fuel pump in 1985 corvette runs on its own?

My 1985 Corvette's fuel pump started to run on its own (without the ignition on). I did internet searches that pointed to the oil pressure switch as the culprit. Disconnected the plug from the oil pressure switch but the pump still runs. Removed the 10A fuel pump fuse and that didn't stop it (there's still power to the orange wire in the oil pressure switch plug). I also have removed the fuel pump relay. I'm not very confident in my electrical sleuthing capabilities and I really don't know what to do next. My hope is that there's a suggestion from the Forum's electrical wizards that can get me onto a correct track. I'm a new member to the forum.

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if you purchase a ZR13 auto code scanner, from HF,
you need this info
DOWN-LOAD AND PRINT IT OUT!
https://manuals.harborfreight.com/manuals/63000-63999/Q63806.pdf

https://manuals.harborfreight.com/manuals/63000-63999/63806.pdf

as usual start by getting a shop manual and a multi meter, and pulling the trouble codes
a logical step by step approach will lead you to the problem, you'll be amazed at what you'll learn reading links. use of a shop manual and multi meter can be very helpful

http://www.harborfreight.com/5-in-1-dig ... 98674.html

https://www.summitracing.com/parts/anm-cp7838

and rev the engine a few times and watch the fuel pressure it should in theory remain in the 38 psi-42 psi range for most TPI and TUNED PORT efi

a vacuum and fuel pressure gauge is useful

obviously an electric fuel pump in the fuel tank running is connected to a current source
you should logically be able to locate the source of that current by either pulling the fuses to any component that it might be related too. or tracing the wire feeding the pump back with a multi meter.

BTW it generally helps if you post the city and state your in,
as theres at least some chance a local member,
may want to stop by and help you diagnose,
and maybe help rectify the issue if your LOCAL


with the 1984 and newer computer controlled corvettes, you really need a old computer, an ADL cable and matching software to read the trouble code info and of course a shop manual for YOUR YEAR CORVETTE, and a MULTI METER
reading links may seem like a waste of time , but having a shop manual, a decent up-to-date, scan tool and a multi meter and a good understanding of what your testing and why your testing it helps a great deal
like the old saying how do you eat an elephant ?......one little bite at a time!

all the answers are readily available, theres known testing procedures and listed test results you can expect, and procedures listed in the shop manual for isolating and testing components, you don,t need to be a genius, you just need to be logical and persistent and not afraid to learn new things while getting your hands dirty at times, don,t get overwhelmed , break everything down too easy individual problems and tests, verify and test all the sensors,and test for factors like consistent fuel pressure, known temps,expected voltage or ohms resistance, and vacuum readings and don,t randomly start replacing parts as that gets expensive and its rarely the most efficient way to eliminate problems(unless you get really lucky) with modern computer diagnostic software you,ll have some advantages but think logically, most automotive problems still concern, compression, fuel delivery ,fuel pressure, vacuum, temperature or electrical issues.