I know this is an old post, but for the benefit of others:
I also have a 93 STS and it does have the 4.6L N*. (I love it so much, I also bought an additional 97 STS!) Anyway, it looks like the procedure given above is the same for the 93. BUT while you're deep within the V of the V8. Do yourself a favor and replace the positive battery cable. Which often is the real problem anyway! Don't forget. Like I did! I installed a new starter, got distracted by cleaning out ALL of the carbon deposits, replaced the intake manifold gasket, and got it ALL back together, turned the ignition. Just to hear it go "click"! After a lot of cursing, I fixed the cable (at the battery end) and it worked fine. I took the old starter to Autozone, and though it had gotten rickety. It tested fine. The moral of the story is. If you have a starter problem or you have power to the instruments. But just get solenoid clicks when you turn the key. CHECK THE POSITIVE BATTERY CABLE AND CONNECTOR AT THE BATTERY END FIRST! Battery acid vapors can and will corrode the wire, even inside the insulation! So check it with a meter. But if you've pulled the intake manifold, and your car was made in the nineties. Just replace the dang thing. AND the MAP sensor, while your at it.
On a tangent. A failed MAP sensor and/or bad or stuck EGR will make you fail emission testing, make the car run poorly, or not run at all. A brand new, but cheap aftermarket EGR valve can make the car run poorly, or not run at all! There's a reason the cheap ones are around 60 bucks, and the factory one is around $250! The PCM is looking for high resolution data from these devices. And if it doesn't get it. You're NOT gonna like it. So take it from a poor dude! Either spend the $250 (the EGR is external to the engine and easy to replace w/ just 2 bolts), or you might get lucky doing what I did. I called my Cadillac dealer and got the part number. Then I searched online and found a brand new one (on Amazon!) For $70! The N* system is SO smart, adjusting it's operation to the way it's driven, that good sensors and feedback control devices are a MUST!
I hope this helps somebody.
Wednesday, December 29th, 2010 AT 12:37 PM