Rambo420

My 97 A8 starts fine, sounds great during start up, then starts to miss in cylinder 4 and 5 during idle throwing codes, p0304, p305, it also threw code p0321. When I drive it shakes violently right at 1200 rpm. “smooths out”, still with misfire, when rpm is increased. I’ve been looking all over forms and can’t connect code p0321 to the misfire.

jfrahm

What do the plugs look like? After running badly, any indications of carbon, wet with fuel, wet with coolant?
If they seem wet with fuel, you could try moving those coils and seeing if the problem follows the coil(s)

I would also suggest a quick compression test.

Rambo420

The spark plugs look fine, I changed the coils around (changed 3,4 and 5,6) and now it is throwing codes for 3, 4, 5, and 7 (7 looks like the only “old” coil and yes I cleaned the codes). Still throwing the p0321 code Gonna replace the crankshaft position sensor and see what happens.

ceaser

Hi Rambo, have same vehicle, and when I googled your Code p0321, it gives the same symptoms as the G28, which you have decided to replace, this I believe is the correct choice, don't know from where you are from, guessing the US, and maybe they still have the original part available ie the :Square 3 flat Blade interface: otherwise I found it impossible to find from aftermarket or from the dealers, Bearing in mind this is Cape town but I can usually get original parts from the Factory, but not in the case of the G28 , so I baught the after market replacement ; Oval interface which doesn't fit the D2, and to try trace and replace the unit back to the ECU is nigh impossible . Asked the Sparky if a cut and join/splice into new sensor side would be OK ,said it would be OK. So I did , worked fine for 12 months to the day, then a/market G28 packed in,!!!, then found out that the A/m part wasn't a reliable product , now comes the Good News, I went to a Auto Spares Retailer (Midas) for some other part and was browsing the display of Senders , and found an OPEL Sender which was physically identical to the Audi D2 part, the difference being the Ohms Resistance, the Audi should be about +-900 the Opel part gives +- 600, and Cost South African Rand +- R350, the A/M part cost +-R900 the Audi part which didn't fit interface R2200.00, which Im also told is no more reliable than A/M parts, so what did I do, fitted the Opel part and 12 months later, my Audi 1995 D2 Runs like a Dream, and I'm so expert at changing this part that I can do it in 3 hours , if need be.