vq25det m35 stagea, crank but no start

[Gibbsygoodness]

G'day guys, me again with the non running vq25det stagea, starting to nail down on components trying to diagnose my issue and noticed something while removing and cleaning my crank sensor

i noticed metal fragments on the magnetic part of the sensor, so i cleaned then off, refitted the sensor and tried to give it a strart, and i noticed for the first time in a while it fired and tried to start on the first try, but on the second and third there was no fire, so i took out the sensor again, cleaned it again and same thing, fired first try, still no start, but on second and thirrd try its again not firing

so my question is, could my sensor be faulty? what else could be causing this?

 

[admS15]

Its usually crank or cam sensors.

Google instructions on how to pull fault codes from the ecu and it should pinpoint which sensor it is. There's a dance you do with the acc pedal and ignition key. Best to use a stopwatch when trying to do it. All info is available on this site via Google.

[Gibbsygoodness]

@admS15 thankyou very much, i have just done that and came back with a code of 0115, which is 'Engine Coolant Temperature Circuit Malfunction" everything i see says that wont stop the car from starting though, it will just run rough until it warms up? i have tried to erase the code using the mentioned method on the forum, and that has not worked (yet).. none the less, thankyou very much for the tip! i shall keep trying to diagnose the issue, or call lube or something

[admS15]

35 minutes ago, Gibbsygoodness said:

@admS15 thankyou very much, i have just done that and came back with a code of 0115, which is 'Engine Coolant Temperature Circuit Malfunction" everything i see says that wont stop the car from starting though, it will just run rough until it warms up? i have tried to erase the code using the mentioned method on the forum, and that has not worked (yet).. none the less, thankyou very much for the tip! i shall keep trying to diagnose the issue, or call lube or something

Try unplugging the coolant temp sensor and then try starting

[Gibbsygoodness]

@admS15 thanks again, and i hate to be that guy, but do you know where i could find the sensor? i believe its near the thermostat but i cant seem to find anything besides what seems to be a broken plug, which could be both what im looking for and my issue

[admS15]

There's a pipe at the rear of the engine that connects the two banks, the coolant sensor is in that. It could also be the wiring that goes to the sensor, that should be inspected. Here is a diagram with the location highlighted.

[Gibbsygoodness]

Hey @admS15, thanks for that tip, was a pain to remove but i got it, now here's what happened.

after removing just the plug from the sensor, it started almost no hesitation a ran rather fine besides a slight miss, so i took the sensor out and down to sprint auto, grabbed a new one as they're rather cheap, i was supplied with a cts-031 which seems to be correct and once i fitted it, it did start and run for a while but cut out after a few minutes and it looked like the temp gauge wasn't working either, but once again it continued to not start after that, i again removed the plug from the sensor and it started again but ran rough.. not quite sure where to go from here, the opinion from my group is spark plugs and coil packs but again i just really don't know

[admS15]

Man, im out of ideas. Have you checked the wiring loom going to the sensor. Your original code was relating to coolant temp circuit. The new sensor you got may not be 100% compatible either. I like to use genuine Nissan stuff for troubleshooting. You could go to a wreckers yard and try match up a sensor out of another Nissan like a Maxima or pulsar etc. 

Would be good to check what the actual sensor is reading. A scan tool that can read m35's will required (consult or snap on). There is a phone app that works via Bluetooth obd adaptor (elm 327) called hobdrive. The demo version should enable you to see what the temp is doing.