When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'm lost then.... how do you know if misfired 34 times? You can see what cylinder is misfiring under live data.
So I am working with his new tool. I don't yet know how to do everything with it yet though. I ran a test with a misfire counter but I have not figured out how to view individual cylinders.
Update:
I went out and checked again this morning with Forscan and picked up a Pending code.
P0303.
Code: P0303 - Cylinder 3 Misfire Detected.
Status:
- Pending - malfunction is expected to be confirmed
Module: On Board Diagnostic II
Diagnostic Trouble Code details
Cylinder 3 Misfire Detected.
Ignition System
Fuel System
This DTC may be caused by :
Blocked kinked or crushed fuel lines
Fuel contaminated
Evaporative emission control system malfunction
EGR system fault.
Base engine fault
Check for any other codes that may cause a misfire.
Last edited by SportsmanJake; 10-27-2017 at 08:48 AM.
If I have some time this evening on the way home I'll get you the PID's to look at. It should also tell you if you have any pending DTC's on the DTC side.
Edit: You posted about the same time I did. Have you pulled the plug on cylinder 3 at all? I'd suggest doing so and taking a look at it. Check the gap in particular. While 25k miles is a bit low for these plugs it may be a bad plug or connection. The spark plug chart can give you an idea how the engine is running:
So I just pulled number 3. It had a bunch of gunk around the top. The gap was still good.
I used a little compressed air can and blew out the cylinder.
I gapped and hand threaded a new plug on and torqued it to 25 ft-lb. No anti-seize.
I put a little dialectic grease on the inside of the coil.
Started it up and still misfiring like before. I still don't have check engine light DTC yet even though it is misfiring a lot at idle.
Originally Posted by Michael_in_DE
P0303
Faulty spark plug 3 Clogged or faulty fuel injector 3
Faulty ignition coil 3
Fuel injector 3 harness is open or shorted
Fuel injector 3 circuit poor electrical connection
Ignition coil 3 harness is open or shorted
Ignition coil 3 circuit poor electrical connection
Insufficient cylinder 3 compression
Incorrect fuel pressure Intake air leak
After looking up your code, I can see the injector is the second item listed. The only other possibility is that you disconnected the injector connection clip or broke it. (I'm not judging you, I break them all the time) and vibration has broke it loose again. Worst case scenerio, you put out $15 for an injector. That might be my next move. Are you still getting the P0303?
BTW there are entertaining videos on youtube on how to clean your injectors with cleaners and and a battery. I think I would spend less time and money just replacing it.
The injector connection could be bad. Or the injector itself could be bad.
I guess I will buy this and give it a try for cylinder 3. I really didnt want to take the fuel rail off.
edit: 1:48 pm
I went around and made sure each coil plug and injector plug was properly connected.
Just took it for a short drive and i think I lost a couple fillings. Shaking like I have never experienced before. Still no DTC.
Last edited by SportsmanJake; 10-27-2017 at 01:51 PM.
Well, I haven't read page 1 and 2 yet, so if I'm a little off....
That's number 3?
The plug, - amazingly the burn looks close correct for THESE modulars...a little whitish. That's how these engines run, a little on the lean side. Okay, it's a little too white I guess. Looks goofy because the rest of the plug that sits in the cylinder is so clean lol. BUT, - for it to cake up carbon like that it had to be either cross threaded or loose in the hole. I'm not sure how else that could happen. Yea, it looks like THAT plug was firing...at least some of the time.
Strange one for sure ..different lol.
But yea, you can't really go by those plug charts for a modular plug burn. Well you can if you throw a little white in the mix. These plugs when all is well should show lean...the modular burn. Also, if you say, add a gotts mod or reconfigure your exhaust, -they run even leaner and that reflects one the plugs...even whiter in color. Since this entails increasing intake and exhaust and the bi-product of that with the original tune is mixing lean (even more so). Not dangerously lean, your still within PCM programmed parameter margins. Side effect is even whiter plugs lol. Just a point of info.
If you watch the mode 06 test counts, you will often see low results that come and go.
Your misfire monitor must run to give a code. It doesnt run until certain conditions are met. Including fuel tank level, and deceleration cycles that provide data for Keep Active Memory. If you disconnected your battery, you may not get a code until the conditions are met again. Several 65-40 deceleration cycles without touching brake often dont happen without doing them specifically.
I went thru a period on my 2003 where the mode 06 $53 misfire count data was not changing, Im talking over weeks of watching it, and I went looking for reason why. I drive 50 miles/day mixed interstate, and stop and go, so drive cycles should complete.
If the KAM profile correction factors have not been learned thru the three 65-40 mph decelerations without braking, it apparently doesnt run the misfire monitor. Or if fuel level is too low. This is a very unusual deceleration that I would never do unless done intentionally. Even on an exit ramp people get pissed behind you just rolling down to 40.
After intentionally doing the decelerations on the interstate, and making sure I had over half tank gas, mine started running again and mode 06 $53 started changing everytime I checked it. Despite saying 15% fuel level, Im not sure that was correct.
I dont know why I needed to do this again, it had been done in past and had not disconnected battery or such.
When are the KAM correction factors lost?? I think when you reset pcm/codes or disconnect battery. Its part of the drivecycle. Scan tool can show emissions ready...even if this isnt complete apparently, because mine did. I also drove over 1500 miles once because drive cycle wouldnt complete without >170F, and tstat was stuck open, only getting to 168 or so.
Well, you won't want to hear this but the oil in the plug wells are two-fold trouble.
1. Leaking valve cover gaskets. Which is not great, but on it's own not detrimental to functionality.
2. If enough oil gets into the sparkplug wells at a liquid state it can cause a misfire, starting at higher RPMs, and will get worse as the well fills up.
That is what all that gunk is on the spark plug you pulled. Dried/cooked oil. BUT you can see the oil level on the plug, and I don't think that is enough oil to cause a misfire. On that plug at least. On another car I worked on the well was compltely filled, which caused a misfire) I'll let others confirm this oil-in-the-wells-=misfire issue.
BTW this might be why the problem went away after your last sparkplug replacement. The wells drained into the cylinders, (great I'm sure thats good for it) and it took a while for oil to accumulate again to cause a misfire again.
I DO NOT advocate you replace your valve cover gaskets. I am sure that is an intense lengthy job, and I would seek a professional opinion before doing so.
If you were inclined to test the theory, you could use a suction tool and needle nose to clean the wells and run it. Thats what I did, and it confirmed it for me. (on a different vehicle I had)
10-26-2017, 10:12 PM
