2001 Buick Regal 3800 V6 coughs on accelleration?

The engine goes "rrrrrr-cough-rrrrrr-cough-cough-rrrrr" (with the rrrr as normal) upon acceleration, from a start or full speed (it isn't related to low or high RPM). It isn't related to cold or warm engine. Engine has 145K miles. The Check Engine code says knock sensor, which is accurate. I increased the octane on fuel: no effect. I don't think there is a problem with the ignition components (spark plugs and wires replaced 5K ago...two of which are the hardest spark plugs I have ever replaced), or regular maintenance (filters, fuel system). I checked MAF: appears in good condition, voltage is normal (4.9 - 5 volts). O2 sensor was replaced 5K ago.

Mad Jack2010-11-30T13:37:37Z

Favorite Answer

You already covered a lot. The next thing I would consider would be the MAP sensor. Test it before replacing. If the MAP sensor tests good then the next thing I would consider is the throttle position sensor. Again, test before replacing. You may also want to replace the Knock sensor. Again, test before replacing.

mahfouz4life2010-11-30T18:07:05Z

I think it's fair to say that your car is probably just old. As cars get older, they don't run like they used to, they make different noises than the ones you are used to. So my diagnosis is that it's just old age :P Hope I helped!