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Discussion Starter #1 (Edited)
first off wierd KA hesitation, STILL!

it happens randomly but much more often when engine is at operating temperature

did some more checks today and pulled the plugs:

all of the plugs were fine but plug on clyinder number 2 was covered in oil!

not oil fouled but just thin clean oil all on the threads

apon further inspection there seems to be a bit of oil on the cylinder head

all the other plugs are okay

looking down all the other clyinders clyinder number 3 looked like a bit extra carbon ontop of the piston


but now! when I hesitate I had my friend driving behind me and he said it just smelled like unburnt fuel

the wires are good and the gap is okay but im thinking someone is causing clyinder 2 or 3 not to fire under WOT sending the smelly HC threw the cat and out the exhaust.

did a dry compression test and they all came out 165 across the board

warmed the engine up and checked exhaust color and its not black or white so its not burning coolant or running very rich.

I'm going to do a clyinder leakdown test tommorow and see how it goes but can ayone else offer any other places to look? here is the list of new or fully functioning parts:

02 sensor
engine coolant temp sensor
fuel filter (z32)
3" catco cat
NGK iridium IX plugs
NGK wires
newish cap/rotor
alternator
battery
starter (irrevilant but it was replaced)

probably a few more things but they sliped my mind.

but when my KA gets power, it roars but when it doesnt its smelly and slow.



I'm thinking now that:
the valve guide maybe worn
valve cover gasket
blowby but i would have noticed it with a comp test
plug seals ( I was told this by another tech, but I don't see anything resembling that in the FSM)
 

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Same problem here. Someone please answer.

The oil on the plug is probably a leaky sparkplug gasket, it should come in a set with the vc gasket.

I also have the same parts already replaced, lol. MAFS is up next.

What rpms does the motor hesitate at? Mine hesitates at exactly 2500rpms, and then its fine up to 4k, then on and off from 4k to redline.
 

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Discussion Starter #4 (Edited)
if it was the coil it would do it all the time to all of the clyinders.

my MAF is A-okay, puts out correct voltage. and starts to hog near 2.5k-3kish and ends near 4k-4200 or so and then it up it roars to redline, (well redline being like 6500RPM, i rarely go that high anyways heh) sometimes and I cleaned it to be sure.

and are you talking OE VC gasket? does that come with the spark plug gasket, I thought the whole thing was one piece.

ps; the nearest nissan dealership is 50 miles away in this wretched state.
 

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hoes your cap/rotor and wires. i would be checking for tiny black carbon trails leading to ground. also any connection (cap to rotor, wires to cap) need to be clean with no carbon.

i had a new cap on my SOHC for les than 4 days and the button in the middle that would connect with the rotor wasnt touching all the time. it made my car run like SHIT. i replaced with a better cap and it fixed the problem.

if you have one of those brown caps take it off and smash it on the ground as hard as you can this is the only way to fix the problem. lol it helped mine.

a cylinder balance test may help also.
 

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Discussion Starter #6
Sexual Banana said:
Same problem here. Someone please answer.

The oil on the plug is probably a leaky sparkplug gasket, it should come in a set with the vc gasket.

I also have the same parts already replaced, lol. MAFS is up next.

What rpms does the motor hesitate at? Mine hesitates at exactly 2500rpms, and then its fine up to 4k, then on and off from 4k to redline.

also do you have a symptom of a low idle?

say anywhere from 530-750?


and my cap/rotor are okay.
 
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a.) your oil is more than likely coming from a leaky valve cover gasket
b.) sounds like you have a short in one of your injector wires (which could cause it to dump MORE fuel than normal, not just shut it off. this has happened to me. in fact, this is what caused my bumper to catch fire).
 

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Discussion Starter #8
Revolution240sx said:
a.) your oil is more than likely coming from a leaky valve cover gasket
b.) sounds like you have a short in one of your injector wires (which could cause it to dump MORE fuel than normal, not just shut it off. this has happened to me. in fact, this is what caused my bumper to catch fire).
yeah but that would show a black exhaust fume saying its running incredibly rich. and you wouldnt notice the same type of power loss if it was giving it too much fuel rather than no spark at all.

I think the gasket around plug 2 is bad so im gunna try and temp fix that till I can get a new one.
 

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Discussion Starter #9
solid compression 0% clyinder leakage so valve guides aint busted

so gunna replace a worn plug and valve cover gasket

I just hope that the bolts arent a bitch on it and strip the threads, stupid aluminium :(
 
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