Jump to content

  • 2 Pages +
  • 1
  • 2
  • You cannot start a new topic
  • You cannot reply to this topic

Does your S2k have a Misfire? A Misfire Manifesto

#1 User is offline   Slows2k 

  • View gallery
  • Group: Former Moderator
  • Posts: 35,112
  • Joined: 06-September 02
  • Gender:Male
  • Location:Mother F'in TN
  • Country: United States
  • Interests:Peace on earth, Goodwill towards man. Repeal the NFA and GCA

Posted 11 May 2011 - 11:22 PM

Misfires in S2k's fall under a few general rules.

1. A Cylinder specific misfire. If you have one you will see a specific P0301 to P0304 denoting the Cylinder.

2. A random Misfire P0300, It is not cylinder specific., but multiple cylinders.

3. A Multi cylinder misfire, that is more than 1 Cylinder misfire DTC's at the same time.

These are all SAE defined OBDII DTC's. A Cylinder 1 misfire on a S2K or and any car built for the US market since 1996 is required by law to define the DTC the same way. A P0301 on a BMW or a S2K is still a cylinder 1 misfire. Occasionally a cylinder specific misfire is accompanied by a P0300 random misfire or a p1399 temporary misfire DTC. If you let the car run long enough with a P1399 is turns into a permanent DTC, the P0301 to P0304 or a P0300.

Cylinder #1 is closest to the radiator, Cylinder 4 is closest to the firewall. Cylinder order is 1-2-3-4.

I'd like to bring up the ability of the PCM to correctly identify a misfiring cylinder it IS NOT always able to accurately identify the misfiring cylinder, especially if there are more than 1 cylinders misfiring.

A cylinder specific misfire often troubleshooted by moving components, Moving coils, plugs and injectors are all valid tests. If the misfire moves with the component replace the part. You can still have a wiring harness or PCM issue and not a mechanical problem.

If you have a misfire code that is not effected by moving a external component such as a coil, plug or injector The most likely cause of a misfire is either low compression, or valve train damage. = An internal engine problem. On rare instances a wiring or PCM could still be a cause.

If you have multiple cylinder misfire codes it is usually not a component. Multiple component failures are rare.
If the misfire just started after you put gas in and now barely runs it's usually a fuel quality issue.
Cylinders that have low compression misfire. Cylinders with normal compression #'s rarely have high leakdown rates. Normal S2K compression test numbers I have found on cars in service are 200-220Psi.

If you see under 200psi, there is a good probability you will also see a high cylinder leakdown number.

Leaking piston rings, scuffed bores, bent valves and burned valve seats are causes of high leakdown and low compression.

Leaking or burned valve seats has become much more common with higher mileage multiple owner cars than it used to be.

If you have the Freeze frame data from your car, this is only 1 frame of data when the DTC was set. It gives you a basic information of the operating conditions of the engine. Most inexpensive scan tools provide a minimum of data, the more expensive the tool, the more complete the data is.

Fuel trim in Freeze frame data is the adjustment the PCM is using to get back to a 14.7:1 ratio. Since Catalytic converters need to be either slightly rich or lean from 14.7:1 to reduce NOx, an HC and CO from the exhaust the Fuel trim #'s will always be changing when watching on live data from the PCM. The freeze frame is 1 data point at the time of the misfire. Different scan tools will display Fuel trim differently, some use 100%, some use 0 to start. 105 or 5% would be lean from 14.7:1, The PCM will be increasing fuel to the injectors. 95 or -5% would be rich or reducing fuel to the injectors.

Misfiring cylinders do not burn the fuel being injected into them. It is not unusual to see rich Fuel trim #'s The fuel trim is calculated directly from oxygen sensor feedback. If there is excess oxygen in the exhaust the engine did not burn the fuel injected into it. PCM sees the rich condition and reduces fuel.

Here lies the rub, lean cylinders misfire too. You can have a lack of fuel and and get a misfire, and the PCM will add fuel. This is why it is very easy to misread fuel trims to determine the cause of a misfire.

My advice, don't worry with Fuel trim #'s, they are only a small part of the big picture.


Step 1. Swapping components( plugs, coils, injectors) If the Spark plugs are black and sooty there is a source for this, you will need to identify it. low compression will result in a sooty or wet spark plug. If the plug fouled replace it Fouled plugs do not work.

Step 2. If the misfire did not change with a component you need to investigate are the components working in the 1st place? They make test spark plugs that plug into a coil, I highly recommend picking one up. Special tools may be required here! if you are in over your head, STOP. Do not break your car worse. Please do not set your car on fire, or cut an engine harness trying to diagnose it. Butchered engine harnesses make Mechanics very angry. :cursing: We charge extra to unf@#k what someone has has f@#ked before we can continue diagnosing your car. You can skip to step 3, but if you don't eliminate all of the possibilities in step 2, your car will still be broken.

Step 3. Perform a compression test, followed by a leakdown test if the compression is low. The leakdown will identify where the compression loss is from. Either the rings and bores, or the valve train.

A word on the random misfire guys and gals,

Your car that sometimes runs ok, but also runs like crap at times. You could have a component failure, or an internal engine issue. Often replacing some parts happens during the diagnosis since your issue comes and goes. Wiring connection issues are rare on a Honda that has not beed screwed with. Unfortunately S2K's have a very high rate of being screwed with. if you had a VAFC, Emanage, an injector swap or a Yellow box, start there. Bad connections often do not present themselves the same way all the time. If you have gone through the component swap dance and nothing has changed, go to step 3.
Whoretech'd twice ;)

R.I.P. JS.


Posted ImagePosted ImagePosted ImagePosted ImagePosted ImagePosted ImagePosted ImagePosted Image

Posted Image

#2 User is offline   JDMQuip 

  • View gallery
  • Group: Guest
  • Posts: 3,440
  • Joined: 09-May 06
  • Gender:Male
  • Location:San Diego, CA
  • Country: United States

Posted 12 May 2011 - 12:31 AM

Very good to know. I'm having a misfire gremlin currently in cylinder 1. Motor was rebuilt and my mechanic (who also owns an S2K) can't pinpoint it quite yet. We've seemed to narrow it down to FUEL rather than ignition. We swapped coil packs, plugs and even went as far to pressurize the injectors and run some cleaner through them. The misfire seemed to get worse AFTER the injector cleaning which led us to believe it's fuel related since the coilpacks and plug swap didn't do much difference.
HardtopGuy.com 4.77 Gears, S2K weight loss program, JIC Coilovers, Berk HFC.

#3 User is offline   Slows2k 

  • Topic Starter
  • View gallery
  • Group: Former Moderator
  • Posts: 35,112
  • Joined: 06-September 02
  • Gender:Male
  • Location:Mother F'in TN
  • Country: United States
  • Interests:Peace on earth, Goodwill towards man. Repeal the NFA and GCA

Posted 12 May 2011 - 12:47 AM

I've replaced several faulty injectors, mostly AP1 cars. Move the injector to different cylinder and recheck for the DTC to change. RC engineering can even clean and flow test stock injectors for a fee.

#4 User is offline   Slows2k 

  • Topic Starter
  • View gallery
  • Group: Former Moderator
  • Posts: 35,112
  • Joined: 06-September 02
  • Gender:Male
  • Location:Mother F'in TN
  • Country: United States
  • Interests:Peace on earth, Goodwill towards man. Repeal the NFA and GCA

Posted 20 May 2011 - 01:10 PM

:bump:

#5 User is offline   raymo19 

  • View gallery
  • Group: Gold Member
  • Posts: 12,472
  • Joined: 14-March 05
  • Gender:Male
  • Location:Flintstone GA
  • Country: United States

Posted 20 May 2011 - 01:15 PM

AEM 1052 - don't have to deal with any annoying codes. :LOL:
Are we there yet?
Dark Fader
Spread your arms and
Hold your breath and
Always trust your cape - Guy Clark

#6 User is offline   TheLast13 

  • Group: Guest
  • Posts: 1,797
  • Joined: 12-July 08
  • Gender:Male
  • Location:Akron, Ohio
  • Country: United States

Posted 20 May 2011 - 03:48 PM

Great write-up!

#7 User is offline   Slows2k 

  • Topic Starter
  • View gallery
  • Group: Former Moderator
  • Posts: 35,112
  • Joined: 06-September 02
  • Gender:Male
  • Location:Mother F'in TN
  • Country: United States
  • Interests:Peace on earth, Goodwill towards man. Repeal the NFA and GCA

Posted 20 May 2011 - 11:55 PM

View Postraymo19, on 20 May 2011 - 01:15 PM, said:

AEM 1052 - don't have to deal with any annoying codes. :LOL:



Couldn't detect the misfire if it wanted too either :stick:

#8 User is offline   raymo19 

  • View gallery
  • Group: Gold Member
  • Posts: 12,472
  • Joined: 14-March 05
  • Gender:Male
  • Location:Flintstone GA
  • Country: United States

Posted 21 May 2011 - 02:26 PM

View PostSlows2k, on 20 May 2011 - 11:55 PM, said:

Couldn't detect the misfire if it wanted too either :stick:

Yep - at least I don't have the annoyance in the mean time. :LOL:

#9 User is offline   raymo19 

  • View gallery
  • Group: Gold Member
  • Posts: 12,472
  • Joined: 14-March 05
  • Gender:Male
  • Location:Flintstone GA
  • Country: United States

Posted 23 May 2011 - 05:02 PM

:bump:

#10 User is offline   TurboViper 

  • View gallery
  • Group: Community Organizer
  • Posts: 1,629
  • Joined: 16-August 06
  • Gender:Male
  • Location:Murrieta, CA
  • Country: United States

Posted 23 May 2011 - 08:28 PM

Good information! :thumbup:
Posted Image Posted Image
Infinite Motion (San Marcos, CA)
My Youtube (Track Videos)
- “If you hire only those people you understand, the company will never get people better than you are. Always remember that you often find outstanding people among those you don't particularly like.” - Soichiro Honda
- "I was already on pole, then by half a second and then one second and I just kept going. Suddenly I was nearly two seconds faster than anybody else, including my team mate with the same car." - Ayrton Senna
SD Events (Meets & Track Days)


"Due to the fallout of the 2008 Credit Crisis and the recession it brought, Honda, struggling as every other manufacturer, has decided to bring an end to the slow-selling S2000 by MY 2010. But before that, Honda has released a special version for Europe called the Ultimate Edition. The final S2000 will feature exclusive "Grand Prix White" paint, a red leather interior, color-matched stitching and numbered doorsill plaques. Underhood, it retains the 2.0-liter VTEC-equipped four-cylinder putting out 237 hp and 153 lb-ft of torque through a six-speed manual transmission, but benefits from a new set of wheels and an optional hard-top."

#11 User is offline   BEETROOT 

  • Group: Guest
  • Posts: 176
  • Joined: 22-February 05
  • Gender:Male
  • Location:Chandler, AZ
  • Country: United States

Posted 23 December 2011 - 08:31 PM

My AP1 w/ 91k on it just had CEL and codes 1399, 1301, 1303, 1304. Solved by step one in this write-up, the spark plugs were bad. Thanks to Science of Speed for figuring this out for me :)
2002 s2000 - gone
2002 z06 - I/H/E
1930 Model A rat rod

#12 User is offline   ddess 

  • View gallery
  • Group: Member
  • Posts: 1,083
  • Joined: 13-August 06
  • Gender:Male
  • Location:Long Beach, Ca
  • Country: United States

Posted 23 December 2011 - 08:42 PM

So I just installed my new exhaust with a TP. I get off my block and I get the blinking engine light and the engine was missing. I push it back down my street and pull the plugs. They all look fine, no foul. I have the P1399 code. Could I have not tightened down the O2 sensor enough to trip this cel?

#13 User is offline   ddess 

  • View gallery
  • Group: Member
  • Posts: 1,083
  • Joined: 13-August 06
  • Gender:Male
  • Location:Long Beach, Ca
  • Country: United States

Posted 24 December 2011 - 05:05 PM

^^^^^Ok fixed it. I put new plugs in and then swapped all the coil packs from another car. Cleared the code and it purrs. Let it warm up then took if for a spin. Perfection, no cel or misfire. Then I swapped back in the old coils on at a time until the misfire appeared. It was only one pack, Picked one up at the dealership. (Not cheap) now I'm back in business!

#14 User is offline   drshottest718 

  • Group: Member
  • Posts: 231
  • Joined: 13-January 09
  • Country: United States

Posted 21 April 2012 - 06:28 PM

my ap1 with 43k miles had been smelling like fuel inside the cabin for about a week or so. I would open the hood and look/smell for fuel leaks and saw none, but oddly enough there was a strong odor inside the car.

Last night the car threw a CEL and started idling funny. I ran the scanner on it and it said misfire cylinder 3.

Checked all coils for spark, all were good. Cylinder 3's spark plug was black as hell and wet with fuel (which leads me to believe the injector is at fault....right?)

Auto parts store was closed so i couldnt get new spark plugs and a new injector. Am i on the right path?

I'm thinking maybe that one injector has been leaking, causing the smell of fuel, and might have wet the plug as well causing the misfire? I hope its that...
Posted Image

#15 User is offline   Slows2k 

  • Topic Starter
  • View gallery
  • Group: Former Moderator
  • Posts: 35,112
  • Joined: 06-September 02
  • Gender:Male
  • Location:Mother F'in TN
  • Country: United States
  • Interests:Peace on earth, Goodwill towards man. Repeal the NFA and GCA

Posted 22 April 2012 - 05:35 PM

What DTC do you have?

#16 User is offline   drshottest718 

  • Group: Member
  • Posts: 231
  • Joined: 13-January 09
  • Country: United States

Posted 22 April 2012 - 08:04 PM

View PostSlows2k, on 22 April 2012 - 05:35 PM, said:

What DTC do you have?



303...or whichever one denotes cylinder 3...

#17 User is offline   DutchyFutch 

  • Group: Guest
  • Posts: 101
  • Joined: 02-March 14
  • Gender:Male
  • Location:Boston
  • Country: United States
  • Interests:S2000, Fixing cars, Fixing sneakers, Building computers

Posted 15 September 2014 - 10:09 PM

I have no spark in cylinder 3 from the coil itself. No idea why. I've changed coil packs. spark plugs and even cut the wire for a new one.... :confused:
MY 00' S2k 45k miles owner since may 17th 2014.
Posted Image

#18 User is offline   Slowcrash_101 

  • Group: Guest
  • Posts: 1,569
  • Joined: 10-July 13
  • Gender:Male
  • Country: United States

Posted 16 September 2014 - 05:35 AM

I don't have any DTC's no pending DTC's no CEL's(checked with my teacher's $3,000 Honda scanner) replaced the coil packs, the spark plugs(they were light brown at the threads with grey tips), cleaned IAC, replaced O2 sensors, compression and leak down are good, and yet my engine has a slight miss during idle. It idles fine otherwise, very smooth, but I can hear a slight miss that happens randomly(car exhaust burbles normally but randomly it sounds like one cylinder doesn't fire). I checked all the wires, and coil pack connections, they all seem to be doing their jobs. The problem is most prevalent when I first start the car, once it's up to operating temperature it still does it but it's much less frequent. Is this normal? It's a 2002 AP1 with 130k miles, I have a Berks 70mm header back, and a CT icebox, filter was replaced in December of last year, and I cleaned it two months ago.

This post has been edited by Slowcrash_101: 16 September 2014 - 05:40 AM


#19 User is offline   Hernandoe7 

  • Group: Guest
  • Posts: 17
  • Joined: 02-June 14
  • Country: United States

Posted 16 September 2014 - 11:03 AM

awsome write up, just what i needed as just 3 days ago, my CEL light came on and i think its most likely due to a misfiring cylinder like last time :/ spending like 5k on this car just to get it running makes me really regret buying it now..

#20 User is offline   lobuck 

  • Group: Guest
  • Posts: 176
  • Joined: 15-November 10
  • Country: United States

Posted 23 September 2014 - 03:27 PM

I recently changed my car to a 70mm berk and a couple days later got a cel. Says it was 1399 and 0303. I changed the plugs and swapped coil pack 3 with 2. Now I get code 1399, 300, 301, 302. Any thoughts. Was thinking to tq down the plugs more and try some fuel cleaner.

Btw, plugs looked dirty, plug one had oil on top which might be from valve gasket.

#21 User is offline   Slowcrash_101 

  • Group: Guest
  • Posts: 1,569
  • Joined: 10-July 13
  • Gender:Male
  • Country: United States

Posted 23 September 2014 - 04:43 PM

You might be getting oil past the spark plug tube seals.

#22 User is offline   lobuck 

  • Group: Guest
  • Posts: 176
  • Joined: 15-November 10
  • Country: United States

Posted 24 September 2014 - 03:21 PM

Next step is a valve adjustment and I'll replace the gaskets then.

Replacing a cat won't cause this right?

#23 User is offline   Slowcrash_101 

  • Group: Guest
  • Posts: 1,569
  • Joined: 10-July 13
  • Gender:Male
  • Country: United States

Posted 24 September 2014 - 07:52 PM

not that I know but a bad 02 sensor can

#24 User is offline   JesseW 

  • Group: Member
  • Posts: 35
  • Joined: 31-August 14
  • Country: United States

Posted 24 September 2014 - 09:15 PM

check the valve retainers also. i bought an engine really cheap the guy removed with low compression and a misfire code.... ended up the retainer had cracked and the valve touched the piston just enough to barely bend it.....(no marks on the piston or valve, just barely bent but enough to only have 90 psi of compression) i put on another head that i had and it fixed all the problems with that engine.

#25 User is offline   lobuck 

  • Group: Guest
  • Posts: 176
  • Joined: 15-November 10
  • Country: United States

Posted 25 September 2014 - 02:08 AM

Thanks, the o2 seemed good before I changed the cat. Not getting any other code besides misfire. Even added the o2 defouler.
I'll check the retainers but guessing it should be ok as they were replaced a couple years ago with ap2. Hope it's just valve adjust.

Ads by Google   S2KI

Share this topic:


  • 2 Pages +
  • 1
  • 2
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users