ssbtech Posted June 8, 2012 Author Share Posted June 8, 2012 Would a bad ignition coil cause roughness? And could that in turn lead to a condition which the ECU responds to with that extreme knock correction? If so, I could move the coil to another cylinder and see if the roughness follows it, then replace the coil... Link to comment Share on other sites More sharing options...
bmx045 Posted June 8, 2012 Share Posted June 8, 2012 you could move the coil and see if the roughness follows. i don't *think* a misfire can falsely trigger the knock sensor. what i do think can happen is a cylinder running so lean that it fires at times with a lean mixture and knocks, and other times misfires from so little fuel in the mixture. if at idle, it misfires, but while driving is fine(meaning no misfire) it could be clogged injector. my friend had this issue where it would only miss at idle, but a clogged injector can flow enough fuel to not misfire but not enough fuel to appropriately achieve a rich enough afr to not knock. meaning the flow is reduced in the full spectrum- at idle and while driving, but while driving not misfiring, instead running lean because of the flow restriction. i suppose you could have knock if that happened. Link to comment Share on other sites More sharing options...
ssbtech Posted June 8, 2012 Author Share Posted June 8, 2012 Ok, I'll do a "around town" log with the roughness monitor to see if the roughness drops when driving. Thanks Link to comment Share on other sites More sharing options...
ssbtech Posted June 9, 2012 Author Share Posted June 9, 2012 Update: I've left it at the dealer where they didn't see anything wrong with their laptop plugged in, but swapped the #2 and #4 injector. It ran really rough after that so he swapped them back, but noticed a nick in the injector's O-ring. New injector on order and I have a new Forester to drive around in for the weekend. He said when he put it back there was a strong sulphur smell, so perhaps that nick has been there for a while causing the odor. Link to comment Share on other sites More sharing options...
iNVAR Posted June 9, 2012 Share Posted June 9, 2012 *crosses fingers* keep us posted Link to comment Share on other sites More sharing options...
ssbtech Posted June 12, 2012 Author Share Posted June 12, 2012 They should have the other injector this morning, so hopefully it'll be better this afternoon I wonder why his laptop wasn't showing any problems. Then again, when I showed him the roughness monitor log for Cyl2 and the FBKC at -7 he didn't seem to think that was a problem Link to comment Share on other sites More sharing options...
ssbtech Posted June 14, 2012 Author Share Posted June 14, 2012 Update: New fuel squirter is in #2, here's an LV after they reset the ECM and took it for a drive. I've driven it about 50km (mixed highway, city) since the work was done. Also watched the roughness monitor while idling for a few minutes. Previously it hit a count of 23 on Cyl2, now it just shows the normal occasional one or two here and there. So far I think this has got it. Still have to do a 3rd gear pull. Romraider question: I'm confused about the cars definition XML file. I see now that I didn't have it during the above logs. Now that I downloaded the latest definition file, things like engine speed and throttle opening aren't registering a reading in RR. Link to comment Share on other sites More sharing options...
ssbtech Posted June 16, 2012 Author Share Posted June 16, 2012 Ok, best I could do today. Log and LV attached. Impressions are that the car is running better, but I still get some sulphur smell on the full WOT pull. Wasn't as bad as before however. Two LVs: one pre-pull and one after. I enabled the roughness monitor because I wanted to see any misfires. The injector took care of those. Post pull LV on the left, pre on the right.Log.csv Link to comment Share on other sites More sharing options...
ssbtech Posted June 16, 2012 Author Share Posted June 16, 2012 Update: Reinstalled intake air resonator and removed the engine upper cover as there were a couple of loose popit screws and it was rattling around a bit. Tightened bolts that were about to fall out of the power steering fluid reservoir (dealer must have loosened it to make getting to the air filter easier). Re-logged. Only able to get a short 100% pull then 5th gear cruise for a whort while. Damn minivan and traffic laws Two LVs (one first pre-log, second post-log) and log attached. I was happy to see that the FBKC has decreased quite a bit. Still a very strong suplhur smell building up late in the 100% throttle pull then tapering off for several seconds after.romraiderlog_20120616_143128.csv Link to comment Share on other sites More sharing options...
bmx045 Posted June 16, 2012 Share Posted June 16, 2012 lot of fbkc, trims look okay, slightly lean in closed loop and rich on boost. boost leak test? suspension parts loose? clunks? rattles? heatshield? Link to comment Share on other sites More sharing options...
ssbtech Posted June 17, 2012 Author Share Posted June 17, 2012 Ok, I'm lost. I thought the red numbers meant leaning out. I have a suspension clunk over speed bumps at low speed, doesn't make noise on a smooth highway. Don't hear/see anything loose. Nothing that I can access anyway. Throttle response seems a bit better after the new injector. It's almost as if the car has lost a hundred pounds. Link to comment Share on other sites More sharing options...
bmx045 Posted June 17, 2012 Share Posted June 17, 2012 Negative trims indicate the ecu has learned to pull xx percent of fuel to achieve the target afrs. Link to comment Share on other sites More sharing options...
ssbtech Posted June 17, 2012 Author Share Posted June 17, 2012 Okay, so running rich means that the ECU is cutting fuel because not enough air is getting to the engine. I'm assuming that the o2 sensor is showing less oxygen than expected based on the reading from the MAF sensor? Correct? I've also noticed since the injector went in a slightly surging, almost like a slipping clutch, in 5th gear under acceleration. A slight bit in 4th gear too. The latest log should show this shortly after the 100% pull. I'm wondering if any damage has been done from the bad injector. Perhaps a compression test is in order? Not seeing anything goes in the way of oil consumption Link to comment Share on other sites More sharing options...
bmx045 Posted June 18, 2012 Share Posted June 18, 2012 no, the ecu is pulling fuel because the afr detected is lower than target. this could mean a few things. either your injector latencies are too low, or your maf scaling is too high. or, you have an exhaust leak that is causing the turbo to spin not fast enough, thus causing more vaccum between the turbo and throttle body than expected (less air into engine). the turbo should be spinning X revolutions per minute to feed the engine with enough air, and idealy there should be close to 0inHg between the turbo outlet and the throttle plate, if there's less than that then the engine will suffocate. therefore, there is too much fuel for the mixture thus the richer afr thus the ecu pulling fuel. that's for more extreme scenarios, your trims, CURRENTLY, in those lv's are acceptable. you want all trims to be no greater than +/- 5%. and the D range as little as possible. Link to comment Share on other sites More sharing options...
ssbtech Posted June 18, 2012 Author Share Posted June 18, 2012 After some driving today the A column shor back up to 6.1 again today. As for the FBKC, is there any documentation that shows an acceptable range for correction? I showed the dealer mechanic and he said "that looks fine to me". Guess I should trade the car in Link to comment Share on other sites More sharing options...
bmx045 Posted June 18, 2012 Share Posted June 18, 2012 one -1.41 here or there is the norm, preferrably anywhere but the right-farthest column Link to comment Share on other sites More sharing options...
iNVAR Posted June 18, 2012 Share Posted June 18, 2012 The LV looks good, but the FBKC of 4 degrees under WOT is not good. Link to comment Share on other sites More sharing options...
ssbtech Posted June 18, 2012 Author Share Posted June 18, 2012 I guess a compression test is in order then? Link to comment Share on other sites More sharing options...
bmx045 Posted June 18, 2012 Share Posted June 18, 2012 never a bad idea, IMO Link to comment Share on other sites More sharing options...
bmx045 Posted June 18, 2012 Share Posted June 18, 2012 did you do the plugs yet? boost leak test? Link to comment Share on other sites More sharing options...
ssbtech Posted June 18, 2012 Author Share Posted June 18, 2012 Spark plugs were done at 96,000km I think (whenever the schedule called for them) so they're not due for a while yet. How do I do a boost leak test? The logs show that it seems to be holding OK, no? Link to comment Share on other sites More sharing options...
ssbtech Posted June 18, 2012 Author Share Posted June 18, 2012 Metallic sounding heat shield rattle in third gear at 40kph on light acceleration. That could account for the knock correction early in the pull, but the continued correction after that... Sulphur smell is just as strong. I'm due for an oil change in 1,000km so I'll likely have them do the compression test then. No oil loss over the last 5,000km, oil is still golden on the napkin. I've ordered a Blackstone test kit, should take a few months to get across the border Link to comment Share on other sites More sharing options...
bmx045 Posted June 18, 2012 Share Posted June 18, 2012 Well solve the heatshield rattle first and foremost. Re-evaluate once eliminated as a culprit Link to comment Share on other sites More sharing options...
ssbtech Posted June 19, 2012 Author Share Posted June 19, 2012 I see my LV keeps getting better and better. I tried logging at the speed and RPM I get the heat shield rattle at and when I got home my laptop hadn't recorded any numbers, just the column headings Link to comment Share on other sites More sharing options...
ssbtech Posted June 20, 2012 Author Share Posted June 20, 2012 Pardon my ignorance, but what exactly is knock correction? I know it's changing the timing, but the timing of what? Valve timing? Link to comment Share on other sites More sharing options...
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