[sm4k]

2003 SpecV, ~115k miles. I bought the car with 114k on it, did an oil change, air filter, and replaced my crank angle and crank position sensors within the first 200 miles I owned it (after experiencing the "tachometer dropping to 0 while running" problem twice).

Car runs fine 99% of the time. I do have the prime the fuel pump (turn the ignition to 'on' for a few seconds, hear the pump whine to life, then start the car) otherwise it takes a bit to crank over.

The real problem is that occasionally it will misfire for a few seconds (5-45). This can happen right when the vehicle is started, it can happen at a stop light, and once it happened while I was on the highway.

Sometimes when I start it (seems to be exclusive to when the motor is already warm) I can smell fuel, very strongly, and then the car will start into the misfiring.

The biggest problem is that when it's misfiring, it may or may not trigger the SES light. When it does trigger the light, it's flashing (which I know means stop driving the car immediately), but once the misfire is over, or if I start the car after turning it off, the problem is gone and the light is off.

I remembered that the car had an aftermarket warranty and took it to a Nissan dealer explaining the problem. They have had a ***** of a time recreating the problem. They were eventually able to pull a "General Misfire" code, but other than that they have not been able to experience the fuel smell, or repeated misfiring.

I'm beyond frustrated at the situation, and this is the second time the Dealer has had the car. They know about and have checked my work on the sensors. I'm about to pull the trigger on this, just to see if it will help me collect enough data for them to know how to approach the problem. I've already surrendered the car to them for the rest of the holiday week, encouraging someone at the dealership to drive it as a personal car with their own logger plugged in.

Has anyone experienced this problem before, and/or can anyone point me in the direction of a reasonable ODBII logger to help me figure out what the hell is wrong?

 

[i68k]

2003 SpecV, ~115k miles. I bought the car with 114k on it, did an oil change, air filter, and replaced my crank angle and crank position sensors within the first 200 miles I owned it (after experiencing the "tachometer dropping to 0 while running" problem twice).

this is most likely your crank sensor, but it could be ecu, or some electrical issue or connection. these are very common problems. otherwise youd need to check the signal plate.

Car runs fine 99% of the time. I do have the prime the fuel pump (turn the ignition to 'on' for a few seconds, hear the pump whine to life, then start the car) otherwise it takes a bit to crank over.

this is normal, just keep priming. theres a couple of fixes, like check valves and stuff, but if you can prime, you should be good. the fuel just looses pressure in the lines fast.

The biggest problem is that when it's misfiring, it may or may not trigger the SES light. When it does trigger the light, it's flashing (which I know means stop driving the car immediately), but once the misfire is over, or if I start the car after turning it off, the problem is gone and the light is off.

Has anyone experienced this problem before, and/or can anyone point me in the direction of a reasonable ODBII logger to help me figure out what the hell is wrong?

yes, youre right, this is your biggest problem. when youre ses is flashing and there are no codes, its a sign of loss of power or failure. if your ecu does come back to life, saying you can drive it sometimes, then i would pull the ecu, make sure the wiring is good, rusting up ecus in not uncommon. then check your battery terminals and tiedowns for tightness, make sure theres good ground contact. check your voltage motor on and off. maybe pull on some wires when the car is idling, see if theres a static hesitation. have you checked anything else? cause really it could be one of many different sensors failed, possibly lost voltage.

 

[sm4k]

I'm not concerned about the other issues as I haven't seen the tach issue since I did the sensors, and the priming really isn't all that annoying now that I've developed the habit.

No, I haven't done anything else. Once I remembered that warranty it went straight to the dealer and resolution has stalled in their inability to recreate the problem (not faulting them, by any means).

I drove it earlier this evening to try and trigger the problem for them, and I noticed the clock had been reset, so I assume they've at the very least checked battery terminal tightness as it's likely been disconnected at some point.

if your ecu does come back to life, saying you can drive it sometimes

I'm not sure if this is what you mean, but the car has never died on me, it just misfires for a bit then either it works itself out before I can get pulled over, or I shut it off, let it sit and when I start it again, it's fine. When it's misfiring at start, as long as the SES isn't blinking at me I just let it idle and it works itself out.

 

[i68k]

i mean when your light is flashing, your ecu should be storing ses codes, normally so you can pull them to fix the problem. but youre saying, there was only misfire codes, which are common. if the ecu itself loses power or is faulty, those codes wont get stored, and no ses light. im saying, it maybe losing power for milliseconds? and start misfiring until it corrects itself. so misfire codes are common, the idea is, the ecu woke up during a misfire and detected it, but didnt record the actual sensor failure or other ses code.

next time you take it to the dealership, with the same problem, they will most likely check the ecu if they havent already. if its not the ecu, then you need the sensor logs. when there's loss of power in the charging system, it could cause the same problem, so they probably tested your battery and alternator already. a loss of voltage in the charging system could mean any voltage specific sensor could lose voltage, ie cps, tps, maf, ecu, etc.otherwise, youre going to end up chasing wires, to find a break/fray/lose wire.