[GummyBears]

I recently picked up an 08 spec v sentra. The car idles roughly with noticeable misfires fairly frequently. I have replaced the spark plugs, found oil on them, and have now replaced the valve cover as well. The engine still idles poorly, with basically no improvement, and what is even more concerning to me is that two of the 4 coil packs still have traces of oil appearing on them. Is this oil possibly coming from the coil packs themselves, I understand that coil packs do have a liquid insulation of some kind? Or do I have a bigger problem?

 

[Mister_Charlie]

So I've got the same problem on my 02' Spec-V. From the google search I've done, it can be the valve cover gasket, an o-ring seal, of a few other things. Was the gasket in good condition when you changed the cover?

 

[25848]

I recently picked up an 08 spec v sentra. The car idles roughly with noticeable misfires fairly frequently. I have replaced the spark plugs, found oil on them, etc..

GUMMYBEARS
I doubt that it's the coil packs, (I started replying before I saw you have an 08) Since no one has replied, here goes.. I have an 02 Sentra, the coil packs on my 02 sit on top of the long rubber boot that extends down through the valve cover silo to cover the spark plug insulator to grip onto the terminal. I've had my 02 since 07, Never had any coil pack leak. I only had a little oil on the boot at the bottom, near the plug base was, and the oil there..
1. After pulling each plug coil, wipe them clean of oil. Examine the base all of the plug silos to see if any oil is present. Pull all of the new plugs, to see if ANY of the electrodes are being fouled again this time by the new valve cover ??
2. I found oil at the base of the insulator (right most- driver's side, plug) my 1.8L. (due to a valve cover plug gasket fail) there. Wipe off any oil residue off the insulators and also wipe the long rubber boot clean ...
3. Try to use a thin fabric towel with a long screwdriver to gently move a soft thin towel about to sop up any oil, in that area at the base. Exersize care to not damage or loosten any of those gaskets. Remember not to drop any debri into the opening where the spark plug was removed from. You don't want any objects falling into that cylinder. Try to get a 2nd look at the area cleaned by your towel. See if any gaskets are torn. Exercise care so not to damage those plug gaskets.
4. Make sure you bought the Platinum plugs, My 02 requires those, Normal non-platinum plugs may fit, but my 1.8L ran rough like it's timing was off.
5. If it were me, I would buy two, coil packs, to test with, by exchanging them with two of the existing coils to see if you can isolate hopefully one or two that may have reached the end of their useful life. If you notice improvement with the first two installed coil packs. That to me is a strong indicator to just replace the remaining two untouched coil packs. I f that does not cure it. You could purchase a Sentra repair manual for your 08 Sentra, there may be a few other inexpensive components that may be affecting the ignition performance.Lastly I bought a "Creeder" brand code reader from Harbor Freight, for the relative small expense It's a great little easy to use and very accurate code reader. I can keep it in my trunk, with my emergency gear and tools. I always carry a socket set and tire flat fix, extra bulbs etc.. Once while 60 miles from home I realized the 8.1 was quickly overheating pet the dash engine temp gauge. Then the steam emitting from under the hood. I dove into the parking of an Auto Zone or Advance Auto. Bottom Line when it cooled down I pulled the radiator and installed a new radiator, the original, suffered a crack at the filler neck from the super hot AF and pressure. Which was from a small engine head gasket leak. The gasket fail allowed hot exhause gasses to travel over to a nearby water / coolant jacket. It super heated the coolant like a blowtorch. After the install, I bought 20 gallons of water and five gal of AF, filled her up and returned home, only driving as far until the eng temp gauge began to rise above halfway, each time pulling over to let it cool down, and to refil. Once home I had it towed to a local dealer who had a very good rep and reasonable prices. The head gasket was repaired, I had NO HEAD warpage, they are aluminum, on an IRON block. SO I saved my Sentra, by having the right tools with me. Good luck.. .

 

[25848]

Mister_Charlie To rule out a worn Piston O ring, check your exhause pulse, while running the engine at idle, an worn oil ring will not wipe the cyilinder enough, and leave oil on the walls of the cylinder to be burnt on the combustion stroke. They oil vill be in the form of a hot vapor. a clean towel partially covering the exhaust exiting the tail pipe, will show evidence of fresh oil condencing onto the towell, and you should be able to smell the distinct odor of burnt oil and see a faint smokey vapor coming from the tail pipe. Likewise if you ever have a head gasket leake you will then smell a sweet vapor of aiti freeze emitting via the tail pipe. Doy your selves a favor and get a repair manual from the parts store, I also bought a $30 dollar "Creeder" brand code reader for my 02 Sentra. Saved me some good money works excellent. I keep it in my trunk with essential repair tools.

 

[Tritton]

No need to bold your replies bruh.

And you're over explaining eddk1818..

Start with the valve cover. Get a new one from Nissan, don't cheap out, the ebay ones don't fit properly and will 100% leak.

 

[GummyBears]

Thanks for your replies, by now I have replaced my valve cover and spark plugs. The engine misfiring has if anything gotten worse, and under acceleration taking it around the blocks, the engine shakes like crazy. I have two coil packs on the way, and am basically praying that the problem is just the coil packs being killed by the leaky valve cover, and not piston rings or any engine internals. This is a first project car for me, and I will, but I really don’t want to pull the engine apart. As for the b16 spec v, how hard and costly is it going to be to find piston rings, and possibly pistons? Seeing as how the engine does have different internals than most QRs.

 

[CrickiKaze]

Perform a MAF and TB relearn, as well as a fuel trim reset. Check to see if you have any soft codes.

I wonder if the knock sensor is being sensitive...

 

[25848]

..

 

[25848]

No need to bold your replies bruh.

Hey junior, I've been hot rodding since 1969, restored several vehicles frame off, just for giggles, Skylark GS 401, Buick GN, Ramcharger/Cummings to name a few. Were were you ?? I'm a retired professional and wrote more technical reports that you haven't even lived long enough to read,not to mention if you lived another 20 years.. So Mrs Manners go piss up a rope.. Focus on the message, stow the grammar crap. It doesn't accomplish the mission. Repetition facilitates long term retention, considering most people only retain about 10% what they've read. See I'm still "Bolding the text, you should have repeated yourself. While were off topic, why don' t you dump the terminator BS vibe, No one is impressed. BTW: Anyone can suggest to go buy a part.

 

[Tritton]

Tough guy. Learn how to quote.

You're right, no one is impressed how you feel the need to over explain. Again.

 

[Mister_Charlie]

I get you're trying to help but your spelling really is kinda shit at points. It also DOES make more sense to keep tips short and concise. If you've written technical reports before, wouldn't that be obvious? A big old word salad that's BOLDED isn't the most attractive thing to read, even if it's useful info someone is looking for.

 

[Tritton]

To the OP, You really need to get some codes read. Thay would at least point us in a direction.

 

[25848]

Tough guy. Learn how to quote.

You're right, no one is impressed how you feel the need to over explain. Again.

...you have no idea.. since all of you snowflakes are more concerned about grammar. Suit yourselves.
buy a shop manual. I am done with this juve crap.. good luck.

 

[CrickiKaze]

...you have no idea.. since all of you snowflakes are more concerned about grammar. Suit yourselves.
buy a shop manual. I am done with this juve crap.. good luck.

Know what an FSM is, how about the the ability to pull codes with out a scan tool, what about the niche issue of the motors that come in this chassis? If you want to pass us off because of your background that only part of your "expansive knowledge" is relevant and dumb everything down as you think we are incapable than so be it... but the only snow flake I see here is you as to regards of the post I've quoted as it seems you want us to bend to your presence.

I was going to inform you that you didn't need to "ramble" on somethings and though I didn't care about you being extra with your choice of font enhancements which is kinda annoying you seemed tolerable...

 

[Tritton]

Also, the 1.8 is an iron block, the 2.5 is not. Not thay you cared to ask the OP what motor he had in his engine, it could have been a SR20. But I digress.