Several questions.

[Paul Higg]

94 LT1 90,000 miles.

1) Should I replace the transmission fluid?
2) Should I have the injectors cleaned?
3) Should I replace the spark plugs and wires?

4) Should I stand on my head and spit wooden nickels?

Please help with 1-3.

Thanks, Paul

 

[Tuna]

Do you know when/if any of that stuff was done before?

If not, then yes to all 3.

 

[Paul Higg]

Looks like yes to all three.

Thanks again Tuna. I got the car in January and I have no idea how well it was maintained. So I am "zero timing" everything out.

How hard is it to replace the plug and wires? I have read somewhere that it can be a real BI**H.

 

[B17Crew]

You may find this thread on C4 injector cleaning interesting.

http://www.corvetteactioncenter.com/forums/showthread.php?t=23448&highlight=c4+injector+cleaning

B17Crew

 

[twiget]

How hard is it to replace the plug and wires? I have read somewhere that it can be a real BI**H.

The plugs and wires on an LT1 is a serious PITA. I did them on my old '96 LT4, took me all day. Personally if I ever have to change the plugs on an LT-series motor again, I'll take it to a Corvette shop and pay the $$$. :W

Jason

 

[Paul Higg]

Thanks B17 for that link. I will try the Lucas brand.

Also, thanks Jason, I will do that, Corvette Country doesn't charge that much and I really do not want to mess with them.

 

[B17Crew]

You’re welcome!

B17Crew

 

[Tuna]

Changing plugs and wires on an LT1 C4 is awful. Shop time is like 2 hours but I've never seen anyone do it in that time. You have to take the front and rear inner fender panels loose just to get the room needed to reach the plugs. I'm with Jason, I'd pay someone to do it.

 

[Paul Higg]

Yeah, that's what I'm gonna do.

Thanks Tuna.

 

[gmjunkie]

Changing plugs and wires on an LT1 C4 is awful. Shop time is like 2 hours but I've never seen anyone do it in that time. You have to take the front and rear inner fender panels loose just to get the room needed to reach the plugs. I'm with Jason, I'd pay someone to do it.

The Plugs aren't bad,But the wires on the drivers side "Flat SUCK"!!!!

 

[jrogensk]

After doing the plugs, wires and water pump a week ago (and not doing the opti) I decided that if the Opti does go out I am selling the car and getting a C6.

I don't want to do it again. :W

 

[JimBobC4]

So, I have about the same number of miles on my '95 as well. I am plannning on replacing the plugs and wires. Should the OPTI be replaced with the plug wires even if nothing misfires ? Does the OPTIspark have components similar to a distributor cap (wearable spark distribution contacts) in it ? :confused

 

[gmjunkie]

So, I have about the same number of miles on my '95 as well. I am plannning on replacing the plugs and wires. Should the OPTI be replaced with the plug wires even if nothing misfires ? Does the OPTIspark have components similar to a distributor cap (wearable spark distribution contacts) in it ? :confused

Yes it has a cap and rotor button of sort!!
I wouldn't fix it if it is not broke!!!But you will get many,many opinions on this,the Opti-Spark gets blamed first thing!!:L:L:L If your going in to get the Opti,you just as well put a New water pump and idler pulleys and do some other maintenance work too!!
If it's Not Missing or throwing any codes, I'd change out the plugs and maybe the wires!!
Other than that,If it Ain't Broke,Don't fix it!!

 

[rascal_rascal_99]

I pretty much agree with what Junkie said, although unless you have a problem with the wires all I would change is the plugs. If I was going to change wires, it'll be incredibly easier to change them with the water pump off...just look at your motor and you'll see where they disappear to in front of it and I think you'll understand why...and if I'm pulling the water pump, it's getting replaced, and if I've gone that far I'm also doing the opti. If it runs smooth and doesn't have a miss at all, isn't giving you any signs of problems, I doubt I'd change anything besides the plugs...other than just the mileage on the car, do you have another reason for wanting to do this?

 

[Paul Higg]

I thought since it was at 90K I'd change the plugs. It's running okay except for hard starting in hot weather but Junk and a few others have "learned" me on that.

 

[Toms007]

Alright, I'll get on the band wagon as well. Plugs, yea, I'd go ahead and swap those out (not really that difficult). The wires are kind of a PITA.

Now with all that said, here's what I have done. I had a little oil leak on the front of the engine. Intake manifold gaskets had already been done so that left me to believe that one (or more) of the seals on the timing cover was the culprit. So I decided to fix the leak. I knew that I was going to be removing the water pump and opti to get to the seals on the front of the timing cover, so I bought new seals for the timing cover (w/p, opti and crank), water pump, opti, plugs, wires, idler pulleys and serpinetine belt.

Like you, I wasn't sure when any of these things had been done (except plugs), and beings I had it all apart anyway I figure it's easier to do it once than to re-do it later. Wires were definitely easier with the w/p out of the way.

 

[Paul Higg]

Tom, you obviously know a LOT more about doing stuff like that than me. My wife and I only have this car. She's a severe diabetic so she can't drive (too many wrecks in her past). Anyway, I think I could probably do all that work but it would take time and planning. I have the FSM so that'll help but if I need something in the middle of a job I'm stuck.

PLUS, don't you hate the way this engine is so cramped that you couldn't fit a fart in there?

 

[JimBobC4]

other than just the mileage on the car, do you have another reason for wanting to do this?

1. Mileage ( 87k)
2. I've been reading about the OPTISpark dying on here for years. I've also noted the OPTI has been blamed for everything from Global Warming :W to failed PCM's on the LT-1 cars. (I'm a past Z-28 owner)

However,my car runs great and I don't drive it very much at all. My buddy who runs a little repair shop says if the plugs and wires get too much resistance (plug gap) it can make the OPTI die as well.

 

[rascal_rascal_99]

Tom, you obviously know a LOT more about doing stuff like that than me. My wife and I only have this car. She's a severe diabetic so she can't drive (too many wrecks in her past). Anyway, I think I could probably do all that work but it would take time and planning. I have the FSM so that'll help but if I need something in the middle of a job I'm stuck.

PLUS, don't you hate the way this engine is so cramped that you couldn't fit a fart in there?

Things are cramped...but look under the hood of one of the last runs of camaro's or firebird's, it's insanely worse. Honestly I think I'd go with the "if it aint broke don't fix it" theory. With no other transportation I'd look into the possibility of seeing if you can borrow a friends car just to be safe over the weekend you plan to do it if you do change more than plugs.

1. Mileage ( 87k)
2. I've been reading about the OPTISpark dying on here for years. I've also noted the OPTI has been blamed for everything from Global Warming :W to failed PCM's on the LT-1 cars. (I'm a past Z-28 owner)

However,my car runs great and I don't drive it very much at all. My buddy who runs a little repair shop says if the plugs and wires get too much resistance (plug gap) it can make the OPTI die as well.

When I got my car it had 102k on it and I have no idea when any of this stuff was going to go out on it. I bought the parts and was prepared, halfway expecting things to go out, it's been three and a half years and about 56k miles later and my waterpump started to seep just a little out the weep hole on it, so I took that as my sign that it was time to do the work.

I will admit that not long after I bought it, I did do the plugs and wires without removing the waterpump, my reason this was I was putting in an MSD box that required heavier wires and have since gone to a total MSD ignition system (wires, 6AL box, coil, opti). The only way I ever managed to get the wires plugged into the opti without pulling the water pump, was I found a piece of pvc pipe to modify to shove them onto it with. I was trying to find it to take a picture, but have no idea what's happened to it. The basic concept is that you don't have enough room to push the wires onto the opti and plug wires aren't stiff enough to just push on. I found a piece of pipe about a foot long that the inside diameter was just big enough for the plug wire to fit in, but too small to slide up over the boot on the end of the plug wire. I cut about 1/3rd of it out length wise with a dremel tool (two cuts lenthwise), so now I could squeeze the plug wire into that and use it to help shove the boot onto the opti until it seated on. Hope this makes sense.

 

[Paul Higg]

Thanks Rascal. I think I will let my mechanic at Corvette Country do it as he has 32 years of experience restoring Vettes.