Unfortunately, I couldn't give you an accurate diagnosis with so little information. However, from my experience, there are two most common causes for this issue. Number one is a leaking Fuel Pressure Regulator. Two is a faulty MAF/MAP sensor. Now keep in mind, there's other possible causes, such as: vacuum leak, clogged fuel filter (least likely), leaking fuel injectors, and the list goes on.
The best, but most costly, way of diagnosing your problem is to have a technician use a capable scanner to do a "live" driveability test while watching the data stream from your computer and sensors.
I know this is something you want to avoid. But consider this: If there's no check engine light or codes stored in your computer, then you'll have to test each system (ignition/fuel) and sensors one at a time. If you aren't an experienced technician, this'll take you many man-hours and you still might not find the problem.
Also, if you replace parts in an attempt to hunt the problem down, you'll have wound up spending more money this way with the possibility of not fixing the issue, than if you just paid a tech to do it right the first time.
Friday, November 19th, 2010 AT 3:19 PM