Help! My 1999 Civic drinks oil…no leaks or smoke. Should I use high milage oil? Please help…
First, have the PCV system checked from end to end, not just the valve itself…The hoses, the vacuum port, everything…How many miles on the car?? How much oil does it burn?? Nothing lasts forever…There is a crankcase additive called “Restore” that MIGHT offer some benefit…
Be careful with Restore if your in a cold climate…you could blow a seal.
I took a front seal out of a toyota
Define “drinks oil”, 1 qt. every 100 miles, 500 miles, 1000 miles, etc. How many miles on the Civic? Most manufacturers consider 1 qt./1000 miles within normal consumption. If the oil is going out the tail pipe the catalytic converter will get rid of most of it until the converter fails.
A bad PCV valve can increase oil consumption, since it’s only a few dollars go ahead and replacd it.
Ed B.
How do you know it doesn’t leak? You can lose a lot of oil w/out having a puddle on the ground.
How much oil are you using? How often do you have to add in terms of mileage?
Thanks all…116000 miles…I had to add almost 3 qts after the last 3000 miles…looked for leaks on lift and there is no spotting on the ground at all…mech noted no apparent leaks while on the lift…said would use an additive if consumption continues…thank you…happy holidays to all!
No leaks means that it’s burning oil if there’s not a crankcase ventilation problem.
Oil burning is due to valve seals and/or piston rings.
Valve seals can be damaged by any overheating episodes as can the piston rings.
Piston rings can also be damaged by irregular oil changes (sludging or coking) or by running the engine chronically low on oil, which you have apparently done from the adding 3 quarts reference.
There is no test for valve seals. That’s a replace and hope option.
What should be done is a compression test, maybe twice. The first one should be a dry test and a followup wet test should be done if low compression is shown on any cylinder.
As to why your mechanic is bypassing the obvious Step One compression test I have no idea.
Three quarts in 3000 miles falls into the normal range for consumption, particularly for an aging vehicle. Hopefully you didn’t have to add all that all at once. Running an engine that low on oil can cause severe damage, the least of which will be to increase consumption of oil. The best thing to do now would be to check your oil frequently and familiarize yourself with how much oil your engine uses, and don’t let it run out! If you note consumption in excess of a quart every 1000 miles or so, it may be worth looking into some engine work to try to slow it down or stop it, the first and easiest being new valve seals and probing oil passages which lead from the head to the sump. Those are two common causes of oil consumption, and seem to be very common in Japanese cars.
“I had to add almost 3 qts after the last 3000 miles”
Does this mean that you added 1 qt after 1k miles, and another qt after 2k miles, and yet another qt after 3k miles, or does it mean that you needed to add 3 qts all at once in order to bring the dipstick up to the “full” mark? If it is the latter, your engine is doomed and no additive or high mileage oil will save it.
The idea is to never allow the dipstick to fall more than 1 qt below the full mark, simply because the smaller amount of oil, when made to do the work of a full crankcase, becomes degraded very quickly. The rate of consumption then increases geometrically, and as the oil level continues to fall, the rate of consumption and the rate of engine wear keep increasing at an increasing rate.
That Civic engine holds either 4 or 5 qts of oil, so if you allowed the oil level to fall to the point where it was 3 qts low, you essentially “cooked” the oil and “cooked” the engine. My advice (both with this car and the replacement) is to check the dipstick every few days, so that you can avoid killing another engine.
Thank you everyone…a lot to think about. Happy holidays to you all!