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View Full Version : Low speed/rpm miss or hesitation


sking
08-13-2010, 08:08 AM
I have an 2003 Marauder with approximately 170 k on it, I know that is a lot of mileage but it runs and looks brand new. Recently I have been experiencing a low speed/rpm miss and some hesitation when accelerating slowly ( I know not many of you have ever accelerated slowly). If I tromp of it I don’t notice it.

My mechanic has not been able to diagnosis it and does not get an error code. He was able to replicate the issue but by the time he got the scanner on it stopped doing it. He pulled the plugs and they look good, he suspects the ignition coil but as I understand it the Marauder uses a Coil-On-Plug (COP) system at about $100.00 a pop and without an error code he does not know which one to replace. I have a long relationship with guy and he is not one to throw parts at a problem. Any ideas.
babbage
08-13-2010, 08:12 AM
just change all of the cops anyway - it's time.

next!
Blackened300a
08-13-2010, 08:13 AM
You would have to have the coils tested or get one coil and keep trying it out til the miss goes away. It seems that the light never comes on when one starts to fail. I drove on 7cyls and the light never came on.

Contact Musclemerc. He has a connection for coils and it cost me $110 for all 8 coils.
fastblackmerc
08-13-2010, 08:16 AM
My bet is on the coils also.

You can also clean the MAF. Use only MAF cleaner.
Got_1
08-13-2010, 01:59 PM
tell him to perform a power balance test. that will bring out the weak coil
fastblackmerc
08-13-2010, 02:28 PM
tell him to perform a power balance test. that will bring out the weak coil

With 170k miles... I'd just replace all 8.
J-MAN
08-13-2010, 05:23 PM
You would have to have the coils tested or get one coil and keep trying it out til the miss goes away. It seems that the light never comes on when one starts to fail. I drove on 7cyls and the light never came on.

Contact Musclemerc. He has a connection for coils and it cost me $110 for all 8 coils.

Musclemerc hooked me up with a set, what a deal! Truly a gentleman and scholar.
frdwrnch
08-13-2010, 05:29 PM
Got to admit with that mileage you will be chasing coil failures.I would also recommend replacing them all. If you only want to fix the one, you will need to duplicate it during a power balance test to isolate the problem coil.If you have not done plugs recently then do them as well. Plug resistance affects coil performance.