oil pressure sensor plug replacement
 

I recently replaced my oil pressure sensor plug on top of my oil pump because the old one was melted/corroded. The new one was color coded the same as the old so I soldered the new plug in place, but no my '87 t-type WE-4 will not start. Is there something I need to reset or something..... I am at a total loss what to do next. Can I bypass the sensor all together to get it running?

Re: oil pressure sensor plug replacement
 

This is just the electrical harness plug, right?

Does your fuel pump run briefly when your ignition switch is turned to the 'run' position before you turn it to 'start' and crank the starter? If not, that confirms there is a problem. But that does not guarantee that is the problem. There are a LOT (7, actually) of connectors in the harness between the battery and the fuel pump.

You could try shorting the wires in this connector and see if it makes a difference. If so, it may just indicate a bad connection. The oil pressure switch doesn't have pressure before cranking, obviously.

Re: oil pressure sensor plug replacement
 

check the fuses. I went threw the same thing when mine melted/rotted
It shorts out and blows a fuse. It may have been the PCM fuse

Re: oil pressure sensor plug replacement
 

thats what i did and went with auto meter gauges

Re: oil pressure sensor plug replacement
 

yes, just the harness plug is what I replaced. The fuel pump does kick on when the ignition is in run. I had previously checked all the fuses b/c I thought that may be the problem. To short out connector what do I do. Does the oil pressure sensor just work like a relay and when pressure is built up it closes the circut or what?

Re: oil pressure sensor plug replacement
 

unplug the connector.
turn the igntion on, and check all the fuses , "with a test light on both sides of the fueses"
tell me what you find

Re: oil pressure sensor plug replacement
 

I checked all the fuses for continuity with my fluke, and they all checked out. With and without the "plug" in place. The only difference was with the "plug" undone, the fuel pump wouldn't kickon when in run, and no voltage was seen accross the fuse. I don't know if this information helps at all, but let me know what you think, and if you have any other suggestions. Again, is there anyway to bypass this sensor temporily, I want to move my car to my new place, and I can't get it started. Would a scan tool be worth investing in for this problem? Which ones whould you recommend. Thanks again for your time, and suggestions.

Re: oil pressure sensor plug replacement
 

I'll have to check the diagram when I get to the shop. The oil pressure sender is part of the fuel pump circuit usually. The oil pressure comes up and the oil pressure sender closes the coil in the fuel pump relay and keeps the fuel pump going even if the ECM fuel pump control is lost. Normally, the ECM is the one that initially closes the coil in the fuel pump relay when the key is turned on, or if it sees circuit 430 (ignition pulse from the ignition module) active. Sounds to me like if you have a 3 terminal oil pressure sender, you may be grounding the circuit that energizes the coil in the fuel pump relay. Strange that your car will not run with the oil pressure sender disconnected. I think it should. Using an ohm meter is a bad way of checking fuses. Use a test light instead and go across each fuse in the fuse box and see if the circuit is live. You can also disconnect the TPS and use your Fluke on a DC volts scale and see if you have the 5 volt reference to your TPS with the key on. That'll tell you if the ECM has power to it or not.

Re: oil pressure sensor plug replacement
 

http://krylonracing.com/paceGN/PICT0009.JPG

i know for a fact the fuel pump will run with out the oil sending unit on there, I totally removed it from my harness.
My plug was all oil correded and the wires would short out on block and blow the fuse.
Do you have a hot wire kit for your fuel pump?

Re: oil pressure sensor plug replacement
 

Hey if the car cranks and the fuel pump is running maybe it not anything to do with the computer at all. It may be possible you have a bad crank or cam sensor. Sometimes when things sit over night the evil car demons strike at something else. sometimes bad things come in pairs. At my shop we have strange unexplained things happen to vehicles overnight.