One of my winter projects will be doing a basic tune up on my 95 LT1. Wires are brittle and are arcing at idle, causing a rough idle condition especially when hot. My problem is that these wires may not be original, seem to be routed by braille, and some of the original routing looms are missing or the locations of same are in the wrong spots. Being that my car came to me with a mount on the valve cover for a coil per cylinder system, I’m guessing my car was switched over to that and then switched back to full opti function. So that brings two concerns. One, is that I would like someone with the factory correct routing to send over some photos of the routing and loom locations so I can purchase new loom brackets and do it right. Secondly, since this car was obviously messed with, I’d like some opinions on whether I should just replace the entire system, including a high quality optispark (Petris enterprises??) or just do the cap and rotor, wires, and plugs. I’m also going to do the water pump while I’m in there. That will give me some added access room and will provide insurance against the obvious issue of the pump seeping on my new set up. With that alone, I’m considering going electric with the Meziere HD unit. So opinions on that too please. Finally, while I’m doing ALL that, I’m considering just doing the full front seal kit. The car has 73k on it, and I definitely have some oil seepage in the front that I don’t think is coming from the intake (though I might as well pull that and reseal it too). So your opinions on doing that while I’m in there please. This is one of those projects that can really snowball but I want to do it right and do it once. Since my long term plan is to have the heads and intake worked and install a cam, I was just going to wait on everything and just do the tune up. But with my kids activities and everything else, it’s not in the budget for at least a few years. Especially considering the cost of supporting mods for the tune, exhaust, and upgrading things that will break at that power level. All opinions and photos welcome!!! Final question is would the FSM for my year car show the routing and loom locations? If so, I will try to pick one up. Thank you.

 

What does it look like behind the water pump and around the opti? Is everything dry as in no evidence of oil or coolant leaks?

If it’s dry and you are planning more extensive work in the future, I would suggest doing the plugs and wires only for now and see how it runs.

If you insist on doing more, pull the pump and at least do a new distributor cap, unless you see evidence that the cap had been recently replaced.

The 95 Corvette came with an unvented opti. Do you still see that type? If not, try to confirm whether or not any modification to vented was done properly. If it’s still unvented, it can be modified to vented.




If you do pull the water pump you should at least replace the water pump drive seal (tricky) and the opti drive seal. (Less tricky). Having the pump off should make doing the ignition wires a little easier.

 

It’s a little hard to see behind the water pump but I will try to take a closer look. My understanding was that the 94-96 vettes got the vented opti. Or at least the 95-96 years did. Based on the amount of gunk that’s forming on the front cross member, I know I have a leak somewhere but that could just be the front crank seal. I’m leaning toward just the tune up now, including the cap. So that would require removing the water pump. I’d like to at least get the cap off to inspect the optical sensor and check the cap. That will also allow me to get a direct look at whether the seal might be leaking there too. If there is any gunk above that, it could also be the front intake silicone seal. My oil level never drops but I have a considerable oil/grime coating on the undercarriage all the way back to the rear. I’m thinking that might be a separate issue, maybe rear intake, rear main, oil pan, or oil filter adapter. I really want to track all of this down but the way my mind works is a giant snowball effect. I start doing a tune up and next thing I know the engine and trans will be on a stand and my wife will want to kill me when thousands in parts start showing up.

 

I just looked it up again. 95-96 have vented Optis. And the 97 camaro, last year for LT1.

 

My mistake on the 95 being unvented. When you get into the opti look to see if it has a Mitsubishi sensor. If so that’s a good thing.

 

That I will definitely do. If it’s not the original opti with Mitsubishi sensor, I will likely replace the whole thing. I’ve heard too many horror stories about aftermarket optis shitting the bed after a short time. I’ve only owned this car for a year and a half and barely put 400 miles on it. I wish I could ask the PO what the deal was, especially with the Delteq mount on the valve cover, but he’s in hot rod heaven. Once I’m there who knows. If I’m yanking it, it will get the seal kit too.

Anyone have info/photos on the factory routing or if the FSM contains those details?

 

Here's another thing you can do while the pump is off to help out the opti. Install a nipple in the weep hole in the pump housing. Connect a hose such as vacuum line and run it down to the K member and secure it there. Have it just long enough so you can see it peeking below the K member if you look under the car. Now, if the pump shaft seal ever leaks, the coolant will drip out of the hose under the car instead of on top of the opti.

 

I will definitely be doing this if I don’t go electric. I do like how the electric pump eliminates any possible coolant leak and oil weep at that location with the elimination of the shaft. One less thing coming through that timing cover seems like a good idea to me. As long as the port is well sealed.

 

One thing I just realized is that I can use my dads car as a reference. He’s got an untouched, completely stock LT4 I can park next to mine as I’m doing it. So that problem should be solved.

 

Nice, that should work. I have done the same in the past but with Foxbody Mustangs. I have a stock configured 92 LX then bought a 93 LX convertible that had been totally jacked by previous owners including a hack job wire tuck and all. I was able to get it back to decent configuration by referencing the other car. I had them parked nose to nose.