On Wed, 25 Feb 2009 20:06:07 -0600, "Robert Swinney"
wrote:

Our 2004 Pontiac Bonneville GXP has developed a low speed miss. It is particularly noticeable when
the engine is cold. It seems to miss only at idling speed and is worse before the engine warms up.
The miss goes away when you load the engine under acceleration. At only 36000 miles it shouldn't
need a major tune-up. I am guessing a dirty fuel injector. Any ideas appreciated.

Bob Swinney

Silly question number one: Is it throwing a computer code and
lighting the Check Engine Light? And if so, what are the codes?

If it's enough to worry about, the OBD-II computer will notice it.

Only at idle, worse when cold... You might be right about a dirty
injector. Try some Chevron Techron additive in the tank first.

If that doesn't work, buy or borrow a fuel-rail connected injector
cleaning kit and a can of the cleaning solvent. The kit costs about
what you'd pay to have it done once, and if you are careful to buy a
decent one it will be good for many years.

-- Bruce --