Vehicle Info:

• 2007 Honda Fit Sport (GD Japan version with USDM)
• 82,000 miles
• Prior owner (wife's mom) experienced some stuttering which she "band-aided" with fuel injector cleaner, which seemed to have temporarily subsided the symptoms
• Just did a valve adjustment myself (first one *pat on back*, 5 hours in a baking hot Florida garage)
• Intake valves were between .009 and .010, now .006
• Exhaust valves were between .004 and .007, now .012
• Also cleaned and checked the gaps on the plugs, which were within specs.
• Car still has original plugs and coil packs (with red tips)

My wife, who is the primary driver, had been experiencing some stuttering while driving. Then while at a stop light the car fully stalled. I did some research on these forums and that lead me to do the valve adjustment.

So it ran like a champ for a day. Now it is stuttering really bad, however it is only when the air conditioner is on and it is in gear. When it is in idle, even if the A/C is on, there is no stutter.

Here is a video of what I am seeing and hearing the engine do in the various stages.

Not sure if this is an alternator issue. But the battery seems to be fine, holding at least 13.1v even after multiple starts.

I don't hear any vacuum leaks or cylinder drops/plugs not firing. I'm at a stand still and need to fix this quick since it is our only vehicle.

 

So, I haven't had any responses, but I intrepidly soldiered on. I had Advance Auto check the battery and the Alternator, both of which checked out in great shape. Both of which are still the originals, so the battery's condition surprised me.

What I was finding was the engine RPM's would drop below 800 and it was having difficulty generating power for acceleration. So the next step I thought was to change out the spark plugs. I wanted to determine if it was just the plugs, or if it was a bad coil pack.

Many of the other posts about engine stutters, idle drops, and acceleration lags have responses that indicate that a bad coil pack is to blame. Unfortunately, like most people out there, I'm poor. So the cheapest fix for me is the best. The next step was to change out the spark plugs.

Here is a photo showing, what I think is the original NGK Japan plug on the left and the brand new E3 replacement plug on the right.

I know the NGK and Bosch have a needle-like design of it's center electrode, but the E3 plugs have a thicker, more robust looking pin.

I know the original plugs were gapped at 1.3mm (.051 in) but these E3 plugs don't say what they are pre-gapped at. All I know is the box says 3.43 (not 3.62 like the box photoed below) and the spark plug reach is 3/4 inch. This is just a photo I found of the box online.


So a quick change of the plugs and I dumped a pint of Seafoam fuel treatment in the tank. Now the engine is running fine. Power on acceleration is excellent, even with the A/C on.

Maybe this will solve your issues as well if you are experiencing the same symptoms.

• Do a valve adjustment
• Check the plugs
• Make sure the injectors are clean
• Last resort - start replacing coil packs if you don't have any codes or Check Engine Light indications

 

Having read over 100 posts on this same issue, my observations are:


1. don't use the E3 spark plug. Stick with the Denso or NGK Iridium.
2. the valve adjustment, spark plug change and coil pack replacement are inevitable with this car.


I believe you may find that your smooth running engine is very temporary. The coil packs (Hitachi) are going to have to be replaced. When the studdering returns and you have to replace them, think about putting a Denso or NGK plug back in.

 

<-- has 130k and no valve adjustment, original coil packs.

So its safe to say nothing is for sure and results may vary.

 

My 2007 Fit Sport automatic would sometimes die on me when I would be setting a stop light this past summer. It would start right back up. I noticed an intermittent misfire driving down the highway. Took it the the stealership and it showed no codes. Drove it a while longer trying fuel additives. No change. Then I noticed that it was when the air conditioner kicked on that it would sometimes die. The weather cooled off and it happened to me on the way to work one morning when the defroster kicked on. I read on this forum that a bad coil pack might cause the misfire problem so I replaced all 4 coil packs with Import Direct brand from O'Riellys and installed all new NGK plugs. Doing this seems to have solved the problem. I've put nearly 2000 miles on it mostly in town driving and haven't had it miss fire once that I've noticed. The car had 81,000 miles on it when I did this. Changing these was easy but pricey. Cost me right around $350. dollars. Couldn't say for sure which one was the culprit as all 4 plugs looked fairly clean with 2 being only slightly darker.

 

Coil Packs. Go online to get them. Got 4 for like 80$ or something. Change them all because mine started going almost the exact same time. This is extremely common on these. Mine has about the same exact miles as yours and same model. if you took out the spark plugs you took out the coil packs. It's a super easy change out/ fix.

Then engine is misfiring because of the coil packs.

 

Rock Auto Hitachi 200 for 4..

 

All 4 Coil Packs for $52.75
http://www.ebay.com/itm/-/130893082172?roken=cUgayN&soutkn=UzcFOR
This is where I got mine. They are working fantastic.

 

For COP systems I don't stray from the original manufacturer(Hitachi). Too much hassle, those things are really integrated to the ECU tune. Learned the hard way on Toyota and BMW.. I HATE and I mean really really HATE having run ability issues out in the middle of nowhere..

Oh and just say NO to the fancy spark plugs, the Iridiums are way more reliable ,, in my experience the special plugs need gapping all the time to give any benefit. NO plug is going to give you more power, its just going to help you keep what you have for its life.

Iridiums are hard to beat for street plugs.

 

Hi gsarmedic. Don't use different spark plugs like the E3 you used. The Iridium are the best, and have a very long life.

 

There are 8 spark plugs in a Fit i-DSI engine? At least there are here in Japan.

 

Hi, wage slave. I have a 2013 Fit, Flex IVTEC engine and it has 4 coil packs and uses 4 Iridium plugs. The brazilian 2003-8 Fit's used 8 spark plugs and 8 coils.