Bear with me, this is going to be kind of long…
My car has been a bit of an oil burner since new, but the amount has gone up enough that it's starting to seriously annoy me. I don't have detailed notes on the consumption levels for every fill, but what notes I do have show that it has trended upward. What I don't know for sure is at what rate or how regularly it's trended upward. I've tried to include whatever details I think are pertinent. My overall question here is, what should I do about it?
The car is a 2007 Civic 1.8 with manual trans and 64k miles. I bought it new in January of 2007 and noted some consumption starting with the factory fill. I've run the recommended 5w-20 dino for its whole life. ~6000 mile OCIs per the OLM. UOAs have come back fine. I drive spiritedly much of the time but I do not abuse it or drive it hard when cold. My commute is ~12 miles each way and includes a big hill so it does get high load at medium engine speed (~3500 RPM) on the way up and high vacuum on the way down every day.
At this point it appears to be consuming about a quart every 2000 miles. The sump is only 3.9 quarts so this isn't great. Obviously I can keep on top of it but it's still annoying. I first noted this rate of consumption with Chevron Supreme for two fills. On the second fill of CS I was topping off with Valvoline, which I'm running right now, and the same level seems to be continuing.
I've run the following oils: Exxon Superflo, Motorcraft, Pennzoil, Castol GTX, Chevron Supreme, Valvoline. I've seen the lowest consumption I think with either the Superflo or the Motorcraft and the highest with the CS and possibly the Valvoline (don't know for sure yet). The obvious observation here is that the lowest consumption was also earlier in the car's life so it could be trending upward regardless of the oil brand.
I considered taking it to the dealership before it was out of warranty but didn't for two reasons. First, dealerships tend not to care about oil consumption unless it's more than 1 quart per 1000 miles. Second, I was lazy about it. I was kind of intending to start using synthetic oils after the warranty was up and run them for ~12k (2 OLM cycles) but if this keeps up, I'm not going to be topping off with expensive oil so I'll just keep up dino at 5-6k.
So, that's the history, here's what I've tried to do:
1) I've looked for leaks and haven't found any. There's some road grime on the side of the block facing the front of the car that I suppose could be sticking due to leaking oil but it's not enough that it could be attributed to 2-3 quarts of oil per OCI. I also noticed a little bit of oil under the flywheel inspection cover a few thousand miles ago (seepage from the rear main seal) but also not enough to account for the consumption I don't think. I've never seen a puddle on the ground, nor any hint of oil accumulating on the bottom of the engine. I'd think this much oil over 60k miles would be noticeable if it were leaking.
2) I replaced the PCV valve a while ago. The original one was not stuck or anything, and there doesn't seem to have been a change in consumption. The hose going from the valve to the manifold had a little bit of oil residue in it (normal, right?) but was not clogged or anything.
3) I did a compression test earlier this week and got a solid and even ~200 PSI across the board. I realize this doesn't mean the oil control rings are OK but the engine doesn't seem to be prematurely worn or anything. Power is fine and it runs smooth enough (there's always been slight vibration at idle that I think may be motor mount related).
4) The spark plugs aren't oily.
So my question is what's next? I'm thinking next OCI I'll go back to Motorcraft, which had the lowest consumption I've kept track of so far, and see if that makes a difference. Is there anything I should be looking for beyond what I described above? Is it worth trying a synthetic to see if it burns less? Should I try moving up to a 5w-30?
I've mentioned this before in other threads but I wanted to write down everything to date in one spot and see if there's anything obvious I've missed or if I should just give up on it. This isn't a huge problem practically, but it grates on me.
My car has been a bit of an oil burner since new, but the amount has gone up enough that it's starting to seriously annoy me. I don't have detailed notes on the consumption levels for every fill, but what notes I do have show that it has trended upward. What I don't know for sure is at what rate or how regularly it's trended upward. I've tried to include whatever details I think are pertinent. My overall question here is, what should I do about it?
The car is a 2007 Civic 1.8 with manual trans and 64k miles. I bought it new in January of 2007 and noted some consumption starting with the factory fill. I've run the recommended 5w-20 dino for its whole life. ~6000 mile OCIs per the OLM. UOAs have come back fine. I drive spiritedly much of the time but I do not abuse it or drive it hard when cold. My commute is ~12 miles each way and includes a big hill so it does get high load at medium engine speed (~3500 RPM) on the way up and high vacuum on the way down every day.
At this point it appears to be consuming about a quart every 2000 miles. The sump is only 3.9 quarts so this isn't great. Obviously I can keep on top of it but it's still annoying. I first noted this rate of consumption with Chevron Supreme for two fills. On the second fill of CS I was topping off with Valvoline, which I'm running right now, and the same level seems to be continuing.
I've run the following oils: Exxon Superflo, Motorcraft, Pennzoil, Castol GTX, Chevron Supreme, Valvoline. I've seen the lowest consumption I think with either the Superflo or the Motorcraft and the highest with the CS and possibly the Valvoline (don't know for sure yet). The obvious observation here is that the lowest consumption was also earlier in the car's life so it could be trending upward regardless of the oil brand.
I considered taking it to the dealership before it was out of warranty but didn't for two reasons. First, dealerships tend not to care about oil consumption unless it's more than 1 quart per 1000 miles. Second, I was lazy about it. I was kind of intending to start using synthetic oils after the warranty was up and run them for ~12k (2 OLM cycles) but if this keeps up, I'm not going to be topping off with expensive oil so I'll just keep up dino at 5-6k.
So, that's the history, here's what I've tried to do:
1) I've looked for leaks and haven't found any. There's some road grime on the side of the block facing the front of the car that I suppose could be sticking due to leaking oil but it's not enough that it could be attributed to 2-3 quarts of oil per OCI. I also noticed a little bit of oil under the flywheel inspection cover a few thousand miles ago (seepage from the rear main seal) but also not enough to account for the consumption I don't think. I've never seen a puddle on the ground, nor any hint of oil accumulating on the bottom of the engine. I'd think this much oil over 60k miles would be noticeable if it were leaking.
2) I replaced the PCV valve a while ago. The original one was not stuck or anything, and there doesn't seem to have been a change in consumption. The hose going from the valve to the manifold had a little bit of oil residue in it (normal, right?) but was not clogged or anything.
3) I did a compression test earlier this week and got a solid and even ~200 PSI across the board. I realize this doesn't mean the oil control rings are OK but the engine doesn't seem to be prematurely worn or anything. Power is fine and it runs smooth enough (there's always been slight vibration at idle that I think may be motor mount related).
4) The spark plugs aren't oily.
So my question is what's next? I'm thinking next OCI I'll go back to Motorcraft, which had the lowest consumption I've kept track of so far, and see if that makes a difference. Is there anything I should be looking for beyond what I described above? Is it worth trying a synthetic to see if it burns less? Should I try moving up to a 5w-30?
I've mentioned this before in other threads but I wanted to write down everything to date in one spot and see if there's anything obvious I've missed or if I should just give up on it. This isn't a huge problem practically, but it grates on me.
