# p0300-random misfire '02 Frontier



## billwot (Feb 6, 2011)

I'm the original owner of an '02 Frontier 4 cyl 5 spd with 130K miles on the clock. The truck has been well maintained, and had a major refresh at 75K, including all ignition components.

Friday the SES light came on. At first it would blink, then go off. It did this several times, then it came on and stayed on.

I've got it scheduled for plugs, wires, cap and rotor Monday, but I'm not otimistic. Those components only have 55K on them, and the recommended service interval is 105 K miles.

FWIW, I have been driving Nissan trucks since '87, and this is my 5th one. Never had any maintenance problems with any of the others.

Any suggestions will be appreciated.


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## azrocketman (Oct 5, 2005)

Even if the SES light is off the computer will retain the fault code in memory. Make sure you are reading all of the codes. I'll bet on an EGR problem with carbon blocking the EGR system, especially the four EGR orifices in the intake manifold (see Nissan technical bulletin NTB05-040a).

Steve


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## jdg (Aug 27, 2009)

EGR related? For a previously 'blinking' SES?
I dunno...
Usually a 'blinking SES' indicates cat damage is imminent or something along those lines...ya know...like bad...and don't drive 'cause I'm blinking...well, maybe if I get bad enough, I'll blink faster and sound a warning horn and pop a flag up from under the hood.

But, if the O/P meant blink as in 'came on for a second and went right back off'...well, then, sure, EGR temp sensor, EGR back pressure sensor, all sorts things...


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## smj999smj (Jan 1, 2006)

Bottom line is you should get the trouble codes retrieved before replacing anything. You're probably wasting money on the tune-up parts.


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## billwot (Feb 6, 2011)

Thanks for the tips. 

I have pulled the codes (the good ol' boys where I get my OBDII inspection pulled the codes.) P0300 was the only code displayed. And it initially came on blinking (maybe 30 seconds), then would turn off, then come back on blinking. After about 3 of those cycles, it came on and stayed on.

And yeah, I realize the tune-up parts are probably not going to solve it, but it seemed like a good place to start.

Where can I find I find that Nissan tech bulletin?

bill


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## jdg (Aug 27, 2009)

Crank position sensor?
Does this thing have cam position sensors?
I don't own one of these, so I'm just throwing ideas out there to see what sticks (or stinks for that matter...).
When the light came on, how crappy did it start running? Is it running fine now? Does it start ok cold in the morning?

(And that EGR thing from above...ok...makes sense...)


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## billwot (Feb 6, 2011)

It starts fine, warm or cold. It idles fine, but you can definitely feel it miss when driving.

bill


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## azrocketman (Oct 5, 2005)

billwot said:


> Thanks for the tips.
> 
> I have pulled the codes (the good ol' boys where I get my OBDII inspection pulled the codes.) P0300 was the only code displayed. And it initially came on blinking (maybe 30 seconds), then would turn off, then come back on blinking. After about 3 of those cycles, it came on and stayed on.
> 
> ...


Nissanhelp.com | All About Nissan

Steve


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## azrocketman (Oct 5, 2005)

jdgrotte said:


> EGR related? For a previously 'blinking' SES?
> I dunno...
> Usually a 'blinking SES' indicates cat damage is imminent or something along those lines...ya know...like bad...and don't drive 'cause I'm blinking...well, maybe if I get bad enough, I'll blink faster and sound a warning horn and pop a flag up from under the hood.
> 
> But, if the O/P meant blink as in 'came on for a second and went right back off'...well, then, sure, EGR temp sensor, EGR back pressure sensor, all sorts things...


The blinking SES indicates a significant miss. Yes, continuing to operate the vehicle can cause converter damage. The original poster's comments did not indicate that the SES stayed on for long periods of time.

I'm speaking from personal experience and responses to similar issues with KA24 equipped Frontiers. I'd suggest that you cut the nonsense and look at the TSBs yourself (especially if you do not own one of these trucks and appear to have no clue about their technical features).

Steve


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## billwot (Feb 6, 2011)

azrocketman said:


> Nissanhelp.com | All About Nissan
> 
> Steve


Thanks!

bill


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## jdg (Aug 27, 2009)

azrocketman said:


> I'd suggest that you cut the nonsense and look at the TSBs yourself (especially if you do not own one of these trucks and appear to have no clue about their technical features).
> Steve


Whoa...whoa...whoa...hey, hold on there Sparky...just trying to be a bit of a help in a generic sense...which, you have to admit, is a HELL of a lot more help than the overwhelming vast majority of the general population can give over a lifetime of trying.
And as far this 'nonsense' goes...where? Find me one bit of this so-called 'non-sense' you are eluding to.


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## azrocketman (Oct 5, 2005)

jdgrotte said:


> Whoa...whoa...whoa...hey, hold on there Sparky...just trying to be a bit of a help in a generic sense...which, you have to admit, is a HELL of a lot more help than the overwhelming vast majority of the general population can give over a lifetime of trying.
> And as far this 'nonsense' goes...where? Find me one bit of this so-called 'non-sense' you are eluding to.


"non-sense" follows:

"Crank position sensor?
Does this thing have cam position sensors?
I don't own one of these, so I'm just throwing ideas out there to see what sticks (or stinks for that matter...)."

The KA24 has a distributor, you know, that round thingy with a cap and wires coming out of it. Does not need a camshaft position sensor or a crankshaft position sensor because a distributer is mechanically engaged with the camshaft and crankshaft via gears and chains. And no, gears and chains in this example are not some form of freaky sex. You may not own one, but if you are going to offer advice you should have the courtesy to look under the hood of one. 

Steve


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## jdg (Aug 27, 2009)

azrocketman said:


> The KA24 has a distributor, you know, that round thingy with a cap and wires coming out of it. Does not need a camshaft position sensor or a crankshaft position sensor because a distributer is mechanically engaged with the camshaft and crankshaft via gears and chains.


Well, as you may or may not know, a lot, as in majority, of vehicles of the '02 and up variety are DISTRIBUTOR-*LESS* and use cam and crank sensors.



> You may not own one, but if you are going to offer advice you should have the courtesy to look under the hood of one.


At least I've got the common courtesy to offer any advice at all.

Now here's some advice for you, and it's advice I use often:
Step outside, put one hand in your left pocket and play a one-handed game of hide and go [email protected]%k yourself...
WTF? Did you wake up this month and have a glass of Carnation Instant Prick or what?


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## billwot (Feb 6, 2011)

Yes, my '02 has a distributor.

Well, my local service garage replaced the rotor, cap wires, plugs, fuel filter, air filter, and Seafoamed it (personally, I think Seafoam is snake oil...) total cost $202.

And I'm pleasantly surprised to find the SES light is no longer lit. I'm still not convinced the problem is gone. I'll drive it a few days and see what happens. But I think the time has come start shopping. And even though I've been drving these Nissan trucks almost 25 years, the next one might be a Toyota Tacoma.


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## jdg (Aug 27, 2009)

Seafoam - Some swear by it, some swear at it (I swear at it personally, but don't doubt it has worked for some people).
A full tune-up like that after 55K miles is a bit on the low mileage side, but too many variables to be sure of how long anything is going to last these days (weather, driving conditions, operator methods, and so on). 

I don't think you can go wrong either way...Nissan or Toyota...
Keep the old truck...Keep all that money in your pocket...You know the truck, you know it's personality and all that...but ya almost never know what might conk out next.
Buy the new truck...Get a brand new vehicle with that new vehicle smell...Good warranty service...relatively sure that something random won't 'conk out next'...but you're still out all that money.
Can't win either way...but ya can't lose either way...


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## smj999smj (Jan 1, 2006)

Well, actually it does have a crank position sensor, inside of the distributor.


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## billwot (Feb 6, 2011)

I downloaded the Section from the service manual that covers codes 0300-0304. It specifically references the "Crankcase position sensor". It also states _"If the engine speed fluctuates enough to cause the CPK sensor signal to vary, the ECM can determine that a misfire is occurring."_

And since one of the possible causes listed is "Drive plate/Flywheel". I would guess that the CPK sensor reads crank position at the flywheel.

bill


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## billwot (Feb 6, 2011)

jdgrotte said:


> I don't think you can go wrong either way...Nissan or Toyota...
> Keep the old truck...Keep all that money in your pocket...You know the truck, you know it's personality and all that...but ya almost never know what might conk out next.
> 9Buy the new truck...Get a brand new vehicle with that new vehicle smell...Good warranty service...relatively sure that something random won't 'conk out next'...but you're still out all that money.
> Can't win either way...but ya can't lose either way...


I was only planning to keep it another year anyway. So if I get a new one now, its not a big change in plans.

And I've reached the age (69) that reliability is my top priority. Also, my wife sometimes drives my truck, so that makes reliabilty even more important.


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## jdg (Aug 27, 2009)

billwot said:


> I downloaded the Section from the service manual that covers codes 0300-0304. It specifically references the "Crankcase position sensor". It also states _"If the engine speed fluctuates enough to cause the CPK sensor signal to vary, the ECM can determine that a misfire is occurring."_
> 
> And since one of the possible causes listed is "Drive plate/Flywheel". I would guess that the CPK sensor reads crank position at the flywheel.
> 
> bill


Not only if the engine speed fluctuates, but if the sensor itself is goofy, has some metallic 'fuzz' on it, maybe if it's not seated all the way, and so on, anything to mess with that signal coming out of it, the ECM could interpret that as a misfire, even if the engine isn't mis-firing. Same thing goes with messed up/chipped/worn teeth on the flywheel. Teeth get worn down, distance to the actual crank sensor increases a hair, same thing ends up happening.

It's the same old story with different parts.
Back in the day you had bouncing points. Now we've got sensors that are touchy.
If it ain't one thing it's another...


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## azrocketman (Oct 5, 2005)

jdgrotte said:


> Well, as you may or may not know, a lot, as in majority, of vehicles of the '02 and up variety are DISTRIBUTOR-*LESS* and use cam and crank sensors.
> 
> 
> At least I've got the common courtesy to offer any advice at all.
> ...


Yes, I'm aware that many vehicles today use camshaft and crankshaft sensors in lieu of a distributor. In fact, my 1997 Saturn and 1995 Windstar do not have distributors.

I enjoy engaging in a battle of wits periodically. It appears that your sole and often used (in your own words) defense is crudity. It is not becoming of you nor is it appropriate for this forum.

Steve


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## azrocketman (Oct 5, 2005)

It could be said that all distributors sense crankshaft position. In a points style distributor the distributor is typically driven by the camshaft to have the proper rotational speed (1/2 crankshaft rotating speed). The camshaft is driven by the crankshaft so, indirectly the lobes on the distributor cam represent crankshaft positions. Newer vehicles that use points less distributors use some form of multiposition indicator, e.g. magnetic reluctor wheel, beam interrupter, in lieu of a distributor cam lobe to trigger the ignition pulses. Again, indirectly these indicators are crankshaft position sensors. Vehicles without distributors will typically mount the sensing system physically at the crankshaft to determine position. 

Steve


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## jdg (Aug 27, 2009)

azrocketman said:


> It appears that your sole and often used (in your own words) defense is crudity. It is not becoming of you nor is it appropriate for this forum.


Whatever works...


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## jdg (Aug 27, 2009)

azrocketman said:


> It could be said that all distributors sense crankshaft position....................................
> Vehicles without distributors will typically mount the sensing system physically at the crankshaft to determine position.


Looking forward to when they start using LVDT's to determine actual piston position vs. crankshaft position, then the manufacturers get that whole 'static start' thing working reliably, all way down the road of course.


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## smj999smj (Jan 1, 2006)

I'm waiting for them to come up with electronic valve solenoids to completely replace the valve train... Imagine the flexibility in valve timing and the power gains due to loss of engine friction caused by cams and timing chains, etc., plus the weight reduction!


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## smj999smj (Jan 1, 2006)

"Camshaft position sensor" is inside distributor; "crankshaft position sensor" is on the left,top side of the trans bellhousing, covered with a metal heat shield and held in with a 10mm head bolt...and a pita to get to!


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## jdg (Aug 27, 2009)

smj999smj said:


> I'm waiting for them to come up with electronic valve solenoids to completely replace the valve train... Imagine the flexibility in valve timing and the power gains due to loss of engine friction caused by cams and timing chains, etc., plus the weight reduction!


I read about Mercedes or Volvo or somebody like that trying it off and on over the years. So far, it doesn't work well for reliability reasons. But once that's all sorted out...WOW! It'll be nuts... I would think almost as much, if not more, of a leap in power and fuel mileage as what direct injection did vs. MPFI.


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## smj999smj (Jan 1, 2006)

Similar in principal to a fuel injector, but yes, would need to be much more robust and should be serviceable from the top of the head. This would also elminate the need to lubricate the cylinder head. EGR valves elimated as they have been in some variable timing engines, as this can be done with the timing of the intake and exhaust valve solenoids. Non-interferance engine design would be a must. Got a lot of potential if they can figure out how to do it and make it reliable!


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