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Since last oil change my car has been consuming a lot more than usual, so I had to change it with just 3500-4000 km (not miles) on it because level getting too low (close to the L mark on the dipstick).
Car background:
http://www.ericthecarguy.com/forum/topics.aspx?ID=1259
(I should note that we changed NGK BKR5E
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Is this the car in your avatar? Do you race it? I’m not sure how much help I can offer if so. It looks like the plus is getting too much fuel. Maybe try moving the fuel injector to a different cylinder. This doesn’t explain the compression issue, but maybe the carbon on the plug. Oil burns will give you a white crusty build-up. The top plug looks almost fouled.
Edit: It’s been awhile since I ‘read’ spark plugs, so you might disregard my post. I did find this handy tid-bit though.
http://www.ngksparkplugs.com/tech_suppo … aqread.asp.
By the looks of the plugs. Your oil fouled. Do a leak down test.C8-)
http://www.youtube.com/watch?v=WgrfT0LF … plpp_video leak down test
Quoted From Beefy:
Is this the car in your avatar? Do you race it? I’m not sure how much help I can offer if so. It looks like the plus is getting too much fuel. Maybe try moving the fuel injector to a different cylinder. This doesn’t explain the compression issue, but maybe the carbon on the plug. Oil burns will give you a white crusty build-up. The top plug looks almost fouled.
Edit: It’s been awhile since I ‘read’ spark plugs, so you might disregard my post. I did find this handy tid-bit though.
http://www.ngksparkplugs.com/tech_suppo … aqread.asp.
Nope, not the car in my avatar, look at the link I posted to see the actual car 😉
The pictures are not my actual spark plugs and I got them from the denso website (almost the same as the NGK link you posted)
Thanks for your reply
Quoted From college man:
By the looks of the plugs. Your oil fouled. Do a leak down test.C8-)
http://www.youtube.com/watch?v=WgrfT0LF … plpp_video leak down test
Those are not my actual plugs, posted them as a reference. I’m not sure if a leak down test would be of any help since my problem is an excess of compression, not a combustion leak.
Thanks for your reply
I try to stay away from cars that have been modified but, can you check your valve adjustment. If those valves are staying closed to long it could cause this. At least in the exhaust side. I only say this in theory cause I never personally seen it. And I never had to work on a Nissan yet.
Are those compression numbers from a dry or wet test? If the readings increase on a wet test, usually its a sign on ring wear.
For the valve guide seals, if you see some blue smoke on deceleration (have someone follow you), thats usually a sign of worn valve guide seals.
Is your PCV system working correctly?
Honestly I don’t think the 195 is high so much as the rest are a little low and not an uncommon thing in my experience, usually the cylinder with the least wear is closest to the coolant inlet coming from the radiator, it stays cooler longer and more consistently. That said you say it got worse after you changed the oil, you wouldn’t have happened to change it with synthetic oil would you? If so this could be the cause of increased oil consumption. If you’re running regular oil your engine is probably getting worn and burning more oil, in my experience it’s not any one thing that normally causes increased oil consumption when it comes to engine wear it seems to occur evenly and throughout the engine so just going in and changing the valve seals or piston rings isn’t necessarily going to cut it you normally have to do a full rebuild with the proper machining and measuring OR replace it with a used or rebuilt unit (I consider this option the most practical and to have the best chances of success). Lastly if you do a lot of sustained high speed driving like 70-80mph on the highway for long periods this will increase cylinder pressure and cause increased oil consumption on ANY engine not just an older worn out one.
Quoted From EricTheCarGuy:
Honestly I don’t think the 195 is high so much as the rest are a little low and not an uncommon thing in my experience, usually the cylinder with the least wear is closest to the coolant inlet coming from the radiator, it stays cooler longer and more consistently. That said you say it got worse after you changed the oil, you wouldn’t have happened to change it with synthetic oil would you? If so this could be the cause of increased oil consumption. If you’re running regular oil your engine is probably getting worn and burning more oil, in my experience it’s not any one thing that normally causes increased oil consumption when it comes to engine wear it seems to occur evenly and throughout the engine so just going in and changing the valve seals or piston rings isn’t necessarily going to cut it you normally have to do a full rebuild with the proper machining and measuring OR replace it with a used or rebuilt unit (I consider this option the most practical and to have the best chances of success). Lastly if you do a lot of sustained high speed driving like 70-80mph on the highway for long periods this will increase cylinder pressure and cause increased oil consumption on ANY engine not just an older worn out one.
Hi Eric, I’ve used syntetic oil since I bought the car.
Is it possible that oil is getting inside the cylinder trough the piston rings due to an oil ring being out of place? (like it lightly rotated)?
Quoted From Heath Knox:
I try to stay away from cars that have been modified but, can you check your valve adjustment. If those valves are staying closed to long it could cause this. At least in the exhaust side. I only say this in theory cause I never personally seen it. And I never had to work on a Nissan yet.
Would seem weird to me that it’s just one cylinder that’s causing the problem if that was the case.
Quoted From dreamer2355:
Are those compression numbers from a dry or wet test? If the readings increase on a wet test, usually its a sign on ring wear.
For the valve guide seals, if you see some blue smoke on deceleration (have someone follow you), thats usually a sign of worn valve guide seals.
Is your PCV system working correctly?
Dry test, I wouldn’t think my rings are worn out as the reading has excess pressure, not lack of.
As I asked Eric, I think maybe one of the oil rings rotated slightly causing oil to end up in the cylinder.
About the PCV, I think it’s working fine, and if it was the cause my throttle body would be choked with oil all over, not the case. I’ll probably eliminate it next week along with bypassing the throttle body heating system.
That’s not how it works really, keep in mind the cylinder walls wear as well as the piston rings, the simplest way I can explain it is the hole the piston is in gets worn and bigger than it was when it started, this can create leakage as a result of loose parts and it will burn more oil as a result. As I mentioned before if you’re running synthetic oil I would suggest switching to regular oil as it may not burn as easily as synthetic oil will.
Thanks Eric!
I’m going to get new camshaft (SR16VE N1, which is plug and play), new pistons and rings so I can make better use of the engine opening.
I’ll get back to you guys when I somehow fill my empty pockets LOL
Thanks!
Quoted From EricTheCarGuy:
Don’t forget to have the cylinders bored and honed or you may be wasting your time, at the very least you need to measure them to make sure they’re in spec. If you have to bore out the engine you’re going to have to get new larger pistons as well.
+1!!
You may also need a ridge reamer. If you dont have the tools to do all these precise measurements, its usually best left to a machine shop.
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