2.4 liter eng, (fuel preasure regulator) ??? high miles 97000 just started acting, runs good, but sometimes at traffic lights, pic-up is hesitant, then goes,sometimes wants to stall, Son brought it to auto class put it on scope O.C. sensors didnt pop up, tried can of throtle body cleaner, with fuel injector in gas, seems to run better, 1 week later acting up a bit when stopped. any help would be appreciated