fixinto Posted June 9, 2015 Share Posted June 9, 2015 LOL, Ya i feel ya about diggin the spooky chicks. I will also tell you what i Tell everyone else after they get the intake off and put it back on. Double , Triple, Quadrupedal, check the very small vacuum line in the rear of the intake that goes to the fuel regulator, that little sucker loves to pop off and make life poopie. Also, double check the IACV solenoid plug. A quick and dirty check would be to bump your steering wheel to one side while in park and see if it idles up a bit. Not sure how that would cause a cylinder 2 misfire or even a bank 2 misfire. still leaning toward something going on just with bank 2. wonkey O2 or something, not sure. Another question i am curious about is this, after it lines itself out and starts running normal do the fuel trims come down on bank two? SO strange. IF it wasn't such a pain to track down the nutty stuff, i would dare say it was interesting. "sorry i have a thing about puzzles or something" Not the pieces u put together, more like stuff you have to find with logical deduction mixed with some knowledge of what your doing. I hope you get it lined out. pat Link to comment Share on other sites More sharing options...
JeffsR50 Posted June 9, 2015 Author Share Posted June 9, 2015 (edited) yeah I knew going in that it might require a few cranks of the wrench - and yep the regulator line was a bit loose on the fitting when I removed the intake - but I raced to the shop and got a good 3 feet of nice new vacuum line + replaced most of the lines - ( definitely the ones in back). yep the iacv is working good - bump the wheel or turning on ac bumps up the idle right away. I did just run some injector cleaner - chevron - I was thinking maybe I got some winter mix fuel and that was doing crappy things when the weather turned hot - I put 85 in and havent had the misfire since, but its been a bit cooler out too. - but yep Ill do another check and make sure the new lines back there havent somehow wiggled off. + I am going to put the other disty cap on and see how she does over the next several days. thanks again man fun n games Edited June 9, 2015 by JeffsR50 Link to comment Share on other sites More sharing options...
fixinto Posted June 9, 2015 Share Posted June 9, 2015 Cool man, I am rooting for you. Let me know how it turns out. I am getting ready to Drop the Trans in mine to put a clutch kit in it. Probably throw a new rear main seal in the engine, and front main in the trans while she is down. Fun times indeed. =) Link to comment Share on other sites More sharing options...
fixinto Posted June 11, 2015 Share Posted June 11, 2015 Howdy, I just thought of something else. When i did some work on my R50 the driver side exhaust manifold was cracked in a couple of places but it didn't have a super loud exhaust leak or anything. But if you have a cracked exhaust manifold and it is letting outside air come in before the O2, it has been documented in places that it will cause the O2 sensor to read lean and try to comp for the extra air. /shrug, long shot i know, but who knows, I just figured i would throw it out there in the pile of other things it could be. pat Link to comment Share on other sites More sharing options...
JeffsR50 Posted June 11, 2015 Author Share Posted June 11, 2015 interesting...yep I havent really tried to look for exhaust leaks -maybe Ill do a seafoam treatment this weekend just for that purpose. Link to comment Share on other sites More sharing options...
JeffsR50 Posted June 28, 2015 Author Share Posted June 28, 2015 fuel pressure test today - 40lbs at ignition, 34 while running, leak down test holds pressure very well - doesn't seem to be leaking back gas to the tank or from any of the injectors. still rumbles on startup after sitting while hot. turn it of and restart a few times or wait while idling and the misfire clears. always cylinder 2 po302. thinking about the o2 sensor thing Pat - ill switch the plugs left and right upstream o2s tomorrow and see if the misfire moves. Link to comment Share on other sites More sharing options...
deltaR50 Posted June 29, 2015 Share Posted June 29, 2015 check cts Link to comment Share on other sites More sharing options...
JeffsR50 Posted June 29, 2015 Author Share Posted June 29, 2015 Switched plugs for o2 sensors, misfire stayed on #2. hmmm. Thanks deltaR50, I can do that (I did replace it less than a year ago, but of course that doesnt mean it isnt wonky) but it does seem to communicate ok with the fast idle cam I did back offf the fast idle cam screws after installing the new cts, to get the idle arm back to the factory screw on the throttle body, not sure maybe I went too far n that might have messed up my warm idle? -although when we are up to temp and running down the road - she idles great - 750-800 rpm no problem, no stalling etc thinking about doing the cheap cigar smoke test on my intake - did the seafoam trick over the weekend, if the exhaust manifold is leaking I sure didnt see it Link to comment Share on other sites More sharing options...
JeffsR50 Posted June 29, 2015 Author Share Posted June 29, 2015 Theres still this very interesting sidenote- whenever the misfire happens, the priming of the fuel pump has a distinct 'gurgle' in the fuel tank. almost as if the pump itself is releasing air bubbles as it primes.? - like today, I just ran an errand, came back out, turn the key notice regular pump noise no gurgle - no misfire runs perfect. wait 15 minutes.... turn the key to prime the pump - gurgle gurgle in the tank - misfire #2 Link to comment Share on other sites More sharing options...
Kingman Posted July 1, 2015 Share Posted July 1, 2015 Haven't read back yet to refresh my memory, so sorry if it's been covered. Has the rubber hose between the pump and hard line in the tank been checked? Link to comment Share on other sites More sharing options...
JeffsR50 Posted July 1, 2015 Author Share Posted July 1, 2015 Haven't read back yet to refresh my memory, so sorry if it's been covered. Has the rubber hose between the pump and hard line in the tank been checked? thanks kingman - hmm not that line in particular, but I have tested the fuel pressure which seems to hold steady both during and after running. - Also unplugged the fpr tube - fuel pressure increased like the service manual said it should. also really sprayed some carb cleaner around my intake connections and gasket trying to find a leak today - no avail! - thinking about the cheap cigar smoke test next. - also considering the downstream o2 sensors maybe? looked at freeze frame STFT again today and it was +25 on bank 2 - jeez only misfires on warm start after sitting for a few. - if I come back and start it within a few minutes its fine - 20 min in the sun and I have a misfire for sure. restart a few times and it clears Link to comment Share on other sites More sharing options...
fixinto Posted July 6, 2015 Share Posted July 6, 2015 OK, this is a new thing. Ask yourself "what did i change or mess with before this started happening" I know you messed with a lot of stuff before you made it to the vacuum cut valve for the hard start problem. OR did it start directly after the cut valve replacement? I was going to suggest that the Long term trims are just needing to adjust for no vacuum leak at start up, but its only bank 2. So what would cause lack of fuel on bank two when the truck is warm. I keep coming back to injector problems. The down stream O2 don't control fuel trims at all on our ride, they r there for emissions monitoring only. "under normal circumstances" so that leaves you with poor fuel delivery on bank two. you said you replaced the number 2 cylinder injector? what if its bank 2, so it could of been 2, 4, or 6. u went all that way and swapped the wrong one? May be worth investigating. The only reason i keep saying bank two is because i didn't think we could monitor each cylinder on a misfire, but i havent had misfire codes on mine so i havent seen it first hand. it wouldn't be spark because it is adding fuel. so we are left with, number 2 wiring harness issue, but you confirmed your number 2 injector was clicking away. I could be wrong but bank two cylinder misfire from a lean condition fits here, and there are 2 more injectors there. Maybe one of those are not energizing properly when hot. I am not sure, I am reaching a little or maybe even a lot. but bank 2 fuel trims match my theory. I am out of ideas right now. I will check back every now and then to see what the deal is. But hopefully my rambling will at least get you headed in the right direction. Good Luck and please let me know Pat Link to comment Share on other sites More sharing options...
fixinto Posted July 7, 2015 Share Posted July 7, 2015 Also, there is a rubber tube in the front and the back connecting the rails together. The manual says do not disassemble blah blah blah. However.....what if the rear tube is clogged to the even number cylinder rail? then misfire till everything gets up to speed and the fuel regulator closes to get max pressure once vacuum drops. LONG shot again. but im running out of things that are bank 2 related. almost has to be an injector clogged, or the fuel to the rail isnt happy. but if it were a "bad injector" or "bad wiring" it wouldnt line out once it stumbles and misfires. It would generally misfire all the time or work all the time. unless the wiring is "just now" going bad or a little loose and the vibrations cause it, but thats pretty slim. so im leaning toward a clogged injector bank 2 or clogged rail delivery. after the ecu has the initial +20 it makes it rich enough to get rid of the misfire and lean reading on the O2 so it smooths out. hmm thats all i got right now man. hope it helps. pat Link to comment Share on other sites More sharing options...
JeffsR50 Posted July 7, 2015 Author Share Posted July 7, 2015 thanks pat - yep I like the fuel rail clog idea - sounds like a possibility. however- I did the cheap cigar leak test on the intake manifold - and did find that the little tube at the bottom of the egr control valve was leaking! it was on there, but it fit loose - so I did replace that little chunk of hose havent really had the misfire since, but its been alot cooler here too- this does certainly seem to be much worse when its hot out - really really hoping that the little egr tube does it. (please please please) this is certainly my 'bitch about my truck' thread - but the truck has really been running great for the most part. Next weekend is my new cv joint install - got to get her ready for some bouncin up the mountain. thanks again man Ill update after it gets warmer n I find out for sure. Link to comment Share on other sites More sharing options...
fixinto Posted July 9, 2015 Share Posted July 9, 2015 cool i hope that fixes it, fingers are crossed. but thinking about it logically, i see misfires in your future ;P reason being its only one bank. usually a vacuum leak bad enough to misfire causes misfire on both banks due to the way our intake system is set up. but here is to hope, i even have a slim theory to maybe fit it. The EGR tube "metal one connecting to the egr valve" could be sucking clean air in through the egr vacuum leak and back into the exhaust manifold causing too much O2 to be read on that sensor. =) So slim as it may be, it is possible that you are good to go. Pat Link to comment Share on other sites More sharing options...
mechanicalbaron Posted July 9, 2015 Share Posted July 9, 2015 Did a little research on your problem, and after reading through the thread and looking at the esm at work I would like to throw out there that maybe the timing belt is off one tooth on one of the cam sprockets or possibly the cam sprockets are swapped? Both can certainly cause your problem. Easy enough to check as one side (bank) of the engine will have less compression than the other side. But this is just a random thought. Sent from my SCH-I535 using Tapatalk 1 Link to comment Share on other sites More sharing options...
fixinto Posted July 10, 2015 Share Posted July 10, 2015 Good point, ^ i hadn't even thought of that. pat 1 Link to comment Share on other sites More sharing options...
mechanicalbaron Posted July 10, 2015 Share Posted July 10, 2015 There are lots of things that I was looking at, disregard the crank sensor, that is only used for OBD II missfire per the ESM. If it was a ECCS relay then it wouldn't matter if you use a starting fluid to help start. And it seems that you've covered mostly everything else. You have to look at what the engine needs to fire, compression, spark and proper timing for a 4 stroke engine. If you downloaded the ESM there is a chart for symptom diagnostics for long start when hot. However there is nothing that touches on timing belts being off timing. I've seen problems resulting from that causing misfire, long cranking time and rough running. Deal with stuff like this alot and at the point your at that is the next thing I would look at. Not saying that's your problem, however it should be ruled out. Additionally if when the engine is running at idle and you can hear a rattle from the timing cover or distributor area you need to ret the timing belt. And a factory belt is what I would recommend. Ask for value advantage from nissan. Hope that helps. Sent from my SCH-I535 using Tapatalk Link to comment Share on other sites More sharing options...
JeffsR50 Posted July 10, 2015 Author Share Posted July 10, 2015 according to the sticker under the hood my timing belt was repl at 90k - Im at 140k so yeah maybe I need to look at tension - hmm, just wondering though, if I had jumped a tooth, wouldn't my misfire be more consistent? she runs and idles great once were goin down the road. any way of checking for a jumped tooth without taking her all apart? Yep Pat you were right, misfire is back but according to my freeze frame at the p0302 cyl 2 msfire, my fuel trim is back normal (perhaps my new egr tube straightened that out) again, hard starts are completely gone - she starts every time now -just the pesky misfire for a minute when starting hot. she does run smooth but might get a cheap harbor freight timing light just for giggles. Ill also have a look this weekend at the fuel hoses to the rail - thanks guys much appreciated Link to comment Share on other sites More sharing options...
mechanicalbaron Posted July 10, 2015 Share Posted July 10, 2015 Your coming up on the millage fur a t-belt replacement. 60k IIRC, compression test would be the easiest way to check. But if the long start is fixed then you probably should look more into the misfire issue. Do you smell gas? Can you check injector resistance? If you look under the intake behind the distributor does the injector connector look ok? Those connectors are known to get corroded, had to replace all of mine. Compression test still wouldn't hurt, I'm sure you can get a cheap tester at harbor freight. Sent from my SCH-I535 using Tapatalk Link to comment Share on other sites More sharing options...
fixinto Posted July 11, 2015 Share Posted July 11, 2015 T belt is 100k for R50 IIRC. Jeff, A timing light will just tell you that the crank is in time with the number 1 ignition. I personally would also think if it was a tooth off it would be an all the time thing as well. Same with a compression leak on that cylinder. P0302 cylinder 2 misfire. I didnt realize our ECU setup could monitor individual cylinders, thats kind of cool. So 2 steps. 1 figure out if the misfire is due to fuel or spark. 2. find out what the heck it is. so the theory about the clogged rail may be out, because it seems like all of them would be fuel starved, not just the #2. Ohming the injectors seems ok. you don't have to look up what the resistance are, just hit 3 and they should all read pretty much the same. change the number 2 spark plug wire with another one to see if it follows the wire. that will eliminate that if it isnt faulty. For instance, just swap the number 2 and number 4 on plugs and the dizzy. "if you can get the length out of them" or if you changed them and saved some of the old ones as backup like i do, swap it with an old one. You cant really reach the injector plugs on the even side without ripping the intake off. kindof a long way to go for an ohm reading. I would do that after i ran out of options, if the injector plug was damaged or corroded, it seems like the misfire would be more consistent. General air intake, or General fuel delivery is out because it would take out bother sides of the motor, so its something specific to the number 2. While you are pulling the plug wires to swap them, inspect the number 2 spark plug, during the starter fluid days, it may have simply fouled that plug for whatever reason. while you have the plug out, get a step stool or something and look down in the spark plug hole and see if you see any liquid. If you do see liquid reflecting back at you, shake the truck and see if the liquid moves easily, if not, its oil, meaning your valve stem seal is probably leaking badly after its warmed up, or coolant if it moves easily meaning the dreaded Head gasket leak. Now that the hard start is fixed "hopefully" I am starting to think maybe it is something easy. Let me get this right, u have new plugs, wires, and dizzy all done as maintenance while chasing the hard start? I am curious as to when it started doing it. when it was having a problem with hard starts and you used starter fluid, did it misfire when it started? or did it start misfiring and stumbling on fire up after you replaced the vacuum cut valve? Just as a precaution double check all of your work back there, im not sure why it would cause a #2 cylinder misfire, but the gurgle gurgle when it misfires is still bugging me. the thing that keeps bugging me is how a vacuum cut valve or any of that system in general would cause a number 2 misfire. YOu said you got your obdII ready at HF? next time you have an issue stop at an auto parts store and have them read the code for you just to verify the OBD you bought is doing its job correctly. Some things from there i would by all day long, other things, well not so much, i have seen some fairly shady quality control stuff from there. Rear is dragging on a Friday night have a large list of "to do" for tomorrow, going to hit it. Hopefully you get her lined out man Pat Link to comment Share on other sites More sharing options...
mechanicalbaron Posted July 11, 2015 Share Posted July 11, 2015 T belt is 100k for R50 IIRC. Jeff, A timing light will just tell you that the crank is in time with the number 1 ignition. I personally would also think if it was a tooth off it would be an all the time thing as well. Same with a compression leak on that cylinder. P0302 cylinder 2 misfire. I didnt realize our ECU setup could monitor individual cylinders, thats kind of cool. So 2 steps. 1 figure out if the misfire is due to fuel or spark. 2. find out what the heck it is. so the theory about the clogged rail may be out, because it seems like all of them would be fuel starved, not just the #2. Ohming the injectors seems ok. you don't have to look up what the resistance are, just hit 3 and they should all read pretty much the same. change the number 2 spark plug wire with another one to see if it follows the wire. that will eliminate that if it isnt faulty. For instance, just swap the number 2 and number 4 on plugs and the dizzy. "if you can get the length out of them" or if you changed them and saved some of the old ones as backup like i do, swap it with an old one. You cant really reach the injector plugs on the even side without ripping the intake off. kindof a long way to go for an ohm reading. I would do that after i ran out of options, if the injector plug was damaged or corroded, it seems like the misfire would be more consistent. General air intake, or General fuel delivery is out because it would take out bother sides of the motor, so its something specific to the number 2. While you are pulling the plug wires to swap them, inspect the number 2 spark plug, during the starter fluid days, it may have simply fouled that plug for whatever reason. while you have the plug out, get a step stool or something and look down in the spark plug hole and see if you see any liquid. If you do see liquid reflecting back at you, shake the truck and see if the liquid moves easily, if not, its oil, meaning your valve stem seal is probably leaking badly after its warmed up, or coolant if it moves easily meaning the dreaded Head gasket leak. Now that the hard start is fixed "hopefully" I am starting to think maybe it is something easy. Let me get this right, u have new plugs, wires, and dizzy all done as maintenance while chasing the hard start? I am curious as to when it started doing it. when it was having a problem with hard starts and you used starter fluid, did it misfire when it started? or did it start misfiring and stumbling on fire up after you replaced the vacuum cut valve? Just as a precaution double check all of your work back there, im not sure why it would cause a #2 cylinder misfire, but the gurgle gurgle when it misfires is still bugging me. the thing that keeps bugging me is how a vacuum cut valve or any of that system in general would cause a number 2 misfire. YOu said you got your obdII ready at HF? next time you have an issue stop at an auto parts store and have them read the code for you just to verify the OBD you bought is doing its job correctly. Some things from there i would by all day long, other things, well not so much, i have seen some fairly shady quality control stuff from there. Rear is dragging on a Friday night have a large list of "to do" for tomorrow, going to hit it. Hopefully you get her lined out man Pat Ahaha, dogonnat, I was thinking a 3.0L, you sir are right on the money. The only thing I would disagree with is ohming out the injectors. Can be done through the harness on the right valve cover connector. Gotta work tomorrow so I'll look that up. I was thinking 3.0 for t-belt replacement but 3.3L is 100k. For some reason I was thinking 95 model year. However the fundamentals remain the same. Sent from my SCH-I535 using Tapatalk Link to comment Share on other sites More sharing options...
Kingman Posted July 11, 2015 Share Posted July 11, 2015 Tried smacking the NO. 2 injector when it's missing? Link to comment Share on other sites More sharing options...
mechanicalbaron Posted July 11, 2015 Share Posted July 11, 2015 Sent from my SCH-I535 using Tapatalk Link to comment Share on other sites More sharing options...
mechanicalbaron Posted July 11, 2015 Share Posted July 11, 2015 These are the two connectors that injector resistance can be measured and these pics are from a 97 pathfinder that was in the shop today. Sent from my SCH-I535 using Tapatalk Link to comment Share on other sites More sharing options...
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