Summary of no start/hard start??

[i68k]

not sure what code reader you have, or what the flashing circle means. if you had just previously cleared the codes, that evap system may not be 'ready'.

p0300 is random or multiple misfire, many misfires on one cylinder or multiple cylinders misfiring. do you feel the motor misfiring? say when you start it up when its really cold out? did you clear your misfire code last time? if you didnt, the next misfire will change from say cylinder 3 to a random/multiple misfire on the next misfire. does it have a steady misfire, or is it rather random? i know you moved around coilpacks, but have you changed your cam & crank sensors recently? these are common problems, and can cause random misfiring. how is your idle when the car is warm? hopefully your not getting oil in your cylinder 3 again, i would take a look and make sure theres no oil on the spark plug or coil pack. if theres oil on your piston, you have internal issues like bad headgasket, or fried oil rings.

EDIT: make sure you are installing/removing spark plugs when your motor is cold. you can use a little anti-seize on the threads as well, dont want one getting stuck.

[jacjm]

EQUUS INNOVA 3140 code reader, i forget exactly what it cost, but it was up around $200. it has too many features, really. extras complicate the simple things.
IF i get the car started, you DEFINITELY can feel the miss. it is steady at low RPM's, but seems to even out at higher RPM's. all the coil packs are back in their original positions, with the new iridium plugs. cylinders (piston tops) were clean. i never had oil in cylinder 3. dealer changed cam and crank sensors 8 or 10K miles ago. why am i not getting a more definitive code ?? i don't need an ECU to tell me there is a mis-fire,,,

[i68k]

cam and crank sensors are known to miss signals, which can cause a misfire. if its misfiring steady right from a cold start, its possible some wires are loose or you have failing coilpacks. coilpacks tend to only last 100k miles, maybe one or more is kicking out on you. when they start failing, its usually noticeable on very cold starts, they will misfire for 5-10 seconds before they start working, possibly youve past these beginning stages of coilpack failure. if this is your case, you either need new coilpacks, or you need to rebuild them. as long as your ignitor works, i believe you can rebuild them with new springs and capacitors.

i would clear your p0300 random misfire, once you clear this just check your ses light right away, it maybe a p0303 or something which can narrow down the problem, possibly get another ses code all together. backtracking, do you still have to 'half-throttle' to start the motor? have you done all 3 relearns in order successively (drive-by-wire only), maybe something didnt hold there? you did check your battery voltage motor on & off when you checked your terminals yes? any smoke coming from the tailpipe, black, blue, white, etc? hopefully you dont have a bad headgasket, or bad ecu.

[jacjm]

yes, i still give it gas (sometimes pumping furiously) to finally get it started. that is what leads me to believe it is fuel-related. then, a big puff of white smoke out the exhaust (unburnt fuel??). i haven't done any re-learns, guess i gotta research what that is all about. dec 24th i put sunoco 93 in it, and went on a long drive. it drives pretty good at about 55mph and up, as long as you are steady on the gas pedal, but if you let off for any reason, you can still feel the miss (sometimes bucking and sputtering, too). the starter is on its way out, now. too much cranking. haven't done any voltage testing yet. i can't find any time w/the holidays, and working so much (six 10's and an 8). plus, my girls car needs brakes-doing that today (merry xmas!). i will be able to look at it again later tonight. i will try to do what you suggest, but i can't take it apart too much, because i am gonna attempt to use it to go to work tomorrow, thru new years-i have no choice. thanks for all of your input, i will keep this post advised, and Merry Christmas to you and all of yours!

[jacjm]

i forgot--do you think water in the gas could be a factor ?? (my girl consistently used the "junk" cheapo gas). i think i will pick up a "noid" light, to see if the injectors are getting a signal (i think it is called that), unless there is another way to see if they are working properly. i had them apart in the summer, but never bench-tested them-only tried to clean them up. what are your thoughts on the IAC valve, and the EGR being too dirty ??

[JudoJohn]

i think you may have a head gasket failing. HG failures are very common on the QG. that may be why you are getting the miss in the cylinder...that would explain the puff of smoke on startup.

[i68k]

a clogged iacv or egr could cause a no-start or stalling situations, you can clean these out. its possible you have a bad coilpack or cam/crank sensor failing. however, like judojohn said, there's usually only 2 reasons to get white smoke from the tailpipe, there's moisture in the exhaust/fuel, or youre burning coolant. hopefully youre keeping an eye on your oil and coolant levels. i know when i had to use the throttle to startup, i had a bad crank sensor that was missing signals, there was recall and ecu reprogram for it. you can test your headgasket with a compression test, then a leakdown test. it is possible to have an evap issue as well, do you hear any vacuum or air pressure leaks anywhere?

[jacjm]

i am 99.99% sure it is not a head gasket. BUT, i am gonna get a compression tester, anyway. the old set of plugs showed no signs of anything abnormal. the piston tops were not wet. no oil anywhere. so, i am gonna check compression, spark, and then back to the fuel/air. the only time i have ever seen the puff of white smoke is when i have had to give it gas to start. also, if i ever get time i want to pick up some used coil packs (and maybe some injectors) from a pull-it yard, to experiment with. change them around one at a time. (see if maybe i can rebuild them, like you said) after i am POSITIVE i have good compression and spark, i will have to start cleaning everything related to the fuel/air ratio. thanks for helping, with your input. i am more frustrated than a one-legged ethiopian watching a donut roll down a hill!! (lord, i apologize!)

[i68k]

you can rebuild the coilpacks, im not sure about the injectors, i know they can be cleaned out somehow. last time i bought the rebuild kit, it was about $30 to rebuild 4 coilpacks, includes springs and capacitors, assuming your ignitors work. have you cleaned your maf recently? use only cnc maf cleaner, anything else with ruin the maf, disconnect your negative battery before disconnecting the maf. follow the directions, make sure its dry before reinstall. the maf is metering your air, and your primary o2 sensors are controlling your afr. dont forget to keep an eye on your battery as well with all the cranking and no starting, might want to jump it if the battery is becoming weak. how did yo make out after the 3 relearns? did it start better, did it get worse?

EDIT: i cant find the how-to rebuild the 1.8L coilpacks, but here's a 2.5L coilpack rebuild thread:
http://www.b15u.com/sentra-specific-...down-pics.html

[jacjm]

i will post when i get to fool with it again--working 10hours a day x7 for now, plus an hour drive each way. not a lotta time left over for car work. i still have to track down the re-learns. bought a compression tester, tho.

[i68k]

here's the relearns:
http://www.b15u.com/sentra-specific-...e-relearn.html

everything else is in the fsm. all the specs for the relearns, compression, etc.

you can get the fsm:
nicoclub.com/fsm
allsentra.com/fsm

[jacjm]

12/ 28 / 2012 AFTER WORK, I CHECKED THE CODES AGAIN. got a P0301,,,YES, i finally have something to start with. cleared the code. drove home. checked again and it was back to P0300-WTH!,, SO, i pulled the #1 plug and put it back into the COP boot, and hooked up my compression gage. had my g/f crank it over ( i pulled the fuel pump fuse, also) and had what looked like a weak, random spark, with 119 psi on the gage. so, i bought a new coilpack--$66-- and put it in. got it started, and still had the mis-fire. that is when i noticed the fuel pressure regulator was leaking. (huh?) so i took it off, and replaced it with the old one i took out back in the summer (i was trying to fix the hard start, and had replaced that, too). started it up, AND NO MORE MISFIRE!! (for now). took it for a long, hard drive, and it ran good, with no CEL light. --so, that explains the pedal pumping, and fuel smell, getting it started-i suppose. it is still hard to start, but at least it is running better. still have to do the re-learns, i guess. maybe tonight, after i see how it does to and from work.

[i68k]

the relearns will recalibrate your throttle body with the ecu, when you do all 3 successfully in order. once you do them, you can see how long they hold, as other sensors, like maf, o2, etc, the ecu will adjust your fuel trim from reading these sensors. also, make sure you warm the motor up to operating temp before doing the idle relearn, so it finds true idle.

glad you have found your leak, i would double check the rest of the fuel lines for any more leakage. assuming you have no leaks, you can prime your fuel to startup. its goes something like keySTART for 2-3 seconds, and then while keySTART, press clutchDOWN to start the motor.

however, 120psi is still rather low for a compression test. its possible its just your tester not calibrated. dont forget to keep an eye on your oil and coolant levels.

[jacjm]

quick update: the car runs pretty good, for now. naturally, other things have decided to go haywire. after i solved some of the problems now i can only gas up to about halfway, then it won't take any more gas, AND i get the gurgling sounds before it pukes gas back at me. i bought the whole vapor canister and related items off another 2002, and bench-tested the vent control valve. i could hear it opening and closing, and i put it on. haven't tried to gas up with it on ,tho, (no codes for this problem, either). service engine soon light comes on with P0175, system rich. cleaned the MAF with CNC MAF cleaner, no change, code comes right back. battery voltage not running=12.65 dc, at idle= 13.85dc, so this seems adequate. i tried the re-learns, and i am pretty sure i got them correct. (how would i know?). used PERMATEX dielectric grease on all the connections i had apart. this car never quits giving codes. fix one thing, two others crap out.

[i68k]

P0175 NISSAN - Fuel Injection System Too Rich Bank 2

if youre not sure about doing the relearns correctly, you can do them again, or multiple times. this code could be caused by a bad maf, but it could also be caused directly by a bad primary o2 sensor, or multiple bad o2 sensors.

however, if you notice your voltage is below normal range, its possible electrical sensors are not being supplied adequate voltage, and could cause malfunction codes. it appears your battery voltage is great, but your charging system is not working properly. if your battery is 12.65V, while charging it should be over 14.6V, but youre only getting 13.8V which is outside of normal operation. check the wires going to your alternator, there should be a wire harness, make sure its plugged in good and not overly dirty, also there is a LIVE WIRE under the red cap, disconnect your positive battery terminal and then make sure that bolt is tight. its possible you may just need a new alternator, or rebuilt alternator. i would start with the charging system instead of chasing codes, the charging system can cause any random sensor to lose voltage and get reported by the ecu for failure. essentially, your maf or o2 sensors could be losing voltage, causing the injection to run rich, which gets detected by the ecu and gives you the rich code. it also goes with your moto 'fix one thing, two other crap out' or just lose power