Stuttering at about 40 mph and rough idle on stop lights
 

I have noticed then when driving around 30 mph and accelerating around 40 mph I feel car is stuttering or hesitation a little bit and then it goes away.


Also when at traffic light intermittently car shakes almost like rear half of the car is shaking /wiggly/jingly intermittently for few seconds.


Any ideas what's going on?

Those are the symptoms that eventually led me to replace coils and plugs. A barely noticeable stutter when stopped and a miss that seemed to disappear with speed. After about 2 months of driving I finally got the exhaust emission warning lights. Never threw a code on the ODB.

Hmmm
I was thinking of coils and spark plug as my car is 2009 DB9 with 30K miles.
But misfire from spark plug should feel shaking in front, isn't it?

V12s eat coils, so it's quite possibly ignition.

Spooky - Mines a 2009 DB9 had 29k when it happened to me. So shaking was hard to nail down. I was thinking transmission for a bit too but from threads it seems these transmissions are bullet proof so that lead me to look elsewhere.

Still have what feels like ABS catching when I leave from a stop and turn.

well I already have spark plugs Laser iridium NGK (I was thinking of replacing it anyway, so even if its not the culprit no big deal)
I will just get some coils and next weekend will be the project on the way

I'm looking real hard at a '09 DB9 with 19K miles on it. So guess I should plan on plugs and coils in about 10K miles? It still will take more than this to scare me off. At least I'll have time to plan for it.

Take a look at your mass air flows and see if they are blasted with oil before tearing those plenums off....

Actually I recently cleaned my MAF SENSORS
While I was putting my car back together after color change wrap.

How did the air filters look were they wet with oil?

Run the car in 6 gear 1500 rpm and punch it. If it is stuttering badly then you need to get those plugs changed and perhaps coils if you could verify a p code before tearing it down.

Filters looked reasonably clean no more oil than usual, only little bit.

So you mean drive in 6th gear but only around 1500 rpm then floor the gas paddle?
What mode do I drive in ? Paddle shifter with sport ?

Ok
I used article from aston1936.com
Have a Autel MD802
Checked and it said misfire learning was absent
So last night I did the procedure described 5 times going from 20-70-20-70 mph
I still feel car is hesitating, when I press gas in 4th gear or more it almost feels like inside the car there are two wheels with ratcheting teeth trying to grab each other and not able to do that properly. I wonder if it's transmission problem.

There is no error light nor error code stored in OBD2 code reader.

If it was misfire in cylinder would not I get check engine light?

Learning the misfire corrections probably won't help if you've got weak plugs or coils. But having them learned *will* help the computer detect misfires.

I had no misfires detected before the learning procedure. Now I'm getting misfires detected.

Would misfire trigger check engine light?
What are the symptoms of misfire do you get similar stuttering?

I've got rough idle. I also had the stuttering you described -- low revs, higher gear, step on it -- but a couple of cans of injector cleaner in the gas tank cured most of that (I used Sea Foam). The idle also seemed smoother while the additive was in the tank.

At some point misfires trigger the CEL and "Emission Service Required". I've got CEL on now. New coils are on their way from England.