I am changing plugs and wires on a 94 LT1.

Any suggestions on how to access distributor cap for wire installation with minimum take apart of engine?

Where can i find out how to checxk error codes to see if the Opti needs to be replaced?

 

Not that I have one yet but the shop manual is a great thing to have. Changing wires and plugs is a long job on these things. Which is why I haven't done it yet.
just changed the spark plugs on my '93 yesterday and I have to say, I don't really understand what all the talk is about.

On the passenger side, I was able to change every single spark plug without removing anything and on the drivers side, all I removed was the tire and the wheel well. Obviously those small steel things bolted to the heads to keep the spark plug wires straight came off too.

The passenger side rear ("dreaded" #8) wasn't hard at all. I used a Snap On spark plug socket, a u-joint, an 8" extension, and a swivel head ratchet to remove it. I ended up getting a bad angle on the u-joint the first time and broke the spark plug in half but that just made it easier to get to I guess, LOL. I had to face away from the car and reach in backwards to get the spark plug socket on it but that was about as complicated as it got.

To put it back in, I had to reach in backwards again and used that same Snap On socket. I used a Gear Wrench on the hex fitting that it had on the end (a regular wrench would have taken forever) and tightened it down without any problems.

The other three on the passenger side were absolute cake. I ended up using a different Snap On spark plug socket to do those. It had a built in extenion/swivel which made it very easy to get the spark plugs started back in. I was able to do the entire passenger side within the engine bay, not even going into the suspension area or anything.

For the drivers side, I removed those stupid spark plug guide clip things from the head and unplugged all the boots from each spark plug using a pair of long needle nose pliers. Next, I used that same Snap On swivel/extension spark plug socket and added my own 10" extension. I was able to get to all the plugs perfectly by removing the center and right wheel well pieces and sticking that snake of a tool I made straight through to the head and was able to access every single spark plug. It was literally easier than the passenger side once the wheel well was off.

I don't really understand why I'm reading about going underneath the car, unbolting the power steering pump, etc in ordert to this. In summary, I guess I should be happy because it less than 3 hours, lol. I didn't even need a beer. Oh, and if anyone wants part numbers for that Snap On sockets I used, let me know.
This might help. From another post.

 

At a minimum, you will need to remove the waterpump to gain access to the Opti connections.

Here is the "paper clip" method for retrieving error codes. (If your '94 has a 16 pin ALDL, then you will need to short out pins #4 and #12).

http://www.troublecodes.net/GM/

 

I just replaced the plug wires on my '95. No need to remove the water pump.

Right side was simple, you can reach around the front of the engine and get at the plug wires on the OPTI.

Left side was difficult. Here's what I did and it worked out well.

1. Removed belt.

2. Removed altenator (probably didn't need to but makes it easier to see).

3. Removed belt tensioner (one bolt).

Now you can get at the plug wires on the OPTI. One more step is needed before you can route the wires.

4. Removed bolts from power steering pump and rotated forward a little.

Now you can get the wires behind the power steering pump and through the hole in the accessory bracket.

It took me a couple of hours but once you remove the belt tensioner it makes life much easier.

The only thing I remove when changing plugs is the ASR actuator on the left inner fender.

 

I was able to replace wires by removing the serpentine belt and tensioner, it is easier to reach some wires on the cap from underneath. Tedious but not really difficult.

 

mfi are you running headers or stock manifolds? They are a pain in the azz compared to other chevys.