So I have a fairly new to me 1992 that I just finished a light tear down on motor to replace water pump. I didnt get crazy but I did a full flush of coolant by removing Knock Sensors, rebuilt the throttle body and bypassed the coolant line to it. Replaced radiator, thermastat (changed to 180 from factory ~190) and spark plugs.

First startup it wouldnt fire either. I somehow realized the security light was acting different and cycled the driver door lock, turned ignition over and she roared back to life. Ran smooth with no issues for a couple days.

Came home other night, parked in driveway, meaning to return to pull in garage. I didnt make it by fluke and she spent night outside.
Went to start, and just cranks over and over. I changed nothing what so ever from parking the night before when it was seemingly running exceptionally well.

I also noticed that I had managed to burn somewhere short of a Half tank of gas in something like 8 miles.
I am not ruling out the idea that the gas was taken over night, and car maybe tampered with.

Codes I get are Mod 4 - 41 and Mod 9 64

I have been getting mixed results as to what code 41 exactly is, because in my book it lists it as Ignition Spark Control, having a short to Voltage. I have seen it listed as Cylinder Select (?) and something else.. however, a couple times i caught myself looking at the book under the ZR1 section..

Any help would be great. Im sure its a wire, or i shorted a component?

Security light in dash flash;s when door open, goes out completely when key is turned ON or START.

 

You should get factory manuals to DIY. The code has to do with ICM ECM and circuit between them. The lt1 is unique that the distributor (opti) sends signal to ECM and ECM turns on ICM. Some auto parts stores will test ICM for free. The white wire at ICM term B is ignition control from ECM. You might look for trouble tree for code on net.

 

Impossible to burn 10 gallons of gas in 8 miles without it leaking out.

 

Yes, Whaleman, my thoughts were similar to that conclusion as well. If I remember correctly, I did have a couple other words that carried a little more definition to them.. (or less?) Anyways, I have to write that one off I guess. However, quick side question.,., Where would I look for any clever tampering from a gas thief? The filler/sending unit looked clean, no clues.

Kevovam I do have the FSM's and they are great. I neglected to mention above that there is slight learning curve to these books, even for a guy like me that has been reading Automobile service manuals as far back as I can remember. Specifically the whole VIN J sections! My GOD how many times, no.. how many MORE times will I read over an area only to find when I am finished.. it was for the ZR1

I do know my way around the shop. Turning wrench's on cars 35 years or something, and thats why I am here. From time to time you run across something you are so familiar with, yet knows so very little

I am just about to probe around there as matter fact. I have the engine's wire harness pulled up to go over those connections, and almost done

 

I hope you have a locking gas cap? The 92 cars should have come with a FSM and no other book can compete with the car s functions.