# Engine stutters sometimes:

**URL:** <https://community.cartalk.com/t/engine-stutters-sometimes/31962>\
**Category:** Maintenance/Repairs\
**Tags:** sparkplugs, engines\
**Created:** [June 16, 2009, 7:58pm UTC](https://community.cartalk.com/t/engine-stutters-sometimes/31962 "2009-06-16T19:58:22Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Cal-Georgia](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@Cal-Georgia](https://community.cartalk.com/u/Cal-Georgia)\
**Post date:** [June 16, 2009, 7:58pm UTC](https://community.cartalk.com/t/engine-stutters-sometimes/31962/1 "2009-06-16T19:58:22Z")

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Have a 2002 Mercury Grand Marquis LS, with  
  
 103000 miles on it. Replaced radiator hoses  
  
 flushed engine, and replaced antifreeze. At  
  
 the same time replaced spark plugs with AP104  
  
 plugs from as Napa auto supply. Upon conclusion when running at 60 mph, engine  
  
 stuttered, then check engine light showed  
  
 up. Test showed cyclinder 1 misfiring, reseated plug wire, runs better, for awhile. Now it begins again with the  
  
 engine stuttering, but light does not  
  
 come on, and it is not as bad as it was  
  
 at start. Any suggestions as to problem?

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**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\
**Post date:** [June 16, 2009, 8:16pm UTC](https://community.cartalk.com/t/engine-stutters-sometimes/31962/2 "2009-06-16T20:16:52Z")

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I assume you had no problem before the above work.  
Did you check the gap on all plugs? If so…

Could be a bad plug.  
Could be a bad coil.  
Did you damage the wiring to the #1 coil?  
Is there coolant in the plug well?  
Is the plug correctly screwed in?

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<div class="post-metadata">

**Author:** ![Cal-Georgia](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@Cal-Georgia](https://community.cartalk.com/u/Cal-Georgia)\
**Post date:** [June 16, 2009, 8:31pm UTC](https://community.cartalk.com/t/engine-stutters-sometimes/31962/3 "2009-06-16T20:31:31Z")

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A mechanic friend did the work saving me 400.00 from estimate given by a Goodyear  
place. Have not called him after he fixed it first time, wanted more detailed  
information to ask questions better. He said access to plug wire on cyclinder 1  
was very difficult and felt he may not have seated it properly, which fixed it  
for about 2 weeks, but it appears to be restarting to stutter again but not as  
harsh as first time. I believe plug has been installed correctly, and gapped. Was  
wondering if there plugs were the correct type. My friend hinted we may need to  
replace them with Motorcraft, if the Autolite ones continue to act up. Does this  
sound possible?

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**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\
**Post date:** [June 16, 2009, 9:46pm UTC](https://community.cartalk.com/t/engine-stutters-sometimes/31962/4 "2009-06-16T21:46:17Z")

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Autolite should be okay. I am confused by your mention twice of “plug wire.” This car does not have any plug wires, it is Coil-On-Plug. I don’t recall ever having any trouble getting to any of the plugs on this car.

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<div class="post-metadata">

**Author:** ![Cal-Georgia](https://avatars.discourse-cdn.com/v4/letter/c/c6cbf5/32.png) [@Cal-Georgia](https://community.cartalk.com/u/Cal-Georgia)\
**Post date:** [June 16, 2009, 10:20pm UTC](https://community.cartalk.com/t/engine-stutters-sometimes/31962/5 "2009-06-16T22:20:31Z")

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I’m not sure, he may have used that terminology to make it easier for me to understand.  
Last time I worked on a car, ignition, engine and etc, was back in 1970, and then it  
was on older vehicles then that, like 1950-1968. I would need to talk with him before  
I can say much more, so will check with him and then respond again in a day or so.  
Thanks for your help to this point. Will let you know what happens.