quickhelp
10-05-2008, 05:02 PM
2003 nissan sentra. this is not my car, it is my gf's friends. but i figured i would try to get some help here. she needs the car soon, and of course i got stuck fixing it lol.
anyways, as i said, 2003 nissan sentra 1.8l engine, about 65k on the odometer. originally she said the car needed a battery and asked if i can put one in. i said sure....put it in, no crank, no start. she said it will run when jumped though since she had someone jump it and it ran fine. anyways, i clean the battery terminals as there was some corrosion on them (more than i originally saw, ie, was all jacked on the inner side of the terminal).
now car cranks over fine, but doesnt start. hooked up my scantool. no dtcs (besides a p0420 for the cat, which she needs to get taken care of before the emissions warranty runs out). i thought, well maybe its a crank sensor issue, since in my little research ive done it seems to be common on these cars. check the scantool, watching engine rpm, i crank the car over. sure enough, engine speed varies as it should. so its not the crank sensor.
now i think ill check for fuel....but i cant find any shrader valve on the fuel rail (anyone know where it is, so i can hook up a pressure gauge and actually see what kind of pressure im dealing with?). anyways i find a junction near the firewall, separate the two fuel lines and crank the car over again. fuel pours out (again, dont know the pressure, but fuel did squirt out. yes, a very redneck way of determining if there is fuel pressure)
hmm, maybe there is no spark. i pull a coil, but alass, all my tools are at work (besides the one ratchet and 10mm socket i brough), not even a spark plug socket around :mad: . still i try to see if i can get some spark. i run a small wire inside the coil, and then place the other side onto the block. if there is spark, i should see it on the block lol. i have someone crank the car over, and it seems as if there is no spark (ill make sure on monday, when i actually can bring some tools over)
so what exactly could be causing the no spark at this point (dont know much about nissans)? i assume it could either be the wiring harness running to the coils or the pcm or ecu? i have the flow chart on testing the pcm/ecu and which pins should give what values, but id hate to waste my time on it if its not even where i should be.
ps: if i disconnect all fuel injectors and crank it over its a real quick crank. however, if i leave the fuel injectors connected as if im actually trying to use the car and crank it, the car cranks real quickly, and then after a second or two it starts to bog a little bit, but no matter how much i crank it doesnt start and just continues to bog. it does however sound like its desperately trying to start, but just cant do it. if i turn it off and try to crank again, even just 1 second later, the same thing happens, quick crank then bog ALMOST starting.
WOW, sorry for the long first post, but im trying to get all the info out :eek: thanks in advance to the guys that will post advice and werent scared away by the long post
anyways, as i said, 2003 nissan sentra 1.8l engine, about 65k on the odometer. originally she said the car needed a battery and asked if i can put one in. i said sure....put it in, no crank, no start. she said it will run when jumped though since she had someone jump it and it ran fine. anyways, i clean the battery terminals as there was some corrosion on them (more than i originally saw, ie, was all jacked on the inner side of the terminal).
now car cranks over fine, but doesnt start. hooked up my scantool. no dtcs (besides a p0420 for the cat, which she needs to get taken care of before the emissions warranty runs out). i thought, well maybe its a crank sensor issue, since in my little research ive done it seems to be common on these cars. check the scantool, watching engine rpm, i crank the car over. sure enough, engine speed varies as it should. so its not the crank sensor.
now i think ill check for fuel....but i cant find any shrader valve on the fuel rail (anyone know where it is, so i can hook up a pressure gauge and actually see what kind of pressure im dealing with?). anyways i find a junction near the firewall, separate the two fuel lines and crank the car over again. fuel pours out (again, dont know the pressure, but fuel did squirt out. yes, a very redneck way of determining if there is fuel pressure)
hmm, maybe there is no spark. i pull a coil, but alass, all my tools are at work (besides the one ratchet and 10mm socket i brough), not even a spark plug socket around :mad: . still i try to see if i can get some spark. i run a small wire inside the coil, and then place the other side onto the block. if there is spark, i should see it on the block lol. i have someone crank the car over, and it seems as if there is no spark (ill make sure on monday, when i actually can bring some tools over)
so what exactly could be causing the no spark at this point (dont know much about nissans)? i assume it could either be the wiring harness running to the coils or the pcm or ecu? i have the flow chart on testing the pcm/ecu and which pins should give what values, but id hate to waste my time on it if its not even where i should be.
ps: if i disconnect all fuel injectors and crank it over its a real quick crank. however, if i leave the fuel injectors connected as if im actually trying to use the car and crank it, the car cranks real quickly, and then after a second or two it starts to bog a little bit, but no matter how much i crank it doesnt start and just continues to bog. it does however sound like its desperately trying to start, but just cant do it. if i turn it off and try to crank again, even just 1 second later, the same thing happens, quick crank then bog ALMOST starting.
WOW, sorry for the long first post, but im trying to get all the info out :eek: thanks in advance to the guys that will post advice and werent scared away by the long post