Guys with reference to the Original jerking problem during idle in D or N problem, if you have tried all the options as previously described in the forum, I suggest to try changing 2 new O2 sensors, as this controls the AF ratio at idle. It feels like a lean misfire stumble rather than rich misfire stumble.
As with reference to detonation, yes the VQ30 does detonate and is intake air temp related. It will detonate from -0.2bar all the way to 0bar with high load on the engine like A/C on and a slope in 2nd, 3rd, 4th gear. It will even detonate starting at -0.3 bar if your EGR system is blocked or faulty. I have tried it and if you disable the EGR system it will detonate at -0.3bar so make sure your whole EGR system is clean and working well.
Hi to all,
I have similar problem on my a32 30. Asked a few friends. One of them open hood, star engine, engage D. He notice slight movement of engine, he said maybe engine mounting koyak. Maybe true as he had same problem on 2 old cars before.
You will only have this problem when you engage from N to D or switching between gears. The problem if I understand it right is that in D when idling it will misfire and stumble. Which a broken engine mounting will not solve. If the mounting is broek when moving between the gears you will feel a "klok" feeling. The feeling that other are getting is a stumbling and misfire like when your heart skips a beat. It will idle smooth then miss, then idle smoooth then miss 2 -3 times them smooth again, all while in D but will never stall. The VQ engine should be smooth all the time.