vq35 Posted June 6, 2012 Share Posted June 6, 2012 (edited) Aside from the last rear right bracket, it was pretty straight forward albeit LONG and awkward. My intention was to redo the gaskets/spark plugs (that a local shop claims they did). I have finally reached my destination which was to redo everything the shop did to ensure proper torq and sequence for everything AND look into the new codes that developed after they messed with it. (knock sensor/purge valve plus the previous intake timing sensor codes - bought new purge valve and intake timing sensor but wanted to see what the deal is on the knock sensor at $300 - maybe it was not placed back properly etc) So now that the lower intake is off and I am staring at the head and fuel rail. No sign of the pcv valve (which they failed to change) nor the knock sensor .........can anyone point this out please via picture or fsm and how exactly to extract them...... thanks Edited June 6, 2012 by vq35 Link to comment Share on other sites More sharing options...
vq35 Posted June 6, 2012 Author Share Posted June 6, 2012 Anyone have a picture of lower intake manifold off showing the location of the knock sensor? Link to comment Share on other sites More sharing options...
Towncivilian Posted June 6, 2012 Share Posted June 6, 2012 (edited) KS is in the bottom center. If you are replacing your PCV valve, you need the rubber grommet that goes around it (11812-41B00 INSULATOR-). You can measure the resistance of the knock sensor at its terminals. See EC-327, step 4. EC-323 pictures the knock sensor's location. Edited June 6, 2012 by Towncivilian Link to comment Share on other sites More sharing options...
vq35 Posted June 6, 2012 Author Share Posted June 6, 2012 (edited) wicked and my apologies for the multi site post - thanks and please disregard the other this looks like one step lower than I thought, so this does mean taking the fuel rail off....... thats a little more ......is it at all possible to NOT mess with the rail?? what are the steps to rail removal - if straight forward, then I feel confident going at it??!! any suggestions appreciated Edited June 6, 2012 by vq35 Link to comment Share on other sites More sharing options...
Slartibartfast Posted June 6, 2012 Share Posted June 6, 2012 I've never been into a VQ (hell, I've never even been into a lawnmower) but after seeing my dad spray himself with gas, I can say this: unless you pulled the gas pump fuse and ran it until it died before tearing into it, there's probably still pressure in the fuel line. Not much you can do about that at this point, but be prepared, wherever you open it up, it's likely to spray a little gas. That said, the more stuff you get out of your way, the more enjoyable the whole thing will be... there are few things more frustrating than working around stuff. Link to comment Share on other sites More sharing options...
vq35 Posted June 6, 2012 Author Share Posted June 6, 2012 I've never been into a VQ (hell, I've never even been into a lawnmower) but after seeing my dad spray himself with gas, I can say this: unless you pulled the gas pump fuse and ran it until it died before tearing into it, there's probably still pressure in the fuel line. Not much you can do about that at this point, but be prepared, wherever you open it up, it's likely to spray a little gas. That said, the more stuff you get out of your way, the more enjoyable the whole thing will be... there are few things more frustrating than working around stuff. LoL.... I was picturing that very scenario but rationalized my way out of it by calling meself a BIG OLE SISSY ..... that got me all angry and rev'd up ..... then it turned to I just dont want to do it anymore after reading your post. Thanks for the heads up though! Link to comment Share on other sites More sharing options...
02silverpathy Posted June 7, 2012 Share Posted June 7, 2012 (edited) You may as well get at that rear thermostat while your that far...and the PCV valve too. In this pic the PCV can't be seen but is on the rear of the valve cover on the left...it is a PITA. Edited June 7, 2012 by 02silverpathy Link to comment Share on other sites More sharing options...
vq35 Posted June 7, 2012 Author Share Posted June 7, 2012 managed to get at the pcv and the rear thermostat was what started this whole process (rear coolant leak) - then towncivilian pointed out the grommet that the pcv goes into (waiting for the dealer to stock it) my main problem is the fuel rail/lines, does anyone have a step by step of this??? the rail is in the way of the knock sensor and I need some guidance to re/re the fuel rail and what I will need to replace when I do so?? any more grommets or similar ?? once I have the rail off, should I have them cleaned and by whom? any help appreciated Link to comment Share on other sites More sharing options...
Towncivilian Posted June 7, 2012 Share Posted June 7, 2012 As far as I know there hasn't been any guides on removing the fuel tube and intake manifold. The FSM would be your best help here. It looks like there are a couple more gaskets - [14035] GASKET-MANIFOLD. If you want the exact part number you can PM me your VIN. If the fuel pressure regulator has to come off, there are O-rings which must be replaced and then lubricated with new engine oil prior to their installation. Link to comment Share on other sites More sharing options...
vq35 Posted June 10, 2012 Author Share Posted June 10, 2012 Ok so managed to change the pcv and grommet - could not get past fuel rail but noticed there were 2 rubber insulators (they were just disregarded) that the bracket holding the fuel regulator and fuel damper sit on. I placed them in their proper places and there seems to be an improvement to my surge (upon accelerating). Does anyone know if the misalignment of the regulator and damper will have an affect on acceleration.......... Link to comment Share on other sites More sharing options...
vq35 Posted June 19, 2012 Author Share Posted June 19, 2012 (edited) Ok so here is the update to this and I will repost questions. I did not get to the knock sensor because the fuel rail was in the way and I was not sure about its removal. I re used old gaskets which seemed intact and wear free. Now I bought the following to go back in and conquer the knock sensor replacement. 12 rubber rings (upper and lower) for the actual fuel injectors, once off 4 o rings on the way to the pressure regulator and damper (new engine oil on hand) 4 poly insulators that the rail sits on 6 injector clips and since I am down there, will do the valve cover gasket also and all the way back up to throttle body did the sequence for tighteing last round but not torqued to spec (yes, I guessed!) this time will use torque wrench knock sensor WILL NOT be oe though as they are around $50-100 aftermarket (anyone bought knock sensor aftermarket???) any information on performance or experience with aftermarket KS?? appreciated couple of questions 1 the maxima maf i replaced about 1.5-2 yrs ago but am worried it might go again, any experience with aftermarket MAF?? 2 if there are no codes or issues with the o2 sensors, can I simply replace all four, I have a leak on the top portion of the cat so I got all the exhaust gaskets (aftermarket cat back exhaust is pretty new) and since I am there, wanted to change the o2 sensors without the dealer reflash ...is this possible??? 3 how do I check the voltages for all the sensors?? where can I get the spec/parameters of peak voltage for the sensors in the engine?? what tool do I need?? 4 when I remove the fuel rail (will remove the fuel pump fuse and use as much fuel as is in the system, the car shuts off then this will decrease the amount of fuel that will shoot into my eyes...anyone have any tips for this particular situation, will there be damage fro the spilled fuel on sensors parts etc? thanks folks I dont care until I get my power back, I will keep at it, one way or another last question, I scanned repeatedly after cycling the car and the knock sensor code keeps coming back 0325, so this means either the physical sensor is broken or the harness is damaged, are these things common as the mechanic went that far and actually reached the knock sensor (so could have damaged or broken the knock sensor) but the worse scenario is the harness, as I would have no idea how to check or fix it, any insights appreciated on inspecting and potentially fixing a broken harness¨????!!!!! thanks Edited June 19, 2012 by vq35 Link to comment Share on other sites More sharing options...
Slartibartfast Posted June 19, 2012 Share Posted June 19, 2012 To check the harness, I'd go through the service manual wiring section and try to figure out where the wires from the knock sensor go (presumably a set of pins in the plug for the computer). Then take a voltmeter, set it to continuity/ohms, and check each wire. You may need a few alligator clips or something to extend the little probes. I'm not sure how I'd repair the wiring harness... it would likely fail near a plug (move the plug, see if it cuts in/out). Some plugs you can pop the pins out and reconnect them... I've never gotten a Pathfinder plug apart that far, though. Maybe check a junkyard and pull the harness, or even just the end of it (and splice/solder it into what's there). I don't imagine the fuel spray would damage much (though I wouldn't leave it on paint for too long), but all the same I'd wrap a towel or something around the line when you disconnect it to catch any potential spray. It'll keep it out of your eyes and lungs too. Link to comment Share on other sites More sharing options...
vq35 Posted June 19, 2012 Author Share Posted June 19, 2012 ok sounds good still have exhaust leak to tackle though and replacement of o2 sensors = reflash at dealer?? guy at service said that as long as there are no 02 sensor codes, there 'should' be no problems......... Link to comment Share on other sites More sharing options...
vq35 Posted June 20, 2012 Author Share Posted June 20, 2012 So anyone know if you need a reflash if all 4 o2 sensors are changed?? Link to comment Share on other sites More sharing options...
Towncivilian Posted June 20, 2012 Share Posted June 20, 2012 No, you shouldn't need one. Maybe if O2 sensor codes pop back up within a few hundred miles, but that TSB is only for rear O2 sensor replacement with OEM parts. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now