it looks like its been a while and hopefully you fixed your problem by now, but if you haven't... check your injector seals - spray some 2+2 around the injector seal at the head and look for bubbles or any change in idle. look hard - a small leak can be hard to detect and cause a lot of problems. new injector seals (o-ring, nylon seal and rubber boot to seal injector to nylon sleve) cost ~$6.00 per cylinder and easy to install. i had the exact same symptoms with my 89' 300 te and this fixed it and it was a very small leak!