N14 oil pressure issue

freaky video, that would scare me too. Do you still have a mechanical gauge connected to monitor the oil pressure while it does this?

 

have you found the problem yet? I am experiencing a similar issue.

My truck is a 93 FLD120 N14. Last week I picked up the truck after getting an electrical issue resolved, was stopped at a red light about a block away and the red stop engine light turned on. Just so happened light turned green so when I accelerated the stop engine light turned off. So far the stop engine light has turned on three times in the last week in a half. Each time I have been stopped at a light, stopped traffic on freeway or waiting to make a turn. The yellow check engine light never turns on. I am not able to get any codes when using the switches on the dash.

The engine oil has been changed and level is correct, the radiator fluid level is good.

I am suspecting a bad oil pressure sensor, but looking for ideas on other possible causes.

 

I have an N14 that has over 1.6 million miles. I bought it with 480,000 miles. I have had a few oil pressure issues with it over the years.

When i first bought it, it would lose oil pressure once hot and hit 0 psi at idle. That was fixed with a set of rod and main bearings.

I have had my oil pressure suddenly drop in the mid 20's running down the road and around 5-6 psi at idle. That usually happens when a piston cooling nozzle breaks.

I had one time where it was experiencing exactly what is described in this thread. Sporadic losses of oil pressure, then oil pressure is fine. Shimming the oil pressure regulator in the pump didn't fix. Changing the pressure sensor didn't fix. Finally it quit being sporadic and went away completely. Putting a guage on it resulted in like 4 psi and that was all she would do. The problem...the oil pump has two gears inside it that pumps the oil. The one of the gears is press fit on the oil pumps shaft. This shaft started to lose grip and would just spin inside the gear and thus not pump hardly any oil. And this isn't the first time this has happened with N14's The new pumps are updated and less likely to do this.

 

I read this thread. It confirmed what I suspected.
Bad oil pressure sensor.
My oil pressure in the Freightliner dash mounted road relay, was showing gyrating pressures. 0-100 psi.
Also my yellow CEL was coming on and off. Very nervous moments. Then the red SEL flashed on/off.

Manual dash gauge showed normal oil pressures.

Changed pressure sensor, all is good.
$225.00 spendy little item.