Hey I rebuilt my b18. Shortly before getting it rebuilt, the oil light was turning on but not fully, just a little bit. I replaced the oil pump and everything works fine, but 3 works after, the oil light is on again in the same way. I can see it on only at night. Do you think is the oil pressure switch that needs to be replaced or the oil pump failed? I must say that my car is at 750 rpm when idling and it doesn't shake

 

if you replaced the pump with a new OEM Honda one I'd say the switch.

 

No, it was used. We checked it and it was ok. I've read that if the oil is so thin, when the engine warmps up, the oil becomes even thinner and that would make the pressure go lower, because the light in my cluster is barely noticeable. Is that true? Idk how much a new oil pump costs

 

what type of oil are you using ? new ones are about 130

 

I used chevron 20w-50 but it was very liquid.

 

Shouldn't you run 5w-30 in Hondas? That's what it says on my oil cap and and my manual? 20w-50 is pretty thick isn't it.

 

The oil pressure switch is an on/off switch, there is no inbetween, [unless defective] it is on, [pressure is above limit] or off, [pressure is below limit].

The pressure switch supplies a ground, [when pressure is up] to the oil pressure warning light, the ign. supplies the power to the bulb, to test switch, unplug it, start engine, if light is out the switch is the problem, replace it, if the light is still on, the problem is wiring, the lead running from the switch to the oil light is shorting out, [minor short], if the light is bright when you turn on the ign. switch the oil light circuit is good, [other then a possible minor short]. 94

 

ever check your oil pressure or just decided to change the oil pump