PDA

View Full Version : Oil pressure & underheating problems? 4d55



coyotefiveoh
08-18-2014, 04:58 PM
First off, what should my oil pressure read normally on a 4d55 engine out of a 1986 ford ranger? My check engine oil light has come on, and its full of oil, so i may be getting low oil pressure.... :( Going to double check the sending unit is all connected tonight.


Second off, the gauge where my tack is does not seem to be going up as high as it used too... (temp gauge) does not seem like it is reaching proper operating temp....(i know i should have a better gauge but i have not got one yet)

The needle used to go almost half way up, now it is barely coming to the first tick. I know the thermostat is not stuck open because it has never had one since i bought the truck. Any ideas? I should probably get a better gauge and double check the reading to verify if it is not getting up to proper operating temp and go from there just to rule out a shitty gauge....

Hopefully these problems are not related....

royster
08-18-2014, 08:37 PM
I know the thermostat is not stuck open because it has never had one since i bought the truck.

There's your under-heating problem.

coyotefiveoh
08-19-2014, 11:40 AM
yes i realize that.... but before the summer started. It would always get up to proper operating temp.... i re-crimped the line going to the sending unit and it seems to be reading higher like it used too now.

Re: the oil pressure sensor, the sensor seems like it is connected. so hopefully its not the pressure, ill have to get a gauge hooked up and go from there.


I also found a mysterious wire that looks like it would go onto the oil sending unit or something like that, but i cannot figure out where the heck it goes, i will upload a picture of it shortly and hopefully someone will know! :)

coyotefiveoh
08-19-2014, 12:35 PM
Here is a pic of what i found... any idea where this goes? Found on passenger side, along the frame rail, cannot figure out where this goes? Maybe it was for the original intake somewhere? :S

10900

geezer101
08-19-2014, 01:01 PM
That is a sensor plug off the AE92 Corolla I've just finished repairing:lmao: (it was the filthiest engine I have ever worked on...) It appears to be unit specific so tracking down it's home should be straight forward job - but considering it's condition I would say it is for a ancillary that isn't used on your truck. Blast it down with some degreaser and see what the colour coding and socket type look like as to give you a clue on what it's purpose is.

coyotefiveoh
08-19-2014, 01:43 PM
well it seems to be very similar to the oil sending unit & coolant sending unit... just slides on a bolt end and measures current/voltage/ohms i assume... i cannot find a spot for it though lol. i will check and see what color the wires are.... its not a usual electrical connection with pins/prongs.

If its any correlation, its on the same part of the harness that goes to the oil sending unit sensor.

coyotefiveoh
08-19-2014, 02:12 PM
looking over some wiring diagrams for this thing.... there is apparently 2 sensors, one for pressure, and one for level.... (this was on one of their gas ones but i think it may be the same so im going to have another look and see if i can find the mysterious unit..... :D