Just noticed in the last two days that my 2008 Sport/AT with 78,000 miles is stuttering when i come to a stop. This AM, when i pulled into the parking lot at work, i noticed it was doing it, but when i turned the headlights off, the stuttering went away. As background, 2 weeks ago, the temps were pretty low, and the car wouldn't start until i charged up the battery (the car sat for about 10 days without being driven in temps that were between 0 and 15 degrees). Since then, it has been driven every day, and it starts up fine (temps in the 20s and 30s now). The 51R battery just turned 4 years old. So i'm wondering if i need an alternator, a battery, or if the stumbling is due to coils. I dont notice anything when driving down the road, just when i come to a stop, and have my foot on the brake. I didnt notice it yesterday afternoon on the way home, but i did not have headlights on at that time either.

 

So let's start with the obvious: does your 51R battery have the two square pry off ports on top and if so, when is the last time you added distilled water to each individual cell? If you have maintained your battery, I'm guessing your battery is fine at 4 years old. Second: have you had your valves adjusted in the car? Lastly: have you had new plugs and ignition coils? All these things have to be done at some point. They cannot be avoided and at some point, you'll have to pay the piper. As for the alternator, they certainly do go bad. I had to have mine replaced in my Vibe when it suddenly died at a gas station. I could turn on the lights, but the car would not even attempt to start. Jump starting worked, but soon died again at the next stop. While I know this note doesn't solve your problem, you are on the right track; but first, check the battery cells and add DISTILLED water and ensure the terminals are clean.

 

What is the idling speed with headlights ON transmission in park or neutral?
You can probably rule the valve clearances out if engine is not dying cold.

 

just a little update....on the way home from work, I was doing about 65, ran into to some slower traffic and coasted, as traffic let up I accelerated a bit and got some hesitation. That was the first time i'd noticed it other than when I'm stopped. Seems to take about 10 minutes of driving before I notice it. when I got home, I left it in "D" with parking brake applied and would get stumbling, once the engine almost died. I tested the battery with a little 4 ball hydrometer and all cells had all 4 balls rise, for whatever that is worth. After I tested the battery I started it back up and put it in "D" but for 5 minutes it didn't do anything. I'll fiddle with it some more today since i'll have more tie to play.

 

I pulled the coils and cleaned them up according to this link:
https://www.fitfreak.net/forums/fit-...e-answers.html

I also went ahead and put new plugs in. Went for a test drive, and about 5 minutes into it I felt a little shudder, the engine light blinked for about 10 seconds (then went away) and when I got to a stop, the engine was stumbling. LIGHTS WERE OFF. Lights seem to not change the effect now. the number 3 coil looked different from the other 3, it looked like it had rust covering it--even the upper ceramic portion of the plug had some orange on it. The coil's red boot was discolored, and it was like it was glued on-the other 3 slipped right off. Think i'll start buying coils, maybe just replace the #3 first and see what happens.

 

see if you can beat this price for an OEM ignition coil.

https://www.conicellihondaparts.com/...dXRvbWF0aWM%3D

Conicelli in PA is also giving 5% off right now (go to their facebook site:
They are in the process of redoing their website so I believe in just a few short days, that 5% off will turn into something even better. But if you cannot wait:

https://www.facebook.com/Partznet

They sell OEM parts for Hyundai, Honda and Toyota and Nissan. I plan on buying 4 new ignition coils for my "Toyota" Vibe when their big announcement comes out and their website is redesigned. I'm guessing it will get bumped up to 10% or more. To get to the links for all 3 auto makers, click on the first link I have above, then click on the Conicelli Autoplex link at the top of that next page; then click on PartZnet link at the top of the following page. You then will see the 4 auto maker's logos. Select yours and find some excellent prices.

 

quite a bit cheaper at rockauto for hitachi coils . I just paid about 45 bucks each for four.

 

right you are. I had forgotten; that's where I got my Hitachis too. Good catch.

 

okey0 I don't know much about these things, but if I were you I'd look into the plug in that cylinder and find out why that orange crap is fouling things up. I bet there's people on here who know immediately what's going on there. Plug loose? exhaust valve clearance? Don't throw money at new coils until you diagnose and fix that problem.

 

okey0 I just read over your post and realize that you put in new plugs before that coil got covered with exhaust...You really gotta go and tighten those plugs again.

 

Coil #3 has a leaking plug. The brown "rust" deposits are the combustion gasses slipped past the plug gasket

 

ordering new coils. been planning a valve adjust for may (vacation) but may need to move that up. plug 3 took the same amount of effort removing it as the other 3, so hoping that is old damage. the new ones are all in with 14 ft/lb of torque. I guess what threw me originally was the change from headlights on to off resulting in stutter going away.

 

Please post an update, how it goes.

 

UPDATE: it was the number 1 coil. as soon as i replaced it, all was calm. now have 4 fresh coils, should be good for another 78,000 miles. will definitely keep an eye on cylinder #3, since it had those signs of leakage past the plug. sorry to start another coil thread. THANKS to all.