This has been a great help for me to fix my misfire. I had lean misfire when the vehicle is cold (AFR gauge read ~15/16 when misfire occurs).
Naturally, I thought it was the injector that's acting up, but it turned out to be the coil packs. Coil packs replaced and the vehicle no longer has the problem.
Hope this helps others who are trying to fix the issue.

Jay

 

I've been experiencing CEL and misfire codes on Cylinders 1, 2 3, 4 and random on my 03 with 130K miles for about eight months. I've taken it to my local shop that specializes in Hondas and after a leak down test and compression test, it was discovered cylinder 2 results were low and that I have a bent valve. I know that I have had some high revs and some misshifts in my day so I am to blame despite being current on maintenance.

The shop is recommending a rebuilt head, new timing chain, etc to the tune of $3800 - $4200 for parts, head rebuild and labor with best guess at $4,000 . I'm not unsure about getting the work done as I love the car and have no plans of getting rid of it anytime soon, but wanted to ask for advice on what else should also be on the lookout for while they have the engine disassembled and I'm putting up the money into it. Thanks!

 

Just to add another thank you...

I had P1399, P0301 and P0303. Decided to start with a valve adjustment and the valves were way out of spec. Cylinders 1 and 3 each had an exhaust valve that had virtually no play. I've got an '06 and the valves had never been adjusted.

I can't explain why 1 AND 3 decided to have a problem at the exact same time, but no CEL after driving it today.

 

Exhaust tighten much faster on the 06+. They are responsible for burnt valves. Keep an eye on it!

 

Heyy guyss I need help cause I m going crazy . I have an s2k ap1 and I have installed a stereo and after I have noticed some misfire and then I have installed a gps and the misfire get worst. Then I have cleaned the throttle valve and the throttle bottle but still for nothing and I have changed the spartin plugs and coil and gor one day it was fine but the misfire returned and now I have cleaned the injectors but still for nothing . What do u suggest plss its from the current cause when I installed the stereo begins the misfire ??????

 

Heyy guyss I need help cause I m going crazy . I have an s2k ap1 and I have installed a stereo and after I have noticed some misfire and then I have installed a gps and the misfire get worst. Then I have cleaned the throttle valve and the throttle bottle but still for nothing and I have changed the spartin plugs and coil and gor one day it was fine but the misfire returned and now I have cleaned the injectors but still for nothing . What do u suggest plss its from the current cause when I installed the stereo begins the misfire ??????

 

So I am continuing a discussion I began here. And thanks again to the UTH readers who responded so quickly.


I did a compression test this past Friday night and came up with these numbers:


Cyl #1: 135
Cyl #2: 220
Cyl #3: 235
Cyl #4: 225


Whoa, #1 is pretty bad, and it was the first cyl. to throw a misfire code. Sat. I pulled the valve cover and checked the #1 clearances. I backed the exhaust off about an hour and tightened the intake just a hair. I was hoping this would cure my problem but in the back of my mind I was thinking that it was such a small adjustment and why only cyl #1 if I had set all the other valve clearances with the same "drag" on my last adjustment? Put everything back together (yeah, I started to check for cracked retainers, but then I was distracted by my children, so I only checked the exhaust side) I then warmed the car back up and did another compression test with my fingers crossed, and came up with these numbers:


Cyl #1: 135
Cyl #2: 230
Cyl #3: 235
Cyl #4: 235


The CEL has still not come back on yet, but now, unfortunately, I have bigger problems with compression in #1. This is quite baffling to me, like I have stated before I have never had a mechanical over-rev, kept obsessive maintenance, never had a misfire, and the car seems to be running strong. This all makes me wonder just how long compression has been low in the #1 cyl?
My next step will be to pull the valve cover back off and check all my retainers and take the time to check all cyl. valve clearances, then I'll make an appointment for a leak down test at the nearest trust-worthy Honda dealership. That's the real kicker for me, I dread taking my S into the shop for anything, I've always done all of my own work on this car because of many bad experiences in the past with dealership service departments.


Please, any insight into what might be going on would be much appreciated!

 

Why not do the leak down test yourself if you don't like the dealership? You seem able bodied enough. You just need an air compressor and a leak down tool.

How many miles are on the car? How many of those Mike's have you owned it?

 

Leak down myself? I never really thought of that (never had the need to get one done, don't know what it entails), would you have a good link to that? 66500 miles on car, I'm the original owner, so I'm the only fool to blame for it's woes

 

See the thread in my signature about POV DIY videos. The leak down test is a recent addition. If you have done your own valve adjustments and you are familiar with TDC and removing the valve cover it should be a peice of cake