After around 200 miles after changing out the timing belt, all acc. belts, valve cover gasket, and spark plugs the car stutters at stop lights. It only happens every now and then, and only at a light or when you have it in drive and the brake applied. It seam like it is about to die then it revs back up. On the highway the car runs awesome and pulls like it did when it was new. I tore apart the entire car when I first noticed the stutter to make sure the timing belt did not skip a tooth. Everything was lined up correctly and there was the correct amount of tension on the timing belt. I also ran a can of sea foam in the tank and put some thru the vacuum lines to clean things out. Does anyone have any ideas on what would cause the stutter?

Just today I have, cleaned the TB, IAC/ISCV (with TB cleaner), and the MAS (with the special MAS cleaner). The only thing I accomplished was bringing the idle up. I adjusted the idle and the car still stutters at low RPMs. I am out of ideas. Please help.

Is there an MIL? Did yu check to the boots of the ignition coil? The 2 other wires? Is the spar plug gap within specs?

I am not sure what and "MIL" is. The wires I are fine, I inspected them when I replaced the spark plugs. The spark plugs are platinum so there is no gapping required. When inspecting the boots of the ignition coil, what am I looking for as far as defects?

Yeah Platinums sure are non gapping but i always check with a feeler gauge just to make sure , i just about always use platinum NGK or Nippondenso plugs but i always check just to make sure because sumtimes the boxes get accidentally dropped , etc and the tips sumtimes mis adjusted. On the boots just check for whiteness or arc lines anywhere on the boot base or the upper part where it seats near the coil , sometimes the high tension lead spring inside the boot that works as the conductor mis seats when re installing the coil on the cam cover. Yuve said all vacuums are on , tightlly , no hoses are cracked, the spark plug wires are in good condition , the metal leads inside teh boots and the boots were okies etc. Seems yuve covered everything else i think.

"MIL" Malfunction Indicator Lamp , check engine light , if the timing was a little off teh computer should have picked it up and set of the check engine light , But yuve checked the timing marks on the timing belt already. And im sure yuve never messed with the reluctor ring on the back of the crank sprocket that that the crank position sensor picks up off of. I cant think of anything else , yuve checked all vacuums , etc. There seems to be as frum wut yuve described a slight miss at idle . The ignition timing im sure is not the key , the belt would have to be a bit off of its mark for that , but then yu would have issues all teh time , it would not drive fine , down the road it would still miss and have loss of power.

Have yu replaced yur PCV valve? is the check valve in it working?There are no audible vacuum leaks? A small vacuum leak can cause the issue yu have or sumtin like not so much one of the 2 coil wires id think but teh boots on teh coil themselves , the high tension leads specifically that are in the boots that are the conductor between the coil and plug.

Update. I checked the spark plug wires and noticed that there was arching occurring at the bottom of the tube. I bought a new set of wires and it fixed the problem. A couple of days later the car started running rough. I checked the timing belt and I also noticed it skipped a tooth at the oil pump sprocket. The balance belt was still dead on. Now with all that fixed and everything lined back up, the car vibrates at high RPM. Is it possible to over tighten the timing belt and cause the engine to vibrate?

In a sense the belt can be sorta overtightened but that should not cause this issue. A vibration at upper rpm would be most likely one of yur balance shaft(s) are out of time. That or a loose engine support.