2001Buick Regal LS sputters on start up and acceleration, but seemingly correct itself when shifted to neutral. Why?

SOURCE: Lack of power

You may either have a partially clogged Catalytic converter or you may have a MAF Sensor (mass airflow sensor) going bad. When it seems to loose power, does it want to backfire through the intake? If it does, most likely the MAF Sensor is going bad. If the car seems to drive just fine at first then starts loosing power gradually while you're driving, the Catalytic converter is most likely partially clogged.

SOURCE: Hesitates and cuts out when I accelerates, shakes and sputters!

Fuel filters are cheap and simple to change, so try that first. If that is not your problem it may be your catalytic converter. Before having that replaced, check your fuel return line. You should be able to blow thru the line with your mouth. If you can't, or it's really hard to do. . . then you have blockage. The blockage could be flooding your engine with fuel. Checking the fuel pressure with a gauge from an auto parts store may help you out. If the pressure is really high, then that may be your problem.

Harvey N Tawatao

• 3854 Answers
• Posted on Jun 01, 2009

SOURCE: Chevy S10 Pick 1995 - Sputters and almost stalls when accelerating.

You could have a dirty EGR valve, you can re move it from the manifold and clean it with Throttle body cleaner. Might as well buy two cans, since your cleaning the EGR, might as well clean out the throttle body too.
Spray the throttle body cleaner in to the throttle body with the engine running and try to keep it at 1000 rpm and then to 1500 rpm as you clean out the throttle body and let it idle down for 2 min then turn the engine off. Then turn the engine to the run position for 10 seconds and start and let idle, ro for a test drive and hope that solved the problem, if not there a few more things we can do which will consist for tune up.
Note: Clean the EGR first so you don't burn your self since the engine would still be cool before you clean the Throttle body.
Good luck and keep me posted.

SOURCE: 2004 Buick Regal. Hard tranny shifts.

Try some Lucas Transmission fix. that stuff has done wonders for almost all of my tranny problems

SOURCE: sputtering on accelerations

If no check engine light is on, I would try to replace the coil pack first. Usually on these cars a drop in fuel pressure associated with a bad fuel pump should throw a code.