Hey fellas, just picked up another Dakota this past weekend. 91 318 4wd 140k $800. Truck is pretty sound just has one issue I need some opinions about...

I bought the truck this past Friday. Only two issues that bugged me. One is the oil pressure and coolant temp gauges do not work while the rest of the gauges do. I got a spare cluster from a buddy and swapped the coolant and oil press gauges from his to mine, still nothing. The previous owner did provide a new oil press sensor with the truck though I haven't had a chance to put it in yet. And now today, 3 days later, I started getting the oil light after 5-10 mins of starting/driving the truck. Are the oil gauge and light ran off the same sensor? Should I be worried? I have no other warning lights on.

*Update* I pulled the plug from the pressure sensor and the terminals were very corroded on both the sensor and plug, gonna try cleaning them up.

Second would be at idle the truck would start burning a bit of oil. I checked the oil the night I got it, oil was full and clean. So I decided to run some Lucas oil stabilizer. I have always had great results with that stuff in these 1st gen Dakotas. Sure enough it helped a lot! Now the truck has to sit and idle for a good while before it will start burning oil. I did read that sometimes the culprit could be the intake mani gasket?! I dont think it would be the rings or anything internal motor wise cause it's only at idle, under a load no smoke at all. Motor runs quiet and strong, nothing like my last 318 1st gen Dakota.

Any insight on those issues would be greatly appreciated. I'm gonna keep digging around the forum for any info. Thanks!

 

The oil sending unit is a common failure point. Yes replace it, if that doesn't work check your pressure with a manual gauge.

Yes the oil burning could be the Intake Plenum gasket. The lower one, but when you replace it you will need upper and lower gaskets.

 

Ok thanks for the info! Are the gauge and light linked or separate? I dont get why the light is now coming on even though the gauge hasnt worked this whole time?

What size socket/wrench do i need for the sensor?

Thanks for the heads up on the intake gaskets, im gonna start with that.

 

The gauge and the light are probably run off of two different sensors inside.

The light only comes on below a certain pressure.

 

The oil sending unit controls both light and gauge. Just replace it. I can't remember what size it is but when you buy your new one you can match it to it.

 

There is a special sensor socket for sending units and the like. It's not that expensive and it is a little deeper than the average deep socket plus it is designed to fit the sending units shape better than a 6 or 12 point standard socket. Most of the sending units out there are about the same size so it won't be a single use tool. May be worth looking into. I have one and I have used it on the Dodge truck, both my Fords and a Saturn.

 

Thanks for all the info!! Hopefully switching that sensor out fixes it!!

 

Bingo!! New Oil pressure switch fixed it!! Gauge works and shows oil pressure. Also found out why my coolant gauge wasn't working, the sensor wasn't plugged in! Things are coming along nicely. Thanks again for all the input!!

 

I'm having a similar problem after messing around with the EGR. Where exactly is the oil pressure sensor located? Is it towards the back of the engine with a 2 prong plug?

-edit-
Yes, that looks like it's it seeing as how mine is broken from the socket.

 

Yeah it's on the back of the engine up top next to the Distributer, cylinder shaped with two prong female plug. I replaced mine and still had problems with the gauge reading right so I just picked up a Sunpro Mechanical oil pressure gauge and now I have piece of mind knowing exactly what my oil pressure is doing.