Honda OLM going down while car is sitting parked

[Doog]

My daughter is studying abroad so her Civic (my Civic) has been sitting in the garage for 2 months. The OLM % number has dropped 10% in just six weeks. I only started the car once and let it run for 20 minutes and that is it. Is this normal?

 

[SLCraig]

I would assume it's normal and as long as the battery is connected it must know how much time is passing.. Also might as well just not run the car at all, idling doesn't really benefit you.

 

[Mau]

I have to start up the tl and see if it's doing it for me as well. That would be pretty darn cool then I don't have to worry about changing the oil when I pull her out some spring.

 

[Artem]

Originally Posted By: Doog

My daughter is studying abroad so her Civic (my Civic) has been sitting in the garage for 2 months. The OLM % number has dropped 10% in just six weeks. I only started the car once and let it run for 20 minutes and that is it. Is this normal?

I'm lost... it dropped from 100% in 6 weeks?! Or it was @ some other percentage?

 

[addyguy]

I'm wondering if, as many say, idling is really that hard on oil, and the OLM is reflecting that....but that would have the engine needing an OC after idling just over 3 hours!

 

[Quattro Pete]

Originally Posted By: Doog

My daughter is studying abroad so her Civic (my Civic) has been sitting in the garage for 2 months. The OLM % number has dropped 10% in just six weeks. I only started the car once and let it run for 20 minutes and that is it. Is this normal?

If that's not proof that sitting and idling to warm up the car is harmful, then I don't know what is.

 

[dparm]

Rather than just letting the car idle periodically, drive it on the highway for 10 minutes or so. That should keep the battery charged, prevent flat spots on the tires, work the suspension, and burn off any moisture in the oil. I'd rather not start the car at all than just idle it for 20 minutes. Surefire way to contaminate the oil.

 

[SteveSRT8]

Never start a stored car unless you can DRIVE it for at least 20 minutes. Idling the engine is super bad for building moisture which leads to acid formation!

 

[Dan55]

OLM is just doing its job.

 

[RF Overlord]

Originally Posted By: dparm

I'd rather not start the car at all than just idle it for 20 minutes. Surefire way to contaminate the oil.

Originally Posted By: SteveSRT8

Never start a stored car unless you can DRIVE it for at least 20 minutes. Idling the engine is super bad for building moisture which leads to acid formation!

^^^what they said^^^

 

[Garak]

Originally Posted By: SteveSRT8

Idling the engine is super bad for building moisture which leads to acid formation!

Absolutely. When my truck sits for months or years at a time, I just plug in the onboard maintenance charger. There's never a question about battery condition when I go to use it again.

 

[Tegger]

Originally Posted By: Doog

My daughter is studying abroad so her Civic (my Civic) has been sitting in the garage for 2 months. The OLM % number has dropped 10% in just six weeks. I only started the car once and let it run for 20 minutes and that is it. Is this normal?

It's normal. The OLM uses an algorithm that considers ambient temperature, number of starts, mileage driven between starts, length of time between starts, that sort of thing. Oil "gets old" even if the car is never driven, and it "gets old" even faster with lots of short trips.

 

[LckydevL]

Originally Posted By: Doog

My daughter is studying abroad so her Civic (my Civic) has been sitting in the garage for 2 months. The OLM % number has dropped 10% in just six weeks. I only started the car once and let it run for 20 minutes and that is it. Is this normal?

My Civic's OLM is graduated every 10%. I was checking it pretty regularly at about 5k when the first oil change was planned. It bounced back and forth between 30% and 40% a few times. I am guessing my Civic, like yours, was just on the edge of changing from one level to another. Unless it drops another 10%, I would not sweat it. Just keep an eye on it.