This question is best suited for someone very familiar with how to get the cam timing correct on a 2.4 turbo.
I have a 2004 2.4 turbo PT Cruiser that was had just about everything done to it but it has poor idle quality. At idle it has a slight or sometimes quite noticeable "rump rump rump rump" to the idle. The car also tends to hesitate somewhat on takeoff. Car drives fine otherwise, gas mileage 20+ combined, no smoke, coolant loss, no codes etc. It will occasionally throw a random engine misfire code if I let it rump rump rump too long. But it's only done it 2-3 times in 6 months of daily driving.
I bought the car needing a head gasket, went through all that, had the head rebuilt, all new gaskets(intake, exhaust, valve cover, etc.), factory correct spark plugs, factory wires, replaced coil, 140psi in all cylinders, new sensors, looked for vacuum leaks, timing belt water pump tensioner and idler all done when the head was done, injectors cleaned, even swapped...all resulted in no change in idle quality, all done after the head/timing belt job.
My question is about the precision of the cam timing procedure. Lets say I was one tooth off, either one cam or the other or at the crankshaft cog. When I did the belt, I didn't really have any trouble at all getting the cam marks to line up nor the crankshaft TDC reference mark to point to the alignment mark on the oil pump housing, and I properly set the tensioner. BUT...every reference that I see on how to do the timing belt job shows that you should place the exhaust cam 1/2 tooth off center, clockwise and the crankshaft cog pointer should actually be aligned with the trailing edge of the tooth, not the center. I had the cam marks aligned with each other (not w/the exhaust cam turned slightly clockwise) and the crankshaft cog pointer aligned with the center of the tooth, not the trailing edge....