2009 Hemi Misfire only at Idle - JeepForum.com
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post #1 of 37 Old 07-16-2020, 08:32 PM Thread Starter
bumzo1
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2009 Hemi Misfire only at Idle

Howdy, I'm having an issue with my 2009 5.7L with a cylinder 6 misfire but it only seems to do it when idling below about 750rpm. I was hoping to see if anyone had any ideas of where to look next.

The Jeep has 172k miles, about 25k since I replaced the spark plugs with champion copper, and 4k since a 5w20 oil change.

I first noticed the issue when I could feel the engine shake every couple seconds and see the rpms dip as it idled. Its never stalled on me or given a CEL for it. I decided today to finally dig into it and hooked up my scanner (appcar digfca) and noticed the misfires registering on cylinder 6. At this point is hasn't gotten bad enough to actually trigger a CEL but you can watch the misfire counter go up pretty steadily at times. It seems to misfire less as the engine gets warm and completely goes away above 1krpm.

So far I have swapped the coil pack with a different cylinder, but the misfire did not follow the coil pack. I checked the spark plugs in the process and they all look good. I also cleaned the throttle body but that didn't seem to help. My mechanic neighbor came over to help diagnose and he tried spraying carb cleaner around the intake manifold to check for vacuum leaks but didn't find anything. He recommended doing it again first thing in the morning before the engine warms up so I'll do that tomorrow. He then used a stethoscope to listen to the injectors and noticed the Cyl 6 injector sounded slightly more ticky and higher pitched than the others. He suggested running a couple cans of seafoam through the gas tank to really clean off the injectors and see if that helps. I'm going to try and do that this weekend since I'll be driving about 500 miles. If that doesn't work, he suggested to replace the injectors next.

So that's where I'm at, at this point its just an annoyance but would really appreciate if anyone had any other ideas of where to look next. Thanks for your input.


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post #2 of 37 Old 07-18-2020, 10:40 AM Thread Starter
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Ran the seafoam through it and its running a lot better once warm but it still misfiring when cold. I found this youtube video (
) that shows my exact symptoms with diagnosis and repair so I've got a new injector on order. Should be able to swap it next week and hopefully that solves the issue.

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post #3 of 37 Old 07-20-2020, 02:21 AM
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could be the injector or coil pack terminals are wore out and not making solid connection, though not sure why the issue would go away above idle or warm. a few months back i had the cylinder 3 injector terminals go bad, went to start it and instantly had terrible misfires, instantly got a code. after spending hours going over the FSM procedures, like checking the injectors resistance and such, nothing was making sense, continuity was there, injectors good, etc, then while i had my multimeter hooked up I had bumped the injector and noticed that the continuity just disappeared. Then it made sense, gave it some wiggles and and it would go in and out. Now at this point for me I had been having nonstop electrical issues across the board with my 2010 Limited, and this was the last straw so I just started replacing connectors and wiring where I felt. I am a pretty OCD person and many things about the wiring I wasn't kosher with. Didn't like how many of the harness were routed, and such, and this is also my hobby but long story short, most of my engine bay has gotten a refresh. Now similar to what you are saying, I had been watching live data and such on my BlueDriver and over the course of a few months had routinely had reported misfires, likewise not enough to trip a code, and mine would be randomly scattered across the 8 cylinders, I would say on an average drive, 20 mins worth, I would have maybe 1-3 cylinders report between 1-4 misfires. I was at about 30k miles on the NGK coppers, and was about to replace them. Now I did this all at once, so I can't say for certain of which was the culprit, but being as how that injector terminal was wore out...(that happens, honestly I think that these electrical connectors need to be treated like a service item, they can't be disconnected/connected over and over) it made my question if these misfires weren't happening for the same reason...my wiring to the injector and coils looked like garbage too, all twisted up...looked like they had been connected and messed with many times. anyway so I put in a ton of time to research and find the components to make my own pigtails up as I knew there was no way that they should cost what they do, I found the parts for a fraction of the cost and made all new connectors for both the coil packs and the injectors. I spliced them in, changed out the spark plugs to the NGK Iridium's (this is what the NGK website now says FCA recommends as factory replacements for the hemi) and also replaced the grounds that go from the drivers-passenger engine then to the firewall with some much beefier ones I also made myself. The NGK plugs that were in there actually looked good for 30k miles. after that was said and done, things got much better. It has been about 3 weeks now I think, and I hook up my new Autel MS906BT on almost every drive bc well I want to play with my new toy lol, but I have not recorded a single misfire on any cylinder since I did that. my gut tells me that the spark plugs weren't the cause, as they really did look darn good for 30k, and the ground wires were old looking, but not broken, and i had tested ground multiple times over the previous months and always checked out, so it leads me to believe that it was the terminals being wore out that allows for a bit of wiggle and loss of solid contact when under vibration. Also I will note that the connectors could be wiggled a bit fairly easy, or if you grasped it and lightly pulled back you could move it out and in just a touch. After making all new ones, when I pushed them into the coil/injector they went in solid and they dont wiggle even a little bit and cant be pulled rearward at all. Anyway that is my story...I tend to ramble

One thing I will mention is that according to my 2010 FSM Chrysler doesn't recommend using any sort of carb cleaner or such to clean T.B. or intake. My guess is because of the plastic I.M. which if you read the back of the can on most carb cleaners they state not to use on plastic I.M. Also they use the same technique you describe for checking for vacuum leaks, but state to use water/spray bottle to mist it. Lastly the fuel injectors can be checked for resistance, the info below is what my 2010 FSM has, could help you determine if its injector related.

Fuel Injector Coil Resistance Based on Engine Temperature
Temperature ---------Resistance
-20 C (-4 F) = 10 ohms (+/- .6 of an ohm)
20 C (68 F) = 12 ohms (+/- .6 of an ohm)
60 C (140 F) = 14 ohms (+/- .6 of an ohm)
100 C (212 F) = 16 ohms (+/- .6 of an ohm)


Ignition Coil Resistance
PRIMARY RESISTANCE @ 21-27C (70-80F)
0.59 Ohms
(Plus or Minus 10% @ 20C)

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post #4 of 37 Old 07-20-2020, 02:39 AM
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does your scanner have the ability to watch live data or see fuel trims? or fuel pressure? I doubt a fuel pressure issue though since it seems to only be one cylinder. My guess is electrical connector, 1 pigtail is like $20ish find them anywhere pretty much, summit, rockauto(usually cheapest), though if you decide to go my route and do them all, you can make them yourself much cheaper. will need a Molex/AMP style crimper, the one I use was like $20, and the terminals cost like $0.10/ea and the connector bodies are like $4/ea bought them through digikey.com. the wire i get the good quality TXL/GXL high temp automotive wire, this is what you should use, its rated to like 276 or so and its like $5 for 25ft on wirebarn.com. Don't get the crap for sale at your local auto store or fleet farm, etc, as they generally only carry the PVC insulated primary wire which is only good to like 176... I have another thread on here where I linked the exact parts I bought, or just pm me and I can link them again as I saved all the components in my favorites list on the digikey website.

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post #5 of 37 Old 07-20-2020, 08:55 PM Thread Starter
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Thanks for the writeup! I'll make sure and pay special attention to all of the electrical connectors when I swap the injector. My wiring loom definitely needs to be redone on most of the engine but the wiring itself still looks pretty good and the connectors seem sturdy. I'm hoping this solves the issue and if not I'll go into a deep dive into all of the electrical

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post #6 of 37 Old 07-20-2020, 11:36 PM
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yeah no problem, my looms looked terrible too, the wiring was mostly fine except the last 2 or 3 inches of wire at each connector, they were all bent and twisted and such, looked like they had been removed many times, and that just made me uneasy because those terminals wear out, and those wires can break inside the insulation if bent enough. I also had the same issue with the wires at the IAT and ECT sensors as well as the connector at the alternator and the big 16 way connector up by the overflow reservoir. basically all the connectors that might normally be unhooked for a maintenance procedures. I also had found that the RD/GY wire at that 16 way connector was all but broken, and the few strands left of course were green with corrosion. Also the #8 cylinder injector wire was chaffed through the insulation because that injector was tight against the plastic loom and the wires were pinched between the two. lucky it hadn't actually broken through the wires or started to corrode yet. somewhere in a future rebuild. when I can remove all the wire harnesses, i plan to make all new ones, new wires. connectors. the whole deal, and plan to use insultherm for the looms and will have everything looking professional with heat shrink termination and such, but for now I have just been rewrapping the harnesses with Tesa tape, the high heat stuff for the engine bay and the fuzzier type on the interior to cut down any vibration noise. this was about the best i could come up with that allows me to do sections when available, and not have to totally remove all the wiring. One tool I have found to be very handy for cutting off old looms and tape and such is some seam rippers that you find in sewing kits. i flip the ball side down most often so that when slicing down the looms i can prevent cutting into wires accidentally

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post #7 of 37 Old 07-22-2020, 09:31 PM Thread Starter
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Swapped the injector today with a new OEM replacement and it doesn't seem to have made a difference.. The wiring harnesses and plugs all seem to be in good condition. I briefly considered that it may have had a lifter go bad but it doesn't seem like the symptoms match, those people seem to report a loss of power/misfire during high throttle/rpm whereas mine only acts up at low rpm and when cold. I also haven't seen many 2009 hemis or WKs affected by that issue. My mechanic neighbor now suspects a vacuum leak somewhere, maybe in the intake gasket. I'm probably going to do a compression test this weekend but I don't think that's an issue either. I'm starting to run out of ideas...

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post #8 of 37 Old 07-22-2020, 11:09 PM
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On other vehicles I use WD 40 to spray down gaskets when checking for vacuum leaks. It doesn't hurt other components. I have also used WD 40 on vacuum connections.

Have you done a compression test on Cyl 6 and any other cylinder?
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post #9 of 37 Old 07-23-2020, 12:52 AM
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hmm, yeah it could be vacuum related and it definitely could be intake manifold gaskets. they are square shaped and each port has their own, as well as a gasket for the PCV valve and oil fill. I just did mine the other week. This spring I was tracking down many electrical issues as well as trying to figure out why it just seemed off. it was strange, like probably any other person wouldn't have paid attention enough to notice, but I am very OCD and for whatever reason I have a knack for noticing trends, behavior, etc, like if its regarding something I am involved with daily, I get a real good sense of how it normally is or what normally happens. My 2010 just seemed to be getting inconsistent, is the best way I could explain it. like you ever get in one day and just feel like today it has a different attitude? thats how mine was getting. Never had any codes, and I started to watch live data out of curiosity. then while trying to daignose other issues I began watching live data on basically every drive. Had nothing better to do so I would export the data and use excel to trend it, making low, average, and high trends and comparing them against their related components data as well as their counterparts.(specifically talking about the O2 sesnors here, but also other parameters) anyway I started to notice that at time it recorded numbers that did show it to be acting differently. sometimes i would be seeing certain ranges of MAP pressure given the temp, rpm, gear selected, IAT, etc and then I had other days where all other things remaining roughly the same, I could see an oddly different MAP reading. different enough to where I was certain that it was abnormal, no other inputs have changed enough to warrant an abnormal change in MAP. i also started noticing odd activities with O2 sensor readings, thus with fuel trims as well. all the things were quite consistent but randomly would see drops/spikes, or sometimes just be acting overall differently, and then later in the day the next drive would be normal again. I started to think of I.M. gaskets as well, but the water test for vacuum was not helpful, mode 6 would always show random misfires, couple on this cylinder and few on this one, but never consistent. I keep my engine damn clean and when I got it there was some brown oily stains and such in the little "valley" between the I.M. and the valve covers. I cleaned them all up spotless, and slowly over time they started to reappear. the main reason i suspected I.M. gaskets, was this reason, but hell the thing never has code, and the misfires are almost negligible, and the water test doesn't seem to show any clear results. I thought it over and tried to rationalize a diagnosis. Then one day, this is honest to god truth, I was randomly reading some forum posts on a dodge challenger/charger forum based off some google search results, and I stumbled upon this post of a guy talking about how his I.M. on his Hemi had shown signs of leaking fuel. here the brown oily stains I had assumed was oil, is actually more of a mixture, think the brown color is the oil vapor from the PCV system and the fuel vapor form the injectors, mix and thin enough to "leak" out if the seal isn't great. I had always wondered about it but the way it was explained made sense and what he described sounded exactly like what I seen, that magically and very slowly over many months the stains would reappear. that got my attention to keep reading posts and further down I came across a guy that had posted about how he had found his I.M. bolts on his 5.7L Hemi to be loose. He had only like 30k miles on it and he said besides the fuel stains, he just felt like something was off, and so one day he decided to check the bolts and he had found that like none of them were even close to the 105 in/lbs the manual states. said he torqued them back down and went for a drive and he said it was a massive and instantly noticable difference. felt like a whole different car he said. the next post was another guy who said that he had just read that guys post and was like no way, went and checked his and found the same thing, he also had around 30k miles on his as i recall. anyway I read this and I was like GTFO, not even joking I closed the laptop walked out into my garage, took out my micrometer wrench and I put the socket and and extension onto the first bolt and turned the bolt by hand! granted it barely moved, but I made it turn with just my hand and a socket. So I set the wrench for like 80 in/lbs and at that setting only 1 bolt passed, every other bolt turned and turned, I actually panicked a little at first, like there can't be anyway this is happening. my service manual has many incorrect data points in it, maybe 105 in/lbs is wrong, quick look found other 5.7L plastic manifolds being done to 105 on other forums, so I continued in the pattern the manual says, torqued first to 80 out of caution, then to 105. I anxiously got into to the Jeep back it out, I swear just backing it out I already felt like this is not my jeep, my anxiety and now excitement elevated, shut the garage, got in and pulled out of my driveway. i live on a corner, so sitting at the stop sign for a few cars to clear, it sounded different somehow, long story short I hit that gas peddle and I haven't stopped smiling since. It was EXACTLY like the other guys were stating, it felt like a different vehicle. woah man! talk about a cheap performance upgrade! those guys had commented that they found this at 30k miles. I bought mine at 59k and found this at like 80k....I had never felt the Jeep run like this in 3 years of owning it!! that is insane! throttle response, acceleration, pleasant exhaust tones, all got immensely better. And for a parameter that isn't so subjective...gas mileage... before I was averaging about 12.5mpg as a daily driver, most of the driving taking place in small city driving, no traffic jams, but hit stop lights and mostly keep it under 40mph. now I hadn't much questioned the 12.5 average as its a 5.7L Hemi, and always 4 wheel drive, and in town mostly, and I don't drive for gas mileage lol but I had consistently for 12.5 average, and if i reset it on a highway trip I would get into the upper teens, so thats about what they claimed. well after the tightening I ended up averaging 15mpg and trust me I drive it much more spirited now bc I got 3 years of missed time to make up for lol. I have one time managed to get just over 20mpg on a trip, that was a perfect 70 day with no wind and the main road I was taking was brand new pavement and one of those slow windy beautiful roads where you can never hit more than 60mph, so I was just lazy strolling through and somehow broke 20mpg!

so i went back and did the intake gaskets, it would appear all of them were leaking a bit. the gaskets all had a sort of pinch in them for some reason, wish i would have gotten a picture but I forgot. the #7 cylinder was worst, under the I.M. there are some low spots, and the low spots that was next to #7 was like half full of a sticky oil/fuel mix😅 i could tell by the lack of clean surface area where the gaskets mate that they all leaked. every one was stained brown, and every gasket was oily on the bottom side where it mates up. 🤨 just ridiculous. what is crazy to me is that it never set any codes once. idk if its the VVT system or what that it can manage to change the timing that much to compensate for the vacuum leak enough that the system still manages to stay close enough to the programmed ratio and not set off any codes, but holy hell! it still has me awestruck and this was like 3 months ago. Even the braking instantly got better. i could always stop, but always felt like I was trying to stop a tank. Well thanks to the proper vacuum levels the brake booster which is powered by the vacuum in the I.M. now worked much better. simply crazy!

anyway the intake manifold gaskets are like $10 for the fel-pro gasket set which includes the 2 seals for the PCV and Oil fill. it is super easy job, the only "abnormal" thing you will encounter is needing to disconnect the fuel line from the fuel rail. This requires special disonnect tools, and they are cheap. Lisle has a set for like idk $10 i think I paid on amazon. it takes less than a minute to disconnect the line. first you need to relieve fuel pressure by taking out the fuel pump relay ans starting it until it dies, and you can start it again, then you can put a few rags under the connection to catch the fuel, pop the line off. got a few things to unhook and such, unbolt the 10 bolts, remove, clean up. dont be surprised to find a mouse nest under there. make sure to cover the port holes as soon as possible to prevent debris from getting in. if you're to the point and not putsy and meticulous like me, I would say you could have the whole job done in around an hour. cost of less than $30. I put it off for months while i debated if I had a leak or not, for how simple it is, how fast it is, and how cheap it is, I see no reason why anyone who thinks a I.M. leak is possible, doesn't just do it and find out. O yeah that brings me to my original thought, they way the gaskets are designed, you could have it leaking into the underneath of I.M. and that is why the mechanic neighbor didn't detect the leak. it could also be leaking between two cylinders, but think if that was the case you would have a issue with that cylinder as well, but who knows, after all i drove mine for 3 years and never had any codes at all🙄

if you want/need the FSM procedure for removal/install and the procedure for the fuel pressure release and disconnect let me know, I can send them to you some way, email or something.
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Intake Manifold Removed.jpg   Intake Manifold Removed Close up.jpg   Under Side of Intake Manifold.jpg   Intake Manifold Removed with Foam Removed.jpg  
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post #10 of 37 Old 07-24-2020, 10:28 PM Thread Starter
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I picked up a set of the IM gaskets as well as valve cover gaskets and should be able to get them installed on Sunday. Just looking closely around the engine I can see some seepage around most of the manifold so this was probably overdue. Interestingly the problem cylinder looked okay from the outside, but since its in the middle I won't see all around until I take it off. I'm honestly hoping the IM gaskets look pretty bad because I will feel like I have found the issue. If they look decent, I'll probably take off the valve cover and check for failed lifters/worn cam lobes while I have most of it torn apart. I did hear a slight ticking on that side of the motor, but it was inconsistent and I'm pretty sure its just the exhaust leak I've had since I bought it due to a few broken exhaust manifold bolts.

I have been driving it a few times this week and power and fuel economy seems good, well, good for a hemi. I cleared the code earlier this week and have been trying to avoid letting it idle while cold, and the code hasn't come back after a few days and ~100 miles.

I borrowed a compression tester so I'll check that this weekend but I suspect I'm good there.

Thank y'all for the input, I appreciate the help. If I can't get it figured out this weekend, I may give in and take it to a professional.

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post #11 of 37 Old 07-25-2020, 01:08 AM
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yeah no problem, if there is oily/brown stain residue around there I would say it is likely they leak. That leak for mine seemed to be just enough that it robbed me of performance, and just enough to allow the residue to slowly reappear, but not enough to ever throw a code, or even show hints of a leak, no air hissing type sounds, no failing the water spray test, etc. When I took mine off, as you kinda can see above the gaskets were all fully intact, and in place, but the bottoms of the gaskets were oily and slimy and obviously didn't hold a seal. And as I stated above each of them had just a little sort of V shaped sort of pinch in them at the point wher that little cut in the I.M. is at each cylinder. (another smart design feature) that was even more apparent when i pulled up that foam pad that is under the manifold, and found that one pocket by #7 to be full of a half liquid goo. My foam pad was stuck down to the block just a bit, had to peel it off but it stayed in tact. not sure if that was dur to heat or if all that oil/fuel vapor leakage caused it to break down a bit. I had a bit left of a mouse nest to clean up as well, which I had known about before hand, was just able to see the remenants of that from the passenger side. This was actaully the original motivator for me to want to do the gaskets, when I bought it of course the engine bay looked nice with that lame cover on it, which I am not into at all. I think they are stupid, not sure why I would want to trap any more heat in around my vital components, though IMO the factory does a really lazy job of design all the way around. I often wonder if the majority of these engineers have ever actually built/maintained anything, or is the standard engineer just a design man... putting down what looks good on paper. anyway my engine bay was absolutely aweful, dirty all over and oily around the I.M. and then the mouse nest, Keep it all clean goes a long way to helping it breath. If you zoom in on the pictures of when I first got it, you can sort of see the darker looking mess around the I.M. is all the dust stuck to that oily residue....and of course a more recent picture so my standards are represented lol 😂 No way I could ever allow it to look as bad as it did when I bought it.
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post #12 of 37 Old 07-26-2020, 07:21 PM Thread Starter
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Well I dug into it more today and feel like I have less direction now than when I started. I started off by checking compression, I tested the misfiring cylinder (6) and the one next to it and they were both about 200-225 psi so I think I’m good there. Then I went about replacing the intake manifold gaskets and thought I had found my issue. All of the gaskets were leaking at least a little but cylinder 6 had a good layer of crud built up in one of the corners that I thought for sure was my issue. I cleaned it all up really nice, replaced the gaskets, and torqued them down starting from the center and working outwards. Fired it up and no change.. I almost feel like it might even be a bit worse now, still racking up misfires on cyl 6 at idle. Drove it around some and it didn’t get any better.

After that defeat I decided to take a look inside the valve cover, I popped it off and inspected everything and didn’t notice anything that seemed out of place. I had my friend run the starter and took a video of it and all of the valves seem to be opening a similar mount, even had my mechanic neighbor take a look and we both think the lifters/cam is not the issue.

My neighbor still thinks it could be a vacuum leak or possibly a cracked intake manifold. He’s going to try and borrow a smoke machine so we can test it further. I’m starting to wondering if maybe it could be a sensor acting funny and causing this? Crank position sensor, camshaft position sensor, map sensor? I’m Not sure where to go from here..
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post #13 of 37 Old 07-26-2020, 07:54 PM Thread Starter
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Here is the video I took of the valves, it looks like that is not the issue?

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post #14 of 37 Old 07-28-2020, 01:23 AM
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Thats Awesome, I hadn't seen that before! And I am not sure what to say, I would think it wouldn't be sensor related due to it only being on cylinder 6. if one of those sensors were messed up I would suspect there would be issues on that entire bank.

What about MDS?? The #6 cylinder is one that is shut off by MDS. I have very little knowledge past that on the MDS, but the solenoids under the I.M. control them and I wonder if there could be something with that that could cause misfires? I know those are supposed to be a real pain to get out, and seems like you can bet your bottom dollar you will break it to get it out, so I wouldn't go poking around at them unless you have a replacement on hand and you have more reason to suspect it then just my thought of the possibility lol

To me if its just that cylinder it has to be something involving that cylinder alone, the coil pack was ruled out by switching some around, correct? and swapped the injector, and now replaced the I.M. gaskets. Even if it is cracked somewhere, unless it was right next to that port I would think a loss of vacuum should have an effect more like what i seen, randomly spread across multiple cylinders. nothing note worthy in the Valve covers. did you check the wiring from the PCM to the coils, and/or injectors? I am guessing the wiring wont be the problem, but maybe the terminals in the connector at the PCM are intermittent, or double check the ones at the coil/injector? that is the most common thing that I have seen myself when looking for a solution to issues where anything electrical is involved, its very often been the connectors terminals are worn out or very close to it. it can be very hard to tell because the contact points that maintain the connection are inside the female terminal and you really cant tell how they look unless its been pulled out of the connector. if you have a scan tool that lets you see the live data you could watch the info and give the harnesses a wiggle and see if thre is any effect on the readings, or you may even be able to tell by by sound if it starts misfiring more. The fact you think it may have gotten even worse makes me suspect the harness connection even more because that is something you would have pulled off and put back on at least one time since this started, and if that connectors terminals are getting worn out, it will likely get incrementally worse with each disconnect/reconnect you do. if not that the PCM could have an issue? Going off my 2010 wiring the wires for #6 should be in the PCM C2 connector(Orange connector) with the coil control being in Cavity #1 and the Injector Control being in Cavity #4. I would think it would be the same on a 2009, verify wiring color should match. and dont pull them apart unless the battery is disconected(least that seems to be standard in the various procedures involving any PCM work I have come across in my manual)

Mike
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post #15 of 37 Old 08-04-2020, 09:32 PM Thread Starter
bumzo1
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A bit of an update: I took it to a mechanic for further diagnosis and they found compression on that cylinder was a little low, they said 70-80 vs 100-105 for others. I had them take the valve cover off and investigate further and they determine that the exhaust valve on that cylinder wasn’t closing completely. They said they needed to remove the head to investigate further but seemed to think it was a sticking valve lifter that wasn’t allowing the valve to close all the way. I had them stop at that point, they quoted me worst case scenario of replacing all lifters and the cam and said it didn’t make sense to continue digging unless I was willing to go all the way.

It’s not quite the diagnosis I expected, they were sure it was an issue with the valve not closing 100% vs the common hemi lifter failure where the valve doesn’t open. They didn’t seem to think it was a bad valve spring but didn’t rule it out either.

if it truly is an issue of the valve lifter sticking intermittently, my neighbor suggested doing an oil treatment like marvel oil and then changing the oil with something like redline. Changing the oil did seem to help some so it seems this could help some more?

At this point I think I will try the oil treatment next, and if that doesn’t work I’ll probably remove the head myself and get a clear picture of what’s going on. I’m really hoping it is just the lifters on that side that would need replacement and not the camshaft as well. I should get my uoa back in the next week or two and that should give me a good idea if the camshaft is wearing.

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