ShoBoat Posted April 5, 2015 Report Share Posted April 5, 2015 So i have put my girl back in her summer mode once again, a little early this year. Installed my H&R's, summer wheels, tune, intake and 3 bar. Mine has the V8 LMS tune. I started seeing some KR at lower RPM's at 60 to 70 mph at mid throttle. Then I started to replicate the issue while logging with Forscan and my laptop. AT mid throttle (without downshifting) (once boost got above 4 PSI) I was seeing KR of 4.5? I decided to try some WOT runs, no KR to speak of but I am getting a hesitation (shudder) at the top end to 2nd and 3rd. I checked all the usual suspects, oil in the CAC nope. Plugs, changed them and gapped to 30. Air cleaner check. Fuel was the last on my list as we still have winter gas in the pumps, changed stations and filled up with 94. No change. Called LMS and they said its probably the fuel. SO in goes some 110 Octane fuel. That should fix it? Nope.... So I then tried to load the 91 V8 tune. Same issues. Frustrated I went to the stock tune and the issues go away. I changed the map sensor only and returned it to stock. All other mods stayed on the car. I even swapped out the map sensor to rule that out. No luck. It was running strong at the end of last year with no problems with the tune and all the mods. I did put the winter package on a little early so it was still above freezing when I did. Any thoughts? Has anyone experienced similar issues? EkbergJen and RudyFloum 2 Quote Link to comment Share on other sites More sharing options...
mjhpadi Posted April 5, 2015 Report Share Posted April 5, 2015 Yes, other members have seen this issue. Hopefully you are not using Sunoco fuel. We have discovered it is one of the lest favorable fuels to run. People have experienced high KR and I personally, after many years and vehicles, have discovered it will deliver the lowest gas mileage of any of the quality fuels available. Honestly, it yields lower mileage than some of the discount fuels out there, both in regular and premium grades. Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted April 5, 2015 Author Report Share Posted April 5, 2015 Yes, other members have seen this issue. Hopefully you are not using Sunoco fuel. We have discovered it is one of the lest favorable fuels to run. People have experienced high KR and I personally, after many years and vehicles, have discovered it will deliver the lowest gas mileage of any of the quality fuels available. Honestly, it yields lower mileage than some of the discount fuels out there, both in regular and premium grades. I have tried Esso and Petro Canada, they are the only 2 that offer 93 and 94 octane respectively. Both same results in terms of the KR at least. I am almost certain at this point that it is cold weather related and not fuel. As I did put in some 110 race gas and still had the same issue. More to come. Quote Link to comment Share on other sites More sharing options...
mjhpadi Posted April 5, 2015 Report Share Posted April 5, 2015 Sorry, I can't remember how he cured it, but I will do some research and see if he can give you some suggestions, give me a few hours. Quote Link to comment Share on other sites More sharing options...
mjhpadi Posted April 5, 2015 Report Share Posted April 5, 2015 Just sent a PM asking him to stop by and discuss what he has found...if I remember correctly, I believe he narrowed it down to a faulty knock sensor, but don't quote me on that, I just think that is what he found.... Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted April 6, 2015 Author Report Share Posted April 6, 2015 Thanks for the assist! Any help would be great. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
larrylu Posted April 6, 2015 Report Share Posted April 6, 2015 Hi ShoBoat I can't say I cured my occasional high KR issue and I also can't even say I really figured it out do don't know how much help I can be. I have wrestled with it for a long time and feel like I've maybe gotten some insights. First I agree cold weather is a major player. Might be an open loop thing but that depends on how long our cars are in open loop. I've heard some say only a very few seconds and I've heard some say a few cold minutes. My A/F seems perfect at all times. Im not sure exactly how but there is a cold connection for sure. My most common occurrences will be usually when the engine is very cold, at very low throttle low load. Another common denominator seems to be low load lugging as in a freeway on ramp merge. I have had some rare instances when the spike will be tied to a brief, random tranny glitch I get that I see on rare occasions, and a KR spike will accompany the glitch. Octane boosting will reduce the size of my spikes but will not make them go away. Changing to a 91 octane tune (I always run 93) will reduce the KR but will not make it go away. I've entertained the possibility that the reading is not spark knock at all but a noise the KR sensor is reacting to as spark knock. Might be tranny since I have seen a connection with my tranny hiccup. Might be a cold engine noise but nothing my ears can confirm. I'm not entirely giving up but for sanity's sake I'm pronouncing it a non harmful unknown phenom as it never occurs at WOT. I have changed my KR gauge to not retaining highest and lowest so now I just see it when it happens. Helps me to not obsess. I have noticed I have not spotted an occurrence for a while so I'm thinking I'm about to go back to running 4X for the summer. Feel free to bounce ideas off me if you feel the urge as I've been wrestling with this mystery for a long time now and I love to read other ideas on the topic! Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted April 6, 2015 Author Report Share Posted April 6, 2015 Thanks for the reply larrylu. On yours have you checked the Knock sensor wires? And the engine bay for items rattling? So after a bit of time messing around in the garage, I am no closer to discovering the culprit. I have looked into the intake and CAC with my snake cam. Found noting really special in the intake, no real additional build up on the valves. And the CAC is bone dry. Cleaned the TB and sensors. I have gone over the logs and compared them to last year the only thing that stands out is the outside temp. Today it's a balmy -1C and like my friends to the South we also had some snow over the weekend. Since I also tossed in 10L of 110 race gas, I'm thinking it's not fuel related.The shudder is registering as misfires (feels like it too) on Forscan and Torque. With the stock tune it's perfectly fine, no shudder and nearly 0 KR at all. At least the list is getting smaller.Spark blowout? (Doesn't explain the KR) Also plugs are at 30. I know that with the V7 LMS tune some were reporting similar issues. Maybe Tune? In combination with the cold? (Could possibly explain both) Update below.Injector(s)? An update to the above, I spoke with Anthony from LMS today. He is reporting no other users are having the hesitation issue. So I am now thinking that the KR and Hesitation might be unrelated. And another user reported his Hesitation was in fact a faulty injector. And could only be duplicated with the tune in it. (I'll have a fun time with that one) I am convinced that the KR is cold weather related, I know that for a fact last year I experienced pretty much 0KR at any load and throttle position. Even on the hottest days. The PCM must change something once the ambient temp drops to a certain mark. We have some warm weather in the forecast coming up. I will be curious to see if effects the KR at all. Quote Link to comment Share on other sites More sharing options...
larrylu Posted April 6, 2015 Report Share Posted April 6, 2015 I have checked off/looked into most if not all of the items you mentioned with also no problems found. I have not had a shudder/misfire component to my KR episodes. That does leave the possibility of open loop period in the cold weather during a warm up, that could access some values in tables not otherwise used. I'm also fine running stock. One interesting thing I've watched is in the middle of an episode, cold car, cold temps, less than 1 minute of driving, with no load, 2000 RPM, second gear, KR of over 5. I tried to back off the throttle, no change. Then blip the throttle ....no change. Then all of a sudden it was gone and back to normal. Like a ghost. This scenario I repeated several times over several days. I haven't seen a bad KR reading in a month! Octane affects it. Tune affects it. Cold affects it but none of these factors can cure it except for return to stock. There is a definite on and off to it so its transitory. I feel like I'm more acquainted with it but still no answers Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted April 7, 2015 Author Report Share Posted April 7, 2015 So a small update, I swapped out the plugs again and no change. I then proceeded to re clean the 2 map sensors and I reset the learned behaviour through Forscan. (Reset trans and other adaptations). Weird it's not as bad as it was. Even KR seems to be lower than before. It's still there but not nearly as severe. More to come. Quote Link to comment Share on other sites More sharing options...
SHOnUup Posted April 9, 2015 Report Share Posted April 9, 2015 Anyone know what the TSB regarding the "fuel delivery module" encompasses? Could that be the issue that may burn out the injectors, or cause the hesitation at higher demand? Just a shot in the dark here. Rich Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted April 9, 2015 Author Report Share Posted April 9, 2015 Another update, I decided to move down to the 2 bar tune. And no difference, I then swapped out the 3 bar sensor for my newer one (from the 3 bar tune) reset the adaptations and it appeared to be gone. I picked up another 3 bar sensor and loaded the 3 bar tune again last night. Unfortunately it's been raining for the last 2 days so I haven't been able to really test it out. Rich, I too would like to know what this TSB is about. I looked at all the TSB's for the 13's and I didn't see that one. Quote Link to comment Share on other sites More sharing options...
SHOnUup Posted April 9, 2015 Report Share Posted April 9, 2015 Rich Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted May 28, 2015 Author Report Share Posted May 28, 2015 So it seems that I have resolved my weird KR issues, and let's just say it wasn't what I expected at all. I know have 0 KR pretty much all the time. Even lugging in a high gear at 55 to 70 mph. I have seen boost levels as high as 9 psi in 6th with no KR in fact it's adding timing same as last year. Now that I have a fix I will post a how to. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
Polskifacet Posted February 6, 2016 Report Share Posted February 6, 2016 I am having the exact issue. What was the fix? Quote Link to comment Share on other sites More sharing options...
SHOdded Posted February 6, 2016 Report Share Posted February 6, 2016 Securing the knock sensor wires in particular, and other wiring in the harness in general. Much play in the KS wiring. Quote Link to comment Share on other sites More sharing options...
ShoBoat Posted February 6, 2016 Author Report Share Posted February 6, 2016 I am having the exact issue. What was the fix?As Stated above, KR sensor wires have been an issue. Winter fuel blends seem to be cause for me of the hesitation. Sent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
ramairetransam Posted March 30, 2017 Report Share Posted March 30, 2017 Thanks for the reply larrylu. On yours have you checked the Knock sensor wires? And the engine bay for items rattling? So after a bit of time messing around in the garage, I am no closer to discovering the culprit. I have looked into the intake and CAC with my snake cam. Found noting really special in the intake, no real additional build up on the valves. And the CAC is bone dry. Cleaned the TB and sensors. I have gone over the logs and compared them to last year the only thing that stands out is the outside temp. Today it's a balmy -1C and like my friends to the South we also had some snow over the weekend. Since I also tossed in 10L of 110 race gas, I'm thinking it's not fuel related. The shudder is registering as misfires (feels like it too) on Forscan and Torque. With the stock tune it's perfectly fine, no shudder and nearly 0 KR at all. At least the list is getting smaller. Spark blowout? (Doesn't explain the KR) Also plugs are at 30. I know that with the V7 LMS tune some were reporting similar issues. Maybe Tune? In combination with the cold? (Could possibly explain both) Update below. Injector(s)? An update to the above, I spoke with Anthony from LMS today. He is reporting no other users are having the hesitation issue. So I am now thinking that the KR and Hesitation might be unrelated. And another user reported his Hesitation was in fact a faulty injector. And could only be duplicated with the tune in it. (I'll have a fun time with that one) I am convinced that the KR is cold weather related, I know that for a fact last year I experienced pretty much 0KR at any load and throttle position. Even on the hottest days. The PCM must change something once the ambient temp drops to a certain mark. We have some warm weather in the forecast coming up. I will be curious to see if effects the KR at all. you can see misfires on torque? I have the app and cant get that to register. Quote Link to comment Share on other sites More sharing options...
Bosscav Posted April 13, 2017 Report Share Posted April 13, 2017 Sorry to resurrect this but can anyone provide an image of the engine bay showing the KR wiring? Might be a good idea for all of us to just tighten it down, regardless of tune or not. SHOdded 1 Quote Link to comment Share on other sites More sharing options...
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