# shooting out black smoke (smog?)



## sentra727 (Feb 28, 2009)

well, this are the things i did before i started having this problem. i changed the valve cover gasket coz it was too old and oil was slowing oozing out. i replaced the o-ring in the distributor and replaced the cap and rotor. i had to use the same gasket that goes between the distributor and the d-cap coz i couldnt find one at the store. it put evertyhing back together. i also replaced spark plugs (ngk copper) and wires (oem) as recommended in a previous thread. the timing was done with a gun but a mech (coz i didnt know how). after all that, i noticed it was shooting out black smoke and i felt that i was losing power at high speeds. What caused the black smoke and loss of power? please help.


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## xbeaus (Oct 9, 2009)

sentra727 said:


> well, this are the things i did before i started having this problem. i changed the valve cover gasket coz it was too old and oil was slowing oozing out. i replaced the o-ring in the distributor and replaced the cap and rotor. i had to use the same gasket that goes between the distributor and the d-cap coz i couldnt find one at the store. it put evertyhing back together. i also replaced spark plugs (ngk copper) and wires (oem) as recommended in a previous thread. the timing was done with a gun but a mech (coz i didnt know how). after all that, i noticed it was shooting out black smoke and i felt that i was losing power at high speeds. What caused the black smoke and loss of power? please help.


It sounds like your timing is not correct if you have a loss of power. Maybe your distributor position? It's very critical to get all of the timing marks correct especially if it's a DOHC motor. The black smoke almost sounds like a rich condition (too much fuel) Double check the timing.


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## pulsar86 (Aug 13, 2009)

Mark the position your distributor is in now so you can find the position again if you have to. If you know the direction of the rotors rotation, loosen the clamp on the distributor turning the distributor against the direction of rotation will advance timing, with will retard. Slowly turn at idle to see if you can get your best idle and timing will be fairly close to correct.


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## RJR99SS (Aug 21, 2008)

Cant really tell if you tried this because you're ignorant and cant just type in english, but did you make sure to replace the pcv grommet in the valve cover gasket when you took it off? 

There's a little rubber seal in the front of the valve cover, right in the middle, for the pcv passage. When you take the valve cover off these fall off sometimes, or will be so old they'll just fall apart. If thats not on there the pcv will start sucking oil right out of the head and blowing smoke everywhere, especially at high rpm.


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## sentra727 (Feb 28, 2009)

well i apreciate you alls help. rjr99ss, i dont see the need of calling ppl names though . i thought we were all mature ppl in this place. if i mistyped some words then ill double check my messeges next time, instead of rushing through them before i hit the "summit post" button. anyways, pcv grommet intact.

well, i redid the timing coz i found out that the mech who did it for me, did it wrong. plus i couldnt see how he might have done it when the little mark on the crank shaft wheel was almost invisible. what i did, i cleaned the wheel and put some white-out on the 10 mark. i got the timing pretty acurately leaving a ±1 to ±2 gap. but still, that didnt do it. i still shoot out dark smoke and lose power and kinda jerks when i keep a steady speed above 45mph or when i accelerate. any other suggestions? thanks.


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## jdg (Aug 27, 2009)

sentra727 said:


> well, i redid the timing coz i found out that the mech who did it for me, did it wrong. plus i couldnt see how he might have done it when the little mark on the crank shaft wheel was almost invisible. what i did, i cleaned the wheel and put some white-out on the 10 mark. i got the timing pretty acurately leaving a ±1 to ±2 gap. but still, that didnt do it. i still shoot out dark smoke and lose power and kinda jerks when i keep a steady speed above 45mph or when i accelerate. any other suggestions? thanks.


I'll say that even though the marks are 'on', the marks might still not be 'on'...if that makes any sense. Advance the timing a bit more above what the book says you should have and see what happens. As long as you get within a few degrees of where you should be, things should run just fine. But to be sure, maybe you could pull the #1 spark plug, rotate the engine until the piston in that cylinder is at top dead center. Stick something in there, like a long thin dowel, spin the engine by hand until that 'something' goes as high as it'll go, check the timing marks on the crank pulley, they should indicate 0 degrees. This is just to make sure that everything (i.e. distributor) got installed correctly in the first place. Ya never know...
Other than that...do you have a check engine light? (never did state if you did or not)...
How much 'dark smoke' are you getting? Is it like a diesel engine that just got floored? or just a bit of a haze?
Are you sure you've got a good fuel filter in there?
Any other mods you've made that you've failed to mention so far?


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## sentra727 (Feb 28, 2009)

well, i had just a custome intake which i was told to put the stock one back on and i did. this is what i have noticed now since the begining of the problem. after readjusting the distributor (timing it), i dont have much of a problem at low speeds from what i've noticed. once i get on the freeway, and i hit high speeds like 70-80, you could feel the lack of power and you could feel it like decelerating constantly. and then, when i get off the freeway, thats when it struggles to pick up speed quick and leaves a cloud of dark smoke. not too dark but kinda like light gray more or less. also i noticed, it burned my oil so quick! i had an oil change done and after 3 days, it was gone! the oil light lit up. so i poured 3 quarts back in there right away. and no i dont get an engine light on. i was told by other sources that my fuel to fire ratio could be off coz i unplugged the distributor electrical plug whitout disconnecting the battery. could that be true? and if so, how much would they charge me to get the computer reseted?


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## sentra727 (Feb 28, 2009)

like i had said, as of now, all my engine parts are stock parts.


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## jdg (Aug 27, 2009)

sentra727 said:


> the oil light lit up. so i poured 3 quarts back in there right away.


3 qts huh...
Do you have any idea how much oil these engines hold when the oil level is at the 'full' mark?



> and no i dont get an engine light on


These engines don't have a sensor for worn rings, pistons, cylinder walls, etc.



> i was told by other sources that my fuel to fire ratio could be off


Ya, probably because you don't have any compression left.



> and if so, how much would they charge me to get the computer reseted?


Do you have a Haynes or Chilton's manual? Maybe access to the internet?


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## pulsar86 (Aug 13, 2009)

If you are getting gray smoke and using that much oil get a compression test done. You have a internal engine problem [rings or bore wear].


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## s12(20e) (Nov 21, 2007)

okay like the guy said before, if its a grayish blue to black then that means ur buring oil due to blow by cause by bad piston rings or possibily valve seals or valve guides. as mentioned before do a compression test an see if its in the range its suppose to be. as for u blowin out black smoke its either due to two things. at high rpm oil gets sucked into the intake manifold from the pcv or the breather connected to the intake hose. the other is just a valve cover gasket leak causing it to suck too much air an causing the oil from the head to seep into the block.


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## RJR99SS (Aug 21, 2008)

I'm going to have to tell you again, just to stress my point here. If this thing did NOT do this before you messed around with the valve cover, and now it's burning oil like crazy and blowing out smoke, the most likely candidate is that pcv grommet in the valve cover. When you get up in high rpm that thing will suck all the oil right out of the head and into the cylinders. 

Happened to me once, grommet just fell apart when i was driving to work. I burnt like a quart every 20 miles, left a huge grey cloud behind me. 

Now...you said you're sure it's in place, not sure how you're sure, but i'd definitely double check it, because it sounds like thats exactly whats going on here. Did you put a new one in when you changed all the valve cover gaskets? The old ones, especially if it's the original one, get old and brittle and basically just fall apart, usually if you just take the valve cover off thats enough to break them. 

One easy fix, if you dont feel like buying one, is just use a tall pile of hi temp silicone sealer in it's place. 

if it's not that, then yeah i'd guess it was worn out cylinders.


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## sentra727 (Feb 28, 2009)

ok, thanks for all your help. this is where i'm at: hadnt done a compressor check yet (not sure how much they would charge me plus i'm trying to avoid spending cash coz i'm kinda broke) i did buy however, a new fuel filter (standard fram brand), a new pcv valve, some sealant to put around the valve cover gasket and a new pcv hose that goes to the eccs (excuse the lack of proper nomenclature). as far as the gromments, well maybe i'm not too sure i understood very well about that. when i asked at the store about a pcv grommet, they told me it didnt have one. RJR, if what you mean about grommets are the little rubber rings that go on the screws of the valve cover, well i did replace those. new ones were included when i bought the gasket. as far as readjusting the distributor and rotating motor by hand to match the 0 mark at the piston's highes point, ill have to do that later since i have to ask you guys how to do that? . right now, im going to unscrew the valve cover once more, put the sealant, replace the pcv valve and hose that goes to the eccs, and the fuel filter. and ill go from there. i do have a chilton's book to help me a bit.


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## sentra727 (Feb 28, 2009)

by the way RJR, i did find the little rubber thing in the middle of the valve cover that you mention as the pvc grommet. it was hard to see but it was there alright. i wouldnt know how to ask for a new one or if they sell those things by them selves since the last time i asked about it at auto zone, they said it didint have one. maybe its called something else. i wouldnt mind replacing it since it is quite old. but its there though. ill make sure i put enough sealant on it and we'll see what happens then.


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## jdg (Aug 27, 2009)

sentra727 said:


> i wouldnt know how to ask for a new one or if they sell those things by them selves since the last time i asked about it at auto zone, they said it didint have one


The majority of those clowns/punks/rejects wouldn't know a grommet in general from a spare tire, much less what to call it. And they sure as hell won't know what you're talking about if it isn't right in front of them on the computer. Those clowns aren't trained to think. They're all (ok 99% of them) key pressing/mouse clicking monkeys making just over minimum wage. You think they care if you get your grommet or not?
If the Autozone trip fails you, just go down to one of the local hardware stores, Ace, a farm implement store, something like that. They've usually got bins and bins of nuts, bolts, washer, o-rings, springs, grommets...stuff like that.
Guys at shops like those usually know what the hell is going on. And if you can find some old goober with a load of gray hair and a beard that looks like he's been at that job and used to sell parts for Model T's, go talk to him. Those old coots know what's what. They might not know that you need a PCV grommet for a '97 Nissan Sentra GXE with a GA16DE (or whatever), but they'll likely know which bin the grommet you're looking for is in, or at least a suitable substitute.

BTW - I still say you smoked your engine when you ran it 3 quarts low...


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## sentra727 (Feb 28, 2009)

You're right jdgrotte. I will never ask anything at those auto parts stores ever again! Those bastards misled me SO BAD that it is why I had this problem. They had said that i didnt need a sealant to put on the valve cover gasket when indeed, the book says you do. And since i trusted those bastards, i skipped reading the section about replacing the valve cover gasket. I will never skip any reading again. Anyways... SUCCESS!!! Mr. RJR99SS was right! I figured what he was talking about and a simple solution got it fixed. The book says to put some sealant on certain sections of the valve cover surface and I did. Yet it didnt say anything about the pcv grommet but i also poured some sealant on that suckers opening and there, after I let it dry, VOILA! PROBLEM SOVLED!! Now my ride is smooth again, got my HP back, no more excessive oil burning, and I'm keeping my already polluted air somewhat clean again. Thanks to all who contributed to my aid. And thanks to RJR99SS for sharing his knowledge and his experience with this similar problem in the past. I learned many lessons. So for those who will be replacing the valve cover gasket on their GA16ED engines or alike, ALWAYS put some sealant around the valve cover surface AND specialy on the pcv grommet's opening surface. THANKS A LOT EVERY ONE.


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## jdg (Aug 27, 2009)

sentra727 said:


> You're right jdgrotte. I will never ask anything at those auto parts stores ever again!


Now...I didn't say that!!!  As long as you ask for a specific part for a specific application, and that exact part is right there in front of them on the monitor, you should be good to go.



> Those bastards misled me SO BAD that it is why I had this problem. They had said that i didnt need a sealant to put on the valve cover gasket when indeed, the book says you do.


And out of the factory, the GA16DE's valve cover gaskets did NOT have sealant on them. A lot of engines from the factory DON'T have sealant on gasket surfaces. Replacement gaskets, yes, of course.



> Now my ride is smooth again, got my HP back, no more excessive oil burning, and I'm keeping my already polluted air somewhat clean again.


I'd keep an eye on that oil though. If you did actually run it 3 quarts low, you're probably looking for trouble in the future. IF you can somehow, I'd suggest getting an oil pressure gauge on it and checking it out, especially at idle all warmed up, and may as well run a compression check on the cylinders while you're at it. Might tell if you hurt something when you ran it low or not. Heck...might tell if you think you might want to get rid of it sooner rather than later (i.e. you actually did hurt something that'll cost $$$$$$ in a year or two).
Glad to hear it was a cheap fix for ya though....those are the 2nd best kind....


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## sentra727 (Feb 28, 2009)

what am i looking at the oil psi to be? and where am i gonna put the gauge at? how much would i pay to run a compression check on the cylinders? right now my car's still running good. though my idle's rpm seems lower. i might have to readjust the timing again correct? how do i turn the engine by hand to position the #1 piston at its highest?


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## jdg (Aug 27, 2009)

sentra727 said:


> what am i looking at the oil psi to be?


Check the Hayes/Chilton's manual. Whatever it says. I haven't checked mine lately, I'm not worried about mine.
Off the top of my head, maybe 20-30 psi at idle, all warmed up, probably a lot more at idle with a cold engine (checking oil pressure on a cold engine is about useless by the way). At higher RPM's, maybe 40-50psi warmed up.



> and where am i gonna put the gauge at?


Put the gauge where you can see it 
Plug the other end into the hole above the oil filter where the stock oil pressure sensor goes. You'll have to get some adapters I think. Again, don't know, haven't done it myself...no need.



> how much would i pay to run a compression check on the cylinders?


Well, you can either pay a shop a crapload of $$$ or you can go out and buy a compression tester at the local parts store for probably $20 and do it yourself. Again, read the manual, and it'll explain how to do it right.



> right now my car's still running good. though my idle's rpm seems lower.


Probably all in your mind. The engine is running just that much smoother and quieter and you THINK you have fixed something major, therefore it must be idling lower. Kinda like when you replace a perfectly good set of spark plugs with a new 4 tipped platinum tipped latest/greatest thing you saw in Horsepower magazine or some B.S. like that. You think you just gained 4 seconds in the 1/4 mile and 100 more HP at the wheels. Usually it's all in your mind.



> i might have to readjust the timing again correct? how do i turn the engine by hand to position the #1 piston at its highest?


How do you turn the engine by hand to get the #1 piston at it's highest?
You turn the engine by hand until the #1 piston is at it's highest.
And at the risk of repeating myself, 'cause I'm not going to repeat myself, re-read the posts and you'll see how to find #1 TDC.


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## RJR99SS (Aug 21, 2008)

sorry i couldnt respond earlier, but yeah....i would of told not to even bother going to a fast food parts store to look for the grommet. Or seal....or whatever the heck it is...i call it a grommet, not sure if thats the techical name. See the 1.6's pcv system is fairly unique, and doesnt really fit into the auto parts stores "10 catagories fit all" type of catalog system. Seeing how most cars dont have that type of seal for the pcv, they wouldnt even think of entering it into their system. But thats how those stores work, they're ok if you know exactly what you need, and look up their inventory online beforehand and just hand them a part number, otherwise they can be pretty clueless to finding anything for you. Actually my parts guy at a dealership i worked at used to be a district manager for advance auto, he told me what i (and most others) already know, they go out of their way to hire idiots with little or no automotive knowledge or experience. That way you dont have to like...pay them well, or give them benefits, and it's no big deal to fire one, as there's tons where that came from. Just makes things easier on management, and if they screw something up they can always just throw some free oil at the customer to make up for it. 

Actually my local nissan dealer couldnt even look that part up for me, they told me it's no longer manufactured. I looked up the p/n online and came back the next day and showed them that, "oh yeah, we got a whole bin of those, i wondered what those were for". Thats parts guys sometimes....

Silicone sealer works just fine too though, you just have to make kind of a tall stack of it, like 1/4" tall so it contacts the pcv passage in the valve cover.


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## sentra727 (Feb 28, 2009)

I'll keep in mind how those auto parts stores work. The best thing to do i guess is learn your self by trial and error but better without errors . I do have an RPM guage and i do see that my RPMs at idle (all warmed up) is barely above the 750 mark. And at "D", it's just above the 500 mark. While driving, the car doesnt feel shaky but it does feel like it would stall when i come to a stop . I will definitely keep an eye on my oil consumption. I do have a feeling that i might have messed something up while running it on stressful conditions these past few days before getting it fixed. And im not kidding about how to turn the engine manualy. Im still in a learning process. I mean, what exactly do you turn or spin or move or what? I will try my best to do all these checks myself since my budget is very low these days. Not to mention im very busy currently being a single dad and working two jobs. But bare with me if it takes me repeated times to grasp something.


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## jdg (Aug 27, 2009)

sentra727 said:


> But bare with me if it takes me repeated times to grasp something.


Then you can start by grabbing the crank pulley, 'cause that's what you'll be using to turn the engine!!! Literally turn the engine by hand by grasping the crank pulley. That's about the only way I can describe it. Grab the crank pulley and turn the engine...by hand...


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## sentra727 (Feb 28, 2009)

well, yeah, i figured that. so in other words, i would have to undo the belt and then turn the pulley right? coz i have tried it with the belt on and no go . ok thanks.


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