Isn't there a failsafe mode in the pcm that tells the car not to start if there isnt any oil pressure....hit me if iam wrong....

I have a '92 Factory Service Manual, and I've been trying to research this a bit. jr's3800 says try a new oil pressrue sender switch, and that fits with your description of an indication of high pressure. Here'* what the manual says:
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Oil Pressure Gage Short Test

Disconnect: connector
At: Oil Pressure Sender/Switch

Condition: Ignition switch: RUN

Action...........................Correct Result................For Diagnosis
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Disconnect Oil.............Oil Pressure.........................See 1
Pressure....................... Gage reads
Sender/Switch...............High Pressure
connector


If the result is correct, replace the Oil Pressure Sender/Switch

1. Check TAN (31) and TAN/BLACK (231) wire to instrument
cluster for a short to ground. If wires are OK, replace the
instrument cluster
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So, if you have high pressure indicated when you shouldn't, either the sender is bad, or the connector may be corroded, or loose, or off, or you may have a bad gage.

If 1nt 53185 is right, that would cause the no start problem, but I cannot find a reference yet as I peruse the manual. I'll keep trying.

There is a failsafe. I've seen it. It either cuts of the fuel or the spark (I think it'* fuel) if oil pressure is lost.

That'll likely be your problem. The oil pressure sender is inexpensive and fairly easy to change.

OK, I found a reference to the oil pressure switch and the fuel system, but not quite what we are looking for. Here'* what the FSM has to say about the Fuel Pump Electrical Circuit:
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"When the key is first turned "ON," the PCM turns the fuel pump on for two seconds. This builds up the fuel pressure quickly. If the engine is not started within two seconds, the PCM shuts the fuel pump off and waits until the engine starts. When the engine is cranked and the rpm signal has been detected by the PCM, the PCM supplies 12 volts to the fuel pump relay. This causes the electric in-tank fuel pump to run.

As a backup system to the fuel pump relay, the fuel pump can also be turned on by the oil pressure switch. The oil pressure switch is a normally open switch which closes when oil pressure reaches about 4 psi. If the fuel pump relay fails, the oil pressure switch will close and run the fuel pump.

An inoperative fuel pump relay can result in long cranking times, particularly if the engine is cold.

An inoperative fuel pump would cause a no start condition. A fuel pump which does not provide enough pressure can result in poor performance."
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I'll keep looking to see if I can find any additional references to the oil pressure and the PCM, or other info that might help you get this bugger started. I sure am curious.

Description and Operation

When the ignition key is first turned to the "ON" position, the ECM will energize the fuel pump relay for two seconds. This increases fuel pressure for cranking. If the engine is not running within two seconds, the ECM will shut off the relay and wait for a "START" signal. As soon as the engine is cranked, the ECM will energize the relay and power the fuel pump. Once the engine is started, the oil pressure switch provides power to the fuel pump. The pump will then continue operating as long as the ignition is "ON" and there is engine oil pressure. If oil pressure is low (enough to possibly cause engine damage) the oil pressure switch interrupts power to the fuel pump.

NOTE: The fuel pump relay can be bypassed at the oil pressure switch to operate the fuel pump. Also, a faulty oil pressure switch can cause the pump to run continuously whenever the ignition is "ON".

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If the pressure doesn't come to about 40-47 PSI upon truning the key on, the oil pressure switch isn't to blame. My 90 had a faulty regulator which led to hard starts but the pressure climbed into the 30'* within the 2 second prime.

There is a test lead for the fuel pump behind the battery. If you apply a fused +12 volts to it with the key off, the fuel pump should enegerize and pressure should build.

Thanks Randy and Bill. Now I can quit searching through this never-ending FSM. Sure looks like a bad sender.

That makes sense. I ordered the new pressure switch this afternoon. The local parts store was going to drop it off, but didn't. I'll pick it up in the morning and give it a try. I know I have fuel pressure when I first turn the key on, I hooked up a pressure gauge and the fuel pressure is as it should be, and when I turn the key on I can hear the fuel pump relay click on, and when the car shuts off, I can hear the fuel pump relay click off. I'll let you know the outcome tomorrow.

Installed the new oil pressure sending unit, solved the fluctuating gauge problem , but the car still will not run for more than a few seconds before it shuts off. I am going to run a fused 12 volt to the fuel pump and see if I have any luck with it staying running. I already changed the relay for the fuel pump. The warning light still comes on with "check gauges" and "check oil level" . Could I have possibly fried my oil level sending unit as well as the oil pressure sending unit ?

Is there a failsafe for the oil level switch....I know mine lights up and chimes at start up...self check mode i assume....

When the car starts and then stops running, I get the "check gauges" and "oil level low" warnings. When I put the key in and turn it to on, I get the "normal " start up lights .