Oil pressure problem???? - Diesel Forum

LunaTech · 07-26-2008, 06:56 PM

Ok, first my truck is a 1994 F350, 7.3L IDI with the factory turbo. I just changed the oil (Rotella T 15w40) today, started and let the oil circulate and shut it down to check the level, everything is fine. The problem is with the oil "pressure gauge" in the truck. As I was driving and the RPM's went up the oil gauge would drop. At idle it showed at the "r" in normal but at about 3000 it would show at the "N" in normal. There is no unusual noise coming from the engine, but I was wondering if anyone has run across this before. I did do a search but could not find anything on this but did run across this link ( TheDieselStop.Com - www.thedieselstop.com ) in a post which I plan on doing but I want to make sure there is nothing I need to check before I can get this done. I don't want to damage the engine. Any help would be great.

Jeff

Kaliburz · 07-26-2008, 07:47 PM

If you are concerned on oil pressure, you can always connect a manual guage and see what the actual presure is to ease your mind. You dn't have to install in perm., but just as a check....

LunaTech · 07-27-2008, 08:50 AM

Any other comments or ideas?

LMJD · 07-27-2008, 09:21 AM

Only comment is I agree with Kaliburz, these electrical oil gauges fluctuate, due to design it's pretty rare for an oil pump or pressure relief valve to fail in a diesel engine.

Snotzalot · 07-27-2008, 11:40 AM

The F series usually had a on/off sender only and not a true gauge. Check the connector on the wiring to the sending unit, that could be dirty or bad. Give it a wiggle to see if that helps. The E series had an actual gauge.

LunaTech · 07-28-2008, 05:28 PM

Thanks for the input everyone. The connector on the pressure switch was dirty. Cleaned it and the problem cleared up. Thanks again.

Jeff