I or II? - bell boy
Audi 80 1986-1991
To compare the -86 and the 86- models look at the bonnet, the -86 model has vents whereas the 86- does not
Audi 80 1992-1994
This model has an oval hole in the bonnet for the grille.

dont shoot me ive copied and pasted the above

as for the lumpiness,check the rubber between injection system and inlet manifold ,im sure these used to open up
i only remember these audi 80"s for the fact i used to see lots burnt out under the bonnet so i often wonder if this was why
well built cars mind

as for the noise whine/hum? make sure a bum isnt sleeping under a wheel arch in these depression times
91 2.0 Mk I or II? - manokent
Thanks for the responses guys. You're right, it's all about the shape of the bonnet. There are 2 raised lines running from front to back on the bonnet for both models. the difference is:

MKI: the lines end up a few inches either side of the grill.

MKII: the lines cut in more sharply and end up exactly on the ends of the grill

Overall it gives the MKII a leaner, edgier look and the front headlights look more rectangular.

As for the whine under the car; nobody asked me for any spare change under there and somebody told me it was my fuel pump which is located near the tank which made sense.

The lumpiness I still need to look into. Bellboy; my car is fuel injection so would that put your theory out? Another thing, I bought a load of bits for a good service, changed the leads, dis cap, rotor arm and noticed the difference in terms of response but still lumpy. Stopped at the air filter because ran out of time but it looks like it goes under the fuel injection system which looked a bit more complex than I've ever seen. Does that sound right? And could a dirty air filter cause lumpy idle?

91 2.0 Mk I or II? - Cambridge
Change the spark plugs.

I had the same symptoms on my Passat - lumpy running and wanting to stall. New plugs cured it.

Good luck.
91 2.0 Mk I or II? - manokent

Dang, forgot to mention I did that, with brand new Bosch ones but no change to the lumpy idling. And tbh the old plugs weren't dire, not pitted and a relatively healthy brown but I changed them anyway. In terms of wot's left to do with the initial servicing I've got to change the oil, fuel filter and air filter. Once that's done if there's no change to the lumpy idling it'll be real problem solving time.

It's idling at about 900rpm at the moment which I assume is okay, unless it's too low and needs to be higher?