The car: 1996 Accord LX, 4 cylinder, auto, 232,000 miles

The problem: Oil light has recently started coming on. Jiffy Lube recently changed the oil, so a junk filter is certainly a suspect. The oil level is acceptable. The light only comes on after the car has been thoroughly warmed up and the car is idling. The light sometimes flashes and sometimes stays steady. For example, two nights ago, the light flashed at a stoplight after a 25 mile interstate trip. Pulled over, turned the car off for a few minutes and restarted it, the light was steady. An hour later, the car is started again, no light. Drive home, no light until the car is idling in my garage.

This all seems like logicalbehavior if something is finally wearing out and I am losing oil pressure. What would be likely to be wearing in this engine? Oil pump? Crank, rod, or cam bearings? Where is a good place to begin troubleshooting?

 

I think that changing the oil filter would be a good place to start. A faulty oil pressure switch/connection could be the problem. The switch is ~$15 and pretty simple to replace.

You can remove the switch and put in a pressure gauge to test the actual oil pressure. My 95 manual says that an 1/8' -28 BSPT adapter is needed to attach a pressure gauge to the engine block.

 

i would HIGHLY recommend not driving a car with low oil pressure until you have this figured out. Use a good quality oil filter (like mobil 1 or K&N) and while your at it change the oil with a good oil (mobil 1, $21 at wally world)
DO NOT USE FRAM OR NAPA SILVER! they are two brands with very bad bypass valves, and that is definetly something that can cause problems with oil pressure.
Jiffy lube is notorious for not changing filters on cars. And when they do they usually use very bad quality filter.

 

The same thing is happening to me. I changed my oil filter and it didn't help. The car is fine as long as I keep the RPMs up like on the freeway. But once I slow down at a stop light or anything it comes back on and wont go off till I shut the car off for a little while. I took it to the shop this morning. I'll write later with the results. Perhaps they will be of interest.

 

I think I should stress that the light doesn't come on unless the engine is thoroughly warmed up and even then it only comes on when idling. I drove it around town a little bit yesterday without the light coming on.

I'm not much of an auto mechanic, but I am a mechanical engineer that deals with equipment maintenance on a regular basis, and the symptoms are leading me to think that something is just plain wearing out. It is worth the cost of another oil change and a pressure sender just to rule those factors out though.

 

I just got my car back from the shop. He replaced the oil pressure sensor and it seems to be working fine. (for now) Please let us know how it goes with your car.

 

well to replace internal wearing parts it is MUCH more expensive than doing some diagnostics, oil changes, etc. (upwards of $1200)

 

As an engineer you can imagine the oil pressure switch isn't a $1500 instrument that can be trusted. It's certainly worthwhile to rule out a bad switch, since they happen often enough. Unless you already own an oil pressure gauge, the cheapest way to check that out may be to replace the pressure switch.

Check the wiring, too. The oilpressure switch is SPST to ground, normally closed, circuit opens with a few psi of pressure. So a short-to-ground in the wire will set off the warning lamp.

 

get that checked otherwise if it is a failing pump, you gonna need a new engine sooner rather than later.......

 

those switches on the pre-97 models love to leak. oil is thicker when cold, so doesn't leak as readily. i feel 97.5% it's the oil pressure switch.