cygnusx1 Posted September 28, 2009 Share Posted September 28, 2009 Yup, what would cause that? Recent work done, fuel tank removed and welded, new BPR8ES plugs gapped to 0.025". It had the miss with the old plugs too which is why I changed them. Backflushed the injectors to rule out a plugged injector. Added gas-dry and injector cleaner to the tank. EDIS seems to be in excellent working order. The miss is only heard/felt at idle and not isolated to one cylinder. Confirmed by pulling plug wires. Driveability is great and strong. If I set the AFR's so that my LC1 wideband reads 13 the engine has a terrible misfire. In order to stop the misfire and get a smooth idle, I need to get into the 10.5 AFR range. Last week, and forever before that, the car liked 13 AFR at idle. Any ideas what is going on? Is my O2 sensor giving me the truth? . Here is the initial thread in which I investigated the EDIS system: http://forums.hybridz.org/showthread.php?t=154117 Quote Link to comment Share on other sites More sharing options...
softopz Posted September 28, 2009 Share Posted September 28, 2009 did you eventually do a compression check? Quote Link to comment Share on other sites More sharing options...
ktm Posted September 28, 2009 Share Posted September 28, 2009 1) Have you recently calibrated you wideband? Innovate recommends 3000 miles or 3 months. 2) What are you using to read the afrs? A gauge or MS? My Innovate G3 gauge is fubared. It reads up to 4 points off the LC-1 wideband as recorded by Logworks and my ems. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 28, 2009 Author Share Posted September 28, 2009 Yeah I run the LC1 reading through MSII through the Megaview display.. I calibrate every two months or so. I will recal tomorrow morning. I need to do a compression check ASAP. Have to get the tool. Quote Link to comment Share on other sites More sharing options...
jc052685 Posted September 28, 2009 Share Posted September 28, 2009 check coolant temp sensor.... Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 29, 2009 Author Share Posted September 29, 2009 Maybe I have a tank of bad gas!! That would explain everything. I filled up at a station I never use, and one that probably does not move a lot of the 93 Octane grade either. It's probably old gas. I still have a full tank....drain it or drive it? Could bad gas require that decrease in the AFR's to run more properly? Quote Link to comment Share on other sites More sharing options...
stony Posted September 29, 2009 Share Posted September 29, 2009 bad wide band sensor??? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 29, 2009 Author Share Posted September 29, 2009 While I initially thought the WBO2 was going loony also, I loaded an old map, and it gave me the same idle AFR's I was getting a year ago. 12.8. Which used to idle great in this engine. Not anymore. Since the gas tank swap I am needing 10:1 (bumping up the Ve values at idle) to idle nearly decent. This is the first tank of gas since the tank was repaired. Quote Link to comment Share on other sites More sharing options...
g9m3c Posted September 29, 2009 Share Posted September 29, 2009 Could bad gas require that decrease in the AFR's to run more properly? This post is based on mostly common sense and possibly faulty logic. Be warned. If you got bad gas, then obviously, it wouldn't combust as well. That would mean the engine would need more of it, thereby decreasing your AFR. Make sense or no? Quote Link to comment Share on other sites More sharing options...
softopz Posted September 29, 2009 Share Posted September 29, 2009 could be bad gas or bad wideband or bad compression you havent narrowed to which one though keep us posted. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 29, 2009 Author Share Posted September 29, 2009 Thanks for the ideas and backing on my thoughts. I don't think I suffered a loss of compression overnight. So I am going to drain off some fuel from the bottom of the tank so see what it looks like. I was reading that if the gas was purchased from a cheap source, it could be less refined than it should be, and may feel a bit oily. In fact when I took of my injectors, I thought the fuel felt a bit oily. I didn't wonder about it too much because I had added a bottle of dry-gas and a bottle of injector cleaner. So I can't say for sure that the fuel was oily, or that the additives made it so. Whatever the case may be. The engine wants A LOT more of it to idle right. I doubt the wideband went bad because loading an old map yielded the expected AFR's. Today, I will try to use up a tank of gas.....or transfer some of it to containers. I should make the gas station pay for my time lost here!! Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 13, 2009 Author Share Posted October 13, 2009 I am on the second tank of fuel, manually backflushed the injectors with compressesd injector cleaner in a compressor hose, the car still needs 10:1 to idle smoothly. It runs fine at all other points on the VE table, with the O2 sensor reading exactly where it did before, matching my AFR table. For some reason, the fuel must not be burning well at idle. Either the injectors, are not atomizing properly, or something else has effected the combustion process ONLY at idle. At full song, 15psi boost, 5000rpm's, I am making my AFR's as called out in the AFR table 12.5:1. I cruise around 14.7 fine. Idle is a smooth but stinky, 10:1. If I back out any idle fuel, the car idles and lopes with tons of misfires. Mystery. Yes, I know....check compression. Would that effect only idle and all cylinders evenly? The problem started after a fuel tank flush and reinstall by a radiator shop. I am tempted to send out the injectors for a cleaning and blueprint. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 14, 2009 Share Posted October 14, 2009 Maybe your gas station switched to a winter blend, I'm not sure if that would make such a difference though. Quote Link to comment Share on other sites More sharing options...
niner11 Posted October 15, 2009 Share Posted October 15, 2009 Dave have you played around with your injector settings just to see if it makes any difference? opening times? Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted October 16, 2009 Share Posted October 16, 2009 Verified timing with a timing light? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 16, 2009 Author Share Posted October 16, 2009 Yes I checked the timing with my light. It hasn't changed. Niner good idea, I'll try messing with that to see if it does anything. Would poor atomization require more fuel for a smoother idle? Quote Link to comment Share on other sites More sharing options...
Zmanco Posted October 16, 2009 Share Posted October 16, 2009 This is a long shot, but are you running any of the ignition timing filters and/or masks with MS? I had experimented with a timing mask and forgot about it and then one day couldn't get a good idle. It felt like a misfire/no spark, but was inconsistent across the cylinders. I think the mask had been set a little too long to be safe for idle, and for some reason all of a sudden it began to cause issues. What if you set the idle higher, say around 1000 - 1100 rpm? What AFR is required for a good idle then? If that solves it, I'm thinking ignition, not fuel delivery. I can't help but wonder if the tank work is a red herring distracting you from an ignition issue. Sorry I can't offer anything more than that. But I'm following this because I seem to come across the same issues as you, usually a year or so later. Thanks for forging the way! Quote Link to comment Share on other sites More sharing options...
ZR8ED Posted October 16, 2009 Share Posted October 16, 2009 Why were you idling at 13's before? May this be a long term issue getting worse? You should have no issues idling into the 15's even down in the 5-600 rpm's. Misfire? ignition? Idling into the 10's beware of dumping too much fuel into the exhaust and causing a fire. (don't ask how I know this can happen) Scott. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 16, 2009 Author Share Posted October 16, 2009 Great points and I appreciate all the tips!! I am going to "fine tooth comb" this issue once the driving season is over. I had tried older maps which were labeled as "runs great" and still had the problem so I don't think it's an .msq setting. I think it's some physical change that happened over night, so to speak. Ever since I have had MSII I have had to idle in the mid 13's AFR to get smooth, non-popping, idle. I think it's fairly common for the low compression turbo motors to idle that rich. Needing 10:1 all of a sudden, on the other hand, is absurd. How can I pinpoint an ignition problem? When I pull each plug wire to observe the sparks, they don't miss a beat. The miss is felt in the motor, but heard in the exhaust as a "puff". Is there a way to tell if the plug misses a spark? Datalogs do not show any missing. I hear/feel the miss no matter which sparkplug wire I leave off. Telling me that it is propogating in all the cylinders at random. Side story: I had a problem in my 90 Honda once, where the motor started misfiring, and then it wouldn't run anymore. The computer was throwing no codes, and there was NO spark at all at the plug wires or plugs! Took me a full day to figure it out. I even changed the ignitor and checked all the components to the specs. Turns out that the sparks had burned a tiny hole through the nose of the coil and the spark was jumping from the coil directly to the negative coil post! So the ECU thought everything was fine because the spark was going out. It had no idea that it wasn't getting to the plugs. I found it when the sun was setting, and I saw the spark jump to the post. Quote Link to comment Share on other sites More sharing options...
softopz Posted October 18, 2009 Share Posted October 18, 2009 Thanks for the ideas and backing on my thoughts. I don't think I suffered a loss of compression overnight. Ya actually you can loose compression overnight, detonation can be very quite sometimes. -Did you put your old plugs back and see what happened? you had said that was some of your recent changes. that would be the first thing I would do. -Like I said before it could also be a bad wideband going looney (you havent verified that you just put old maps back on) Find a buddy with a wideband and do a quick swaparoo most of them used the bosch lsu 4.2 sensor. This would be the second easiest thing you can do. -You also said you had done some gas tank work I dont know how extreme the changes were, But I would try a quick volume/flow test. Get a jug put it on your feed after pump and time how fast its filling up. There is some more info on zcar about this basically to see if your pump is pumping adequatly (fuel pressure gauge wont tell you this) -one more thing Dave just borrow a compression tester you still havent shut me up Iam not going to stop ....since you eliminated all your previous possiblities gas tests and map/msq errors. I bought from princess auto aka harbour freight here in Canada it was 20 bucks and its a easy/fast test to do. Just remember pull your plugs out and have throttle open while cranking (4 - 6 cranks is good a remote starter helps too if you dont have someone to crank car for you ) write the numbers, then squirt a little oil in each cylinder this a wet test. If you start seeing numbers increase than you got bad rings or bad headgasket. been using it for 2 years no problems very handy tool. I just did a test before removing my head gasket all were good except number 4 ofcourse there was a huge tell tale sign of water steam in exhaust but it was good see where I was loosing power and sure enough gasket near 4 bent. How can I pinpoint an ignition problem? I would put a timing light on each wire and see how it flashes that will definatly tell you allot I know I have intermittent miss at 3 random cylinders. edit now that Iam thinking more of your issue I have the same symptoms I did have a miss and could have been why I blew a headgasket. Especially after you had said you removed plugs and tried to notice if the miss leaves. How are your injectors wired? I ask because when reading about wasted spark setups it seems that the spark goes to the plug with the most compression (valves closed) and basically atomization of fuel and air. I put a timing light on each wire and I also found an ignition miss. This to me can only be caused by atomization theory or triggor wheel/pick up. What I will do ( put the light again note cylinders and check how injectors are wired to that cylinder and switch driver their using off db39. I will also try different injection options in megatune dont you just love elimination troubleshooting BUT I have to finish my headgasket in the meantime maybe you can beat me to it. Quote Link to comment Share on other sites More sharing options...
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