Running too rich and burning oil

Spyro

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What's up guys, my car is burning oil, about a quart a week or 300 miles and I daily drive my car. When I drive at a higher RPM (not hitting Vtec) like going up a hill or something, it starts to blow black smoke out from the tailpipe which usually signifies I'm running rich. The oil burning is probably due to an overly rich condition which I can understand, but I tried a number of things already to try and fix it and still no change. When starting the car on a cold start it spits out soot onto the garage door, but doesn't quite "smoke up" like it does at higher RPM's, it's fairly clear like it's supposed to be. I don't want to start throwing random parts it doesn't need.

The engine is a D16y8 with currently 109k original miles, automatic trans, car is stock for the most part. The only modification is a cold air intake, headers, and recently got a test pipe and cat back exhaust because the cat died (but it's been running rich before any of the exhaust was modified).

My timing is correct, it's spot on and where it's supposed to be, my distributor is still original, I used a timing light to check ignition timing and it's spot on, checked fuel injectors resistance all at around 12 ohms, I always use NGK plugs and wires, the spark plugs look black, but not wet, more like dried carbon, oil change done every 3,000 miles with 5w-30,

Some of the things I've done to it at 100k include a new fuel filter, new air filter, new pcv, new valve cover gasket, new headgasket (as soon as it started to seep/leak), new power steering pump (started to leak), new radiator (original started to leak), new rack (play in steering), new oil pump (leaking), new front and rear main seals (due to leakage), timing belt and water pump and distributor o-ring at 80k.

All and any help is greatly appreciated, and yes I know I'm saving a single cam lol, but it's my only ride until I can get my swap plus it's still a baby for 109,000 miles
 

HeX

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Did you also replace the spark plug cylinder seals when you replaced the valve cover gasket? Check the spark plug gaps. Are you only using 87 octane?
 


Spyro

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Yeah I replaced all the seals on the valve cover, cylinder seals, bolt seals and I'm running 89 octane. The car used to run on full synthetic 5w-30 and 91 octane which I know doesn't belong in the car, so reverted to 89 and regular oil. Isn't 87 too low though? And the spark plug gaps are at .044 but I checked that before I installed them.

The car is completely leak free from the outside, no residue or visible leaks.
 

Diana Nam

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could be valve guide stem seals going bad, assuming when you checked your plugs it wasn't wet with oil
 


Spyro

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Yeah nothings wet, and believe it or not I ordered all the valve stem seals, and new intake and exhaust valves, but I'm trying to make sure it's that before I take the head off again and end up with the same issue. When I took the head off a while back cylinder four had some heavy carbon deposits...
 

Diana Nam

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well then looks like its about time you put those new stem seals in at this point i would also check the valve stems to make sure they're good too.

not as hard to do after you have the valves out, replaced my when i was building my H22a head with all new supertech valvetrain
 
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Spyro

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Yeah, just the time factor lol. I'd have to wait til the summer comes back when i get the other car on the road again
 

dancam

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Valve stem seals went on a car of mine, burned a litre every 300km and shot oil 4ft out the tailpipe when started in the cold but plugs weren't wet. This sounds like a very leaky car... :p


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mc360

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Yeah nothings wet, and believe it or not I ordered all the valve stem seals, and new intake and exhaust valves, but I'm trying to make sure it's that before I take the head off again and end up with the same issue. When I took the head off a while back cylinder four had some heavy carbon deposits...
Little trick, you can pull the spark plug hole and run some thin nylon rope down into the cylinder (leave enough hanging out to pull it back out) then turn the crank by hand to pin the valves closed so you can swap the valve guide seals without removing the head.
 

HeX

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In regards to the fuel and running rich, those engines are designed to ignite only hot enough to fully burn regular 87 octane. The higher the octane the higher the temperature it needs to be fully burned. Thus, running higher octane in this engine has allowed for unburned fuel to sit and gunk up your internals and components. Therefore, you need to switch to a quality brand 87 octane immediately. Theres a good chance youll notice an improvement shortly thereafter once the computer readjusts to running on what its designed to burn. If this car's been errantly ran with 91 then 89 for an extended period of time, you should also run some quality fuel system cleaner, such as SeaFoam or Techron. SeaFoam top engine cleaner is another great option to consider along with a fuel additive.
 

Joe Mason

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I'd lean to valve stem seals too. It's possible to replace them without removing the head as mentioned above. However, if you can get a decent second hand head and clean/prep it with new seals and possibly valves for a reasonable price you may want to consider that route. It's pretty inexpensive to have valves seated at a machine shop and you'd have some serious peace of mind with new/clean parts. Good luck! Keep us posted!
 

nd4sped

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Go rent a leak down tester from Oreilly auto parts. You will need an air compressor to do this test but you will be able to find your oil leak but doing this test properly.
 


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