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Found 50 results

  1. I don't know much about this system, how it operates, the stress that is placed on the lifters during cylinder deactivation. How common is this failure? Been watching some YouTube videos on the repair and it's very labor intensive...heads have to come off, etc. I see that you can buy the entire kit (lifters, gaskets) for around $500. Have a friend that told me...just change your oil, you'll be fine. The number one cause of this failure is neglected maintenance. That true? Or is it an inherited problem with the design of the system? The system came out in 2007, there must be some improvements made to it since then, no? I must say that the AFM is allowing me to get some excellent fuel economy out of a full size truck. So is this a common problem, or are there people with 200,000 on these trucks that never had an issue with it?
  2. Installed a 3" Motofab level on my truck last weekend. Rear is stock. Added 20x12s with 33x12.5 tires. Minor plastic and metal trimming, no rub at all. Smoked my tails and 3rd brake light. Will smoke my front turn signals and corner markers this weekend. Will also vinyl wrap the chrome mustache on the bumper, unless someone wants to trade for all black. Going to do a muffler delete (leaving resonators) and clamp the flapper valve open, will also add a Range AFM delete. Has 30% tint now, will eventually do 15% this summer. Will post more pics as I make progress.
  3. RX Speedworks Catch Can

    I have an RX Speedworks catch can that i had installed on my 2016 Sierra. It attaches using the bolt for the brake fluid. Has the clean side separator that I used as well but not included in the pics but can provide more pics upon request. Will work on other vehicles. My price is obo shipped. TIA. https://www.rxspeedworks.com/product/gmc-sierra-oil-catch-can/
  4. Does anyone know if the AFM problems were solved? Should I be concerned with the AFM in my new 2016 5.3L Silverado? thanks!
  5. I recently did a dod delete on my 2007 suburban. 6.0 200,000 miles. I thought the problem was the afm lifters being that there was a tick at highway speeds. I only had a tick at highway speeds. If I drove on the street I would never get the noise. As soon as I held a steady speed on the highway I would get what sounds like a lifter tick. The dod delete work was done by a Preformance shop. I do not think that dod was the problem. If I hold the throttle steady at 2000rpm while in park I can get the tick to come on. After I let the engine idle about 2-3 minutes the tick goes away. As soon as I hold the rpms back up it will come back and repeat the process. No loss of power while this is happening and no other sounds. Oil pressure is about 10-15 at idle and close to 40 while on highway. I would greatly appreciate any help.
  6. Hello All, This is my first time posting in this forum!! Just bought a DiabloSport Itune I3 Platinum Programmer. I am looking for some decisive direction as well as suggestions on the best parameters for tuning my truck with the I3 Platinum. Specs of Truck: 2014 Silverado Z71 LTZ 2WD Crew Cab Rough Country leveling kit installed 33" x 12.5" x 22" Nitto Terra Grappler G2 A/T tires 5.3L Ecotec flex engine K & N Cold Air Intake installed Gentle 46k miles I RUN 93 OCTANE IN THIS TRUCK Being a 2 wheel drive (It Does have the Z71 package, Rancho shocks, etc...) Obviously it raked in the front. First thing I did was put the K&N CAI on and it was like a rocket in Manual 5 gear mode, when I shifted through the gears myself. After leveling kit and 33's with aggressive tread, it was complete garbage. No power, confused shift points, almost like missing. Just a hot mess. So I bought the Intune I3 first, rather than switching to a 4.10 gear (which I may do later). Already turned off AFM and that was immediately effective. Also, 15% throttle boost. Can anyone suggest the best parameters to make this bad boy get up and GO!!?? I would like to know if there is a good idea on what ECM and TCM adjustments should be made to not only get that stock power back on 33's. But also get good fuel economy. The standard Diablo Flex, Jammer and 91 tunes don't seem to help a whole lot. Still bogs down and takes forever to get through 1st and 2nd gear. Anybody know about these tuners on a 14 Silverado with 33's?!?!?! Please help!!! Alan
  7. Chevy passed out a 2019 Silverado information book to journalists during this week's media drive. I'm working on scanning the entire thing and sharing it here. There's a lot of information packed into this flip book. I thought the most interesting was the engine line up and an AFM vs DFM diagram. This is the best comparison blowout diagram I've seen so far. Here's the four pages related to the engines.
  8. Hello everyone new to the community and new to Chevy trucks. I'm looking to purchase my first Silverado in the near future but after researching the current gen Silverados I keep seeing how afwul afm is in these trucks and how in extreme cases it can lead to engine failure. Can someone explain to me exactly what what the problems are that owners are seeing with this technology and my big question is, have a lot of the issues been worked out or even resolved in the 2017-2018 models? Are the problems with afm severe enough to not make it not worth getting a new Silverado? All the bad things I am reading are really pushing me away from buying one . Any and all information is welcome ! Thanks guys !
  9. Hey guys I’m new to the forum but I’ve been a long time subscriber since I bought my 14 Sierra new in feb 2014. So I’ve read lots of horror stories on the site and I thought I’d tell you guys about my experience. A few weeks ago over 5r holidays, my girlfriend and I were returning a uhaul after moving and she was following in my truck, she called to say that the check engine light was on and the truck had reduced power. We dropped off the uhaul and I hopped in and could tell it was misfiring and had a rough idle. I took it to my local mechanic and he told me cylinder 4 was misfiring and he tried a coil pack but that didn’t fix it, he did a compression test and it was holding compression but he told me this was gonna be a bigger problem. luckily I still had powertrain warranty so I contacted the dealership that I bought the truck from and they had me tow it there using gm roadside. So my first hats off to gm, the lady I had on the phone from roadside assistance asked her manager to waive the tow fee as I was having it towed to my home dealership that was > than the 50 miles that they cover for free. Once the truck made it to the dealership, it only took the. A couple of hours to figure out I had a failed lifter and broken rod for cylinder #4. Now I was freaking out because I’ve read horror stories on this site about having to argue with regional managers for warranty work this significant and I’ve heard dealerships arbitrarily saying work isn’t covered under warranty for whatever reason. Thankfully I can say my service advisor set me up with a rental the same day and reassured me that everything would be covered by gm. He did say parts were on backorder and it would take approx 2 weeks. Almost 2 weeks to the day, truck was ready to be picked up with 0 hassle the entire time. This is my 3rd truck with the 5.3 and the only time I’ve had a significant mechanical issue. The truck only had 85000 km (around 50k miles) sure I was PO’d that my truck was out of commission for 2 weeks but I was extremely thankful that gm stood behind their product and was able to fix the truck for me. The truck seems to run fine now but I don’t know if I will keep it as I don’t know if it will be the same or if the issue will reoccur. I do know that my next truck will definite be another Chevy or Sierra. I can’t wait to see the reveal of the new Chevy this weekend at Detroit! Jut thought I would post a positive warranty repair story and throw a kudos out to gm for making things right with me
  10. Hey everyone, I have a 2014 Sierra with the 5.3L, I really don't like posting on the forums for issues because it can give a bad representation of what is generally a good vehicle. My truck never really exhibited any of the usual issues like the vibration but it has had a couple small fixes here and there. Moving seat, rusting frame, etc. this time I just wanted to give everyone the heads up. Well a couple months ago I was driving and the oil pump failed. It took 2 weeks to fix. When it happened I was pretty concerned about any possible damage it caused but the dealer said it looked ok. Fast forward to last week. Merging onto the highway, heard a pop and lights came on everywhere. Got it to the dealer, lifters collapsed on a cylinder. I was without my truck all last week as they fixed that issue. This sunday, less than 60 miles after I picked it up, I went to accelerate in town and heard the same pop but this time it wouldn't even move if I gave it throttle. Towed it down to the dealer and they finally looked at it yesterday. This time they are ordering me a brand new engine. Thankfully I still have powertrain warranty but this is a major disappointment and honestly I don't even trust the truck anymore. What would your recommendations be? Sell it, trade it, keep it and run it into the ground?
  11. Hey Guys, I have a 2010 Chevrolet Tahoe PPV with a 5.3L LMG and a 6L80 Trans (MYC) looking to drop in a 6.2L L9H. As far as I understand it is a direct swap. Would I run in to any issues or codes as far as the L9H not having AFM/DOD? I plan on using the 5.3L PCM and having it re flashed to work with the 6.2 Or do I look for a L94 that has FlexFuel, VVT, AFM like the LMG does?
  12. Hello Ordered a RANGE AFM Disabler today after reading through this forum and others. I don't drive many miles per year - my '14 has a little over 23,000 miles on her - purchased August '14. Truck goes in and out of V4 a lot. Just can't see it helping much with the hills around here and my short trips.
  13. My 2012 Silver is one of the unfortunates to be cursed with AFM. It has 136k on it. It has gone through a quart of oil about every two weeks since I got it at 75k miles, plugs on 1, 4, 6 and 7 have to be changed about every 6 months (photos of #7 that got changed a few days ago because as usual, CLEARLY it was fouled and misfiring) and it DRINKS fuel. My average MPG's hovers around 10-11mpg..not to mention the horrible jolt it makes after cycling between 4 and 8 cylinders. Is there nothing I can do to, if nothing else, reduce the oil consumption?
  14. Hello, I looked 2008 GMC Sierra 1500 that I was interested in purchasing with the 5.3L V8 has 174,000 miles. Truck runs rough at idle, rpms are fluctuating. Check engine light is on with codes P0300 and P0301. Can’t troubleshoot the problem. Coils, spark plugs, spark plug wires, new O2 sensors, new catalytic converters. Guy says that rockers all move so it isn’t Active Fuel Management lifters and he says 150 psi of compression across all 8 cylinders. Truck was at dealership, dealership says problem with cylinder numbers 1 and 8 the P0301 explains problem with cylinder 1 but why isn’t code P0308 being thrown? What else could be the problem?
  15. Does a Range AFM disabler work on a 2017 model? Their website indicates it goes up to 2016. I can't see what should be different... but I think they are overpriced to begin with, so I don't want to shell out the dollars for it if it's a paperweight. My truck is a 2017 1500 with a 5.3L & 6 speed. I only want it so that custom exhaust won't sound stupid. Had an i2 programmer for my 16 and it won't work on my 17... so I quit with the programmer, I'll stick with plug and play if it is truly that.
  16. My 2008 5.3L 4WD Avalanche with ~135K miles has recently been throwing a P0306 cylinder 6 misfire, along with a Stablitrak warning. It first happened a couple weeks ago but only lasted a day. I cleared the code and it was fine for another couple of weeks before it happened again today. It does go through a lot of oil (probably a at every 1,000 miles), and there is a clicking sound. I know from researching this the last couple weeks that its likely failure of the #6 cylinder lifter and/or plug fouling due to the AFM system design and/or old PCV cover. I intend on doing some diagnostics this weekend including inspecting and replacing (if needed) plugs/wires/coils, doing compression tests, and pulling off valve covers to look for stuck lifters/valves. My questions are: 1) Other than the obvious, is there anything else I should be specifically looking out for when running these tests? 2) Are there are any other diagnostic tests I should be doing while I am in there. 3) Assuming compression test is fine, and replacing plugs/wires stops the misfires, can I hold off on replacing a bad lifter if there is one? 4) I would plan on getting a Range tuner to disable AFM (which I should have done when I bought the truck 3 years ago) and replacing the valve coverwith the new one. If the compression test is OK suggesting there is (currently) no ring, gasket, valve, etc. damage, would these measures stave off more issues? 4) If a lifter is bad and I really need to replace it now, can I just replace the one, or do I need to replace them all? Also, how difficult is it to take the passenger side head off to access the #6 lifters? 5) If it does fail compression, am I likely screwed and looking at a rebuild or replacement? 6) Any other advice, recommendations, or thoughts? Thanks in advance!
  17. Hi everyone- brand new to the forum. Thought I'd throw out a question about my 2008 Chevy Suburban LTZ sitting in the shop right now waiting on a replacement GM-cert refurb engine. Should be put in in the next several days. Truck has 165K miles. Started chewing oil back in 2012 at around 80K. Was in shop 3 times in 2013 with the usual AFM issues up until the 110K mile mark when the 3rd operation was done (I think it was replacement of all pistons). All-told, about $7250 of warranty work done to truck related to AFM. Soooooo, truck recently had misfiring on cylinder 5, low oil pressure warning, drop of pressure, left on side of road. Towed to dealership. Engine not holding pressure, needs new engine. I expect the engine to have 3 yrs/100K warranty. My question is this: Should I disable the AFM with the "Range AFM Disabler" (http://www.rangetechnology.com/products/range-v8) device on this 'new' engine to (likely) eliminate any potential issues, or should I trust the newer version of this engine that was ordered will behave and perform as desired. I am also a bit confused about posts discussing 'deleting' the AFM with "kits" or having to put different parts into the engine to turn AFM off, while getting normal, expected behavior from the engine. Thank you all for any feedback. Love this forum! John
  18. A few months ago I bought a 2007 GMC Sierra (new body) with 150,000 miles on the clock. It has the LH6 in it. It has since gotten cold outside and when I start it in the mornings It has what I am sure is a rod knock. It goes away after the engine warms up. It has good oil pressure. I have always been a ford guy and wasn't too familiar with these engines otherwise I would have avoided these early AFM engines like the plague. It sounds a lot "deeper" than a lifter click. I have removed the valve covers and confirmed that I don't have a collapsed lifter or flattened cam. The thing consumed over a quart of oil in the last 2,000 miles. I had a cylinder 1 misfire and when I pulled the plug it was pitted and the porcelain was cracked showing tons of detonation. I replaced the plug and that fixed the misfire. All the other plugs look great. Onto my question. With all these issues an the reputation of these AFM lifters and oil consumption I kinda want to get ahead of it and plan on putting an engine in it. This is my daily driver so i need to minimize down time. I was looking to get a block and get it ready to go in the truck (as money permits) so there is no huge rush or surprises. The problem is these specific LH6 Aluminum blocks were only used from 2005-2009 and are not the easiest/cheapest to find. The LY5 however is the iron counterpart to it and cheap and easy to find since they produced them 2007-2014 and were more common. I don't care about the 100lbs. Does everything bolt up? And would the computer freak out? I plan on eliminating the AFM and putting some trustworthy lifters and a cam in it so I will need some computer work done anyways hopefully it can be programmed enough to handle a different block? Would someone with HP Tuners be able to do the computer work or does the whole thing need to be sent off/replaced?. I've rebuilt a few engines It's just this computer stuff that gets kinda hayzey. If I am deleting the AMF is there another Gen IV block that would work for this application? Screw it and get a 6.0 and stroke it?
  19. I have a 2016 Crew Cab Silverado 4x4 that I bought new last summer. I have noticed that recently when the active fuel management switches from 4 to 8 cylinders that there is a loud (loud enough to hear it with the windows up, A/C and radio on) squeak like noise that comes from the truck. It makes this noise every time it switches from 4 to 8, no matter what the speed. I don't remember it doing this until recently. I've googled active fuel management noise, active fuel management squeak and tons on other combinations, but haven't gotten any results. I wanted to check on here and see what you guys thought before looking like a dumb ass and taking it back to the dealership.
  20. I have a 2007 Tahoe 5.3L LMG (AFM) 4x4 LTZ. Truck has 190k on it. The other day it developed a very rough idle and flashing CEL. Prior to this there was no indication of a problem. Scanner says misfire cylinder 1. I do all of my testing that I can do such as spark plugs, wires, verify injector signal with noid light etc. End up using compression tester to find 0 PSI on #1 and other cylinders at 110-120 PSI. During one of the compression test on #1 the gauge jumped to 60 PSI then next cycle dropped to 0 (unsure how to interpret that). Took truck to local shop and despite my efforts to inform them of the AFM lifter issues that could be causing this loss of compression they basically said that based on the 190k mileage i should only consider replacing with long block rather than repair the heads. They then quote $6600 for Jasper reman and install. So to my question... Are they right the I should do a reman long block or consider repairing heads? I know I have been lucky to get that kind of mileage without issue but just wondering what others would do. Truck is in great condition otherwise and I plan to keep for the foreseeable future. Thanks for your help.
  21. For the LTZ 5.3 vs 6.2...looking at the 4dr 6.5bed...the mpg it shows on the window seems a little low for using AFM...what are your actual numbers you get? We'll say without towing, and with if ya got it...say you just bought it and went on the freeway for a few hundred miles and AFM was on, theres no way to get 18-20mpg, is there?
  22. Hey Guys, I have had my 2015 Sierra for a year and a half now and I cannot stand how the truck shifts through the gears. I have been researching the forums for different fixes or something to help make the truck drive smoother. Long story short, I find that the Range AFM v4 disabler is the best solution available that avoids voiding my warranty. I do not use my truck as my primary vehicle and only put about 7,000 miles on it a year, so I do not want to void my warranty far before it expires considering all the quirks, Direct injection, and other things the warranty could save me $thousands if something breaks. I find that the truck drives around town much smoother without it going in and out of v4/v8 modes and the trans does a much better job managing city driving. So what is the major downfall of the Range AFM Disabler? It drains the battery, especially for someone like me who only drives on weekends. Between Christmas and New Years I had the time to figure something out. In our truck one of the pins in our OBD2 connector provide a constant 12v, which the RangeAFM uses for power. I came up with a relay design that only provides power to this obd2 pin only when the ignition is on, theoretically preventing the RangeAFM from draining my battery when the truck sits. ***Please beware this is a mod I decided to do to my truck and so far I have not had an issues. Modifying your own truck is your responsibility, not mine.*** Some Key points about the mod: 1. Provides the same power source as always, but only allows the OBD2 pin to access the power source when ignition is on. 2. I have an optional switch that will provide the original constant power to that pin in the OBD2 plug. The reason I did this is because I have dealer oil changes and I want everything to operate as the truck is designed to when they connect to my OBD2 port. The switch bypasses the relay control, therefore allowing factory operation. Before my dealer visits, I removed the RangeAFM, and flip the switch. You can place your switch anywhere, mine is hidden. 3. When cutting the wire from pin 16, I soldered and heat shrink my connections, and wrap it back up with the same fabric tape GM uses. The reliability of this mod depends on your ability and skills. 4. Not that this is a big deal, but when I get my GMC email/report every month it does not show there are issues since the RangeAFM is off while the truck is sitting. Thanks again to everyone on the forms for your input that led me to this decision. When my warranty is up I cannot wait to program/tune the truck, but for now I am happy with these results.
  23. AFM-Mods

    Hello, I had a couple of questions. First When i go to autozone.com and enter my vehicle there is two options for the 5.3 (7) or (0) What are the differences between the two? I have the (7) in my vin but I'm still not really sure what the differences are between the two engine codes. If there actually is a difference in performance or internal parts? Next, What are everyone's thoughts on disabling AFM my thought is its robbing me of some horse power and throttle response. I know i can get a tune to disable it but i wasn't sure about the pros and cons of that. I have heard after a while the engine will start eating oil because of AFM. I only have 84000 but still. I was also looking at getting a CAI between K&N and Volant I was leaning more towards Volant because of the closed intake box not sure if it has that much of difference but, i live in az and its dusty and when it gets muddy i don't want engine to be sucking up that water with the intake. I know the intake is not going to give me substantial amount of Hp or torque. The engine seems to breath better i have a friend with same truck and has K&N and it sounds really healthy and throaty. Pros cons on each? I have flowmaster super44 and love it I think that if i had an intake it would just sound even better. With that i was wondering for as cheap as it is with throttle body spacer if any one has really noticed a difference. Lastly seems like Diablotune is the way to go any other tuners that maybe a little cheaper that does all the same stuff? Thank you in advance Jordan
  24. I have read every muffler swap, delete, topic, post, on this forum and have not found anything of anyone using a smaller case muffler (magna flow) and leaving the resonator and flapper in. Has any one done it or tried it before they cut out one or the other? Im currently looking at running Magnaflow 12259 18" with resonator and flapper or Magnaflow 12589 22" and resonator delete and keeping flapper in. Would either of those setups achieve this: NO drone/chopper I dont want it too loud quiet on cruise nice low key rumble on start, idle, and getting after it
  25. Ok, so I know that there is and has been an ongoing issue with the AFM lifters sticking or collapsing entirely. I have a 2007 GMC Sierra 5.3 Flex Fuel 4X4 - 165k miles. Pretty regular maintenance, I am not OCD, but I try to do my best at around 3500 miles - full synthetic Mobil 1 oil, AC Delco Filter. Here is my situation.... No ticking whatsoever (which I know is usually attributed to this), BUT terribly bad misfire on Cyl 4 (on the the AFM cylinders, I know) and throwing the typical 304 code with stabilitrak warning. Before pulling the valve covers, I checked EVERYTHING (well, except compression) - I checked plugs, coils, injectors, fuel and oil pressure, etc. That is what led me to go ahead and pull the valve covers to check for any slack in the rockers/valves (even though there is no noticeable tick. Initially pulling the covers, I was pleased with how clean everything was....and how tight everything was. No slack in the rockers whatsoever, from what I could tell the valve springs look good, etc!! Yay...but WTF is causing this? Well, I fired up the truck and found that the intake valve in cyl 4 was not moving. BUT...when my wife got home, I had her turn the engine over for me so I could see it all without doing it myself. Here is what I am confused about - on start up, the valve moves...but only one time! It goes through the whole compression cycle then stops once the engine is running. If it was collapsed, it wouldn't push the valve on start up, would it? Could this be the VLOM and not the lifter? Thoughts? Thanks from the new guy here!
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