just before to purchase 400$ worh of coils, i'd like to ask you one last thing

I have no CEL
Car isn't shutting off

my problem is when I accelerate more than half the gaz pedal, below 2K rpm, the car stutters, like if I was hitting the cutoff / having a misfire

do you guys think I have the coils problem?

 

The problem you are describing can be coils, plugs, or ECU problems but not guaranteed to be that, just mostlikely.
I don't know what a CEL is but an OBDII scanner would the first step at one of the car parts places like AutoZone, Advance Auto Parts, or Oreillys. They could tell you which coil.
If you habve more than 40,000 miles, 60,000 km, the most likely cause is the coil packs and while you're at it change plugs too. You might try changing plugs alone first to see if that could be the cause, and if not, then replace the coil packs.

 

I had the same problem in my wife's Civic at 20000 miles. I don't know if it was a coil problem but I think it has more to do with carbon build up. I would do a ECU reset by disconnecting the battery and fill up with better gas and fuel injection cleaner and take it out on the Highway doing some full throttle runs from 45 to 60 mph. I would also check the plugs and depending on the miles would adjust the valves too.

 

Check Engine Light

A DTC (Diagnostic Trouble Code) in Honda-speak.

 

Do you have a good injection cleaner to recommand?

also, i've removed my plug today

spark plug are Denso, they look new, a little white. they are all gap to .55

Coils have no visual defect.

concerning the valve, I might also check this, maybe do it myself

I also might give a try buying all four coils on ebay for 150$

thank you!

 

Look, do the easy and cheap stuff then the more costly and time consuming .
1. check the OBDII for codes and problems.
2. If none, clean or replace plugs. You can't 'look' at plugs or coils and tell if they're bad unless they are damaged.
3. Then think about 'blowing out' the carbon and then set valve clearances.
If that doesn't get it go back to square one.

PS be careful of 'cheap coil packs on the internet. Many are coming from offshore and of very poor quality.

 

Figured i would explain my story, may help someone. and or, someone can help me. i have 2008 fit. Stuttering started around 170k, after getting gas. got progressively worse for a few months until i came to this site and got some info. tried cleaning the coil packs and made the car worse. tried cleaning again and totally killed one and started running on 3 cylinders( i can only assume this info, i dont have computer checker thing). bought a coil pack, replaced first one to see if problem would go away, and bam, it did. still seemed down slightly on power and fuel economy, but ran very smoothly and i was happy. got gas the other day (at same station ) and noticed a hint of stuttering like before. 2 days later its bad again. WTF. Very possibly just another coil pack finally letting go, but intuition says otherwise. I know coil pack fixed issue for a few weeks last time, and i know i dont have a ton of money to throw at this. Any one with any knowledge/experience have a smart next step for me?

 

My problem with 2007 Fit was identical. I replaced spark plugs, adjusted valves at dealer, replaced coils, all to no avail. Dealer couldn't even fix stuttering and various codes. They said it was the cyl head (which it turned out was not a problem). I got fed up and bought a salvage engine, swapped out the old engine, and it runs perfect now. So one thing's for sure is that it isn't the ECU. I noticed a decent amount of carbon on top of pistons. This could be a problem. I also noticed that when I did a leak down test on the new replacement engine, tapping the valve stems with a plastic mallet dislodged some carbon or junk between valves and valve seats and I got much better leak down test results.

I'm still not decided if I should sell my good running Fit now, to avoid another future, unknown stuttering issue.

 

Does it do it regularly at idle?

 

the first time i had the issue, which was very minor at first and slowly got worse, no. the idle always seemed fine. after i tried cleaning the coil packs my problem was worse and the idle would skip when the fan turned on (which is constant in my fit!). then when the second coil pack went, it very quickly deteriorated and the idle was bad at all times. so from my experience you dont always get a rough idle when the coil packs are going, but it will eventually happen.

And for an update, i put another new coil pack in and the cars great again. although still feels slightly down on power and fuel economy. but beggers cant be choosers. thanks for all the help fit forum people, you saved me a lot of money.

 

I like Redline Total fuel injection cleaner. Red Line Synthetic Oil - Gasoline Fuel Additives - SI-1 Complete Fuel System Cleaner

1 bottle lasted me 3 months.

 

The design life of a coil pack is 50,000 miles, not 100,000. Neither spark plugs nor coil paxcks are maintence free and the plus/minus 3 sigma spread on those is about 12,500 miles, m reasning a failure is 95% sure to occur between 38,000 and 62,000 miles.
Its not a defect but a response to the tight emission regulations.
And btw Honda didn't develop coil packs, suppliers did.

 

Lets see: ChE, ME, and QsE. And 50 years experience including 3 servic e shops I oiwned.
And yes, I do prefer carbs, especially Webers, over FI even tho I'm fully conversant with FI; its all coil packs I dislike simply because they are so costly to replace when they have to be. The computer distributor is still wondering where manufacturers saved money or emissions control with coil packs. A cost of $400 for coil packs and $50 for plugs plus labor is ridiculous for a 50k or sooner tune up
Perhaps you will enlighten me on the differences between coil packs from different makers.
BTW, I've also owned more than 150 vehicles and raced several so like Car Guys I've seen a bunch of car stuff many tim es.

 

Yes but they developed the ecu. There is no reason the coils cant last and if you use the right oil and fuel it will last at least to 100,000 miles. My dad has used Kendall oil and premium fuel in his car since day one and has no coil failures. The car is 16 years old and has over 100,000 miles with no coil problems and the engine is still like new.

The reason the coils fail is because they overheat by lean mixtures due to carbon build up and because the ecu can adjust the dwell and voltage it overworks and then fail. Its too easy to blame Honda but I have never had coil problems in the vehicles I drive and my wife has had 1 problem caused by carbon which they resold the car as Certified. I have also gotten better mpg than Honda said in 60/40 highway getting 2-3 mpg over the Highway on average.

The oil Honda recommends is the oil to use and will last the MM and if for some reason it thickens up it will tell you to change the oil sooner.

 

Hmmm.
I think the 1999 Saab was first with coil paks; what car does your dad have? or you?
2. The ECU has nothing to do with the coil pack; it just signals the coil pack to fire
3. Coil packs wear out from circuitry deterioration not from any combustion condition.
4. The oil or gas quality have nothing to with coil pack deterioration.

All of my cars have had coils (everyone else too) but coil packs, or coils for each cylinder), haven't been around too long.

 

1. Why do you always give me a hard time? My dad has a 97 Toyota Avalon.

2. The ecu signals the coils to fire and gets that info from all the sensors and is continually changing.

3. Coils wear out from excessive heat, vibration and other reasons.

4. Knock is the cause of most of the problems and since oil can cause knock and fouls plugs it could cause problems and so is the fuel which Honda says its tuned for MBT at 91 octane. Regular is at least 91 ron which is the lowest and premium has close to 91 mon which at the other scale but the ecu adjusts the octane from 87 to 96 ron and even higher but probably with no benefit.

Coil packs have been around for a while.

Coil-On-Plug Ignition

I am post this because Volvo is similar to Honda as both systems are CAN systems. This explains the system even though its not a coil on plug set up.


http://www.ohio.edu/people/ridgely/V...nition-OCR.pdf

 

I can add to this thread with yet another. My misfiring didn't cause CEL's at all.

Temporarily corrected with smaller gapped plugs.

Eventually, the problem returned, only much worse and more consistent. I realized it must be coils, since one of the cylinders went out completely shortly after. Then the CEL showed.

To test: simply started the car four times, each time having a different cylinder pack unplugged, until I found one that, when unplugged, did not make the engine run any worse. That was my fried pack.

Solution: Bought a new pack in replaced the diagnosed. Problem hasn't returned in over 50'000km.

 

I concur that that. However, I think there are a number of issues causing everyone's stutter problem. I once replaced a coil pack only to have it fail 100 miles later due to an arc through the body of the plastic body.

When I replaced my engine with a new (used) one I notice lots of carbon on the cylinders and on the head. On the replacement engine there was carbon in between the valve and seat, that I had to remove by tapping on the valves.

To me the mystery persists with carbon buildup being one potential problem and a bad coil plug design.

 

If I give you a hard time its because you propose something not correct.

Individual coils for each spark plug have not around thatlong certainly not in coil pack form.

What has the changing timing have to do with coil pak deterioration? Whether it fies at changing intervals has no affect on the circuitry deterioration; such happens just because it fires.

While vibration can certainly affect coil packs, they are designed to withstand such for the equivalent of 50,000 miles. Only severe impacts from crashes are outside that spec and it isn't designed for 100,000 miles tho it certainly can. Believing they should is incorrect.

Knock has no real affect on the life of coil packs.

Find a listing on vehicles for coil paks before 1999. How close can you get?

good luck and cheers.

 

I know you worked on cars but I have to disagree with you. Knock and lean misfires can cause havoc on the coils and plugs. 90 percent of the problems on this site could be prevented and the coils lasting till at least 110000 miles like Honda says. Fuel and oil do play a part and you know that knock is caused by fuel which produces lots of stress and heat. Even members posted that re-gaping the plugs help because the stress on the coils is reduced and just fires once instead of have a secondary firing or dwell. Other members complained about burnt ignition boots. I am not saying the coils are not bad just that its not normal and is not cause by normal wear or defect until the miles are higher. If it was a defect it would just fail. Every thing members complain about is a miss or hesitation but only under certain conditions and not all the time which I have seen on a 20000 mile Civic which I knew the conditions that got it to that point which was high loads on regular gas..


Here is a COP diagnostic paper. This paper also shows when COP started to be on production cars. http://www.autonerdz.com/downloads/copman.pdf

BTW: I asked my dad if he had replaced any coils on his car and he said no so after 16 years and over 100000 miles the COP are still working fine.