Did you manually clear the codes ?
Yes the Switch Hosting (Plastic) can leak due to Heat over the years.. Just replacing the switch can help it a lot..
bad check valve or a leak.
That indicates a fault and the switch needs replacing.
Possibly, the power steering pressure switch changes the idle if there is more pressure due to use of the power steering it will increase the idle. A bad switch could be sending faulty informatioin causing your idle to be wrong and the car could stall. These switches cost about $30-$35 and depending on location take minutes to change with a couple wrenches.
A bad fuel pump can cause stalling. The oil pressure will show low oil on the lights or gauges but if the pressure is ok then the switch should not cause stalling.
It could cause a high reading on the gauge.
Only if installed incorrectly
I had the same problem. I took it to a mechanic and they told me it was the ignition switch.
No it will not.
Assuming you have replaced the fuel pump relay, try replacing the engine oil pressure switch/sending unit. It doubles as a safety switch for the fuel pump.
Yes it could.
check the oil level in the hpop.