Sputter at StartUp/1999 300M

The faithful 1999, 300M with 65,575 miles, 'sputtered' at startup twice
today. Has had regular oil changes,& service, last tune-up was 38000 miles
ago. Seems to run ok after sputtering a bit. Your suggestions/advice will
be much appreciated. thanks in advance.

 

When were the ignition wires last changed? Have you pulled any of the
spark plugs to see if they are carbon fouled?

Bob

 

No plug wires on the 300M, Bob - coil-over-plug ignition.

But your suggestion on the plugs is good. Though Chrysler says the
plugs are good for 100k miles, it's best to change them before 75k -
don't inspect them and change only if they look bad - replace them
regardless.

Also, for the OP - Here's a good possibility (the most likely, IMO):
You may have a dirty fuel injector that is leaking down a little after
it sits (overnight for example). This partially empties out the fuel
rail, so the fuel pump has to refill and pressurize it before it will
run smoothly - plus that cylinder (the one with the leaky injector) will
be wet with raw gas at startup - both results explain the rough running
at startup. An extreme case of this will actually cause difficult
starting - sounds like you're not to that point. If this is your
problem, you are at the early stages.

The GOOD news is that it is easily and cheaply remedied:
Buy either some Techron™ or Sea Foam™ at the auto parts store and put
that into the fuel for the next two tankfuls of fuel. That almost
always fixes this problem. I've seen this problem reported many times
on the 300M Club forums, and this is almost always the case.

Other things to consider if new plugs and fuel injector cleaner in the
fuel don't fix it (but I think it will):
Consider cleaning the throttle body (spray cleaner from the auto parts
store - follow the directions on the can), and/or there may be some EGR
valve issues. But try new plugs and fuel injector cleaner first.

Report back on how it goes.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

thanks to all - especially Bill. Followed your advice, ran Techron thru
her and now there is no problem.. this is a fine group, keep up the good
work.
Ralph Griffith West Chester, Ohio

--
Rome remained free for four hundred years and Sparta eight hundred, although
their citizens were armed all that time; but many other states that have
been disarmed have lost their liberties in less than forty years.

MACHIAVELLI, NICOLLO, The Art of War

 

You're very welcome, Ralph. Glad it's running well again.

66k - that's low miles for a '99. Take a look at the 300M Club forums
(http://300mclub.org/forums/index.php?sid=426876de8fc01e7e267dc347d2afee34)
and see if you like what you see. Lot's of helpful people over there.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')