I could really use some help.

I just changed out the water pump with me and friend on my 110K car 300 miles ago and now my car refuses to start when its rainy or very wet outside. I know I should have changed it out the opti then but i didn't have the time. It cranks and cranks, burbles a bit but barely seems to get a spark.

After a day or so when its not raining and humidity is lower the car starts right up, albeit a little rough for a second or two and then its normal.

I'm pretty sure its the opti and i guess there's some water in it? does the high humidity just tip it over the edge of not passing a spark? And it dries up enough on normal weather days?

Moreover, is there any way to remedy this without having to go through the bitch process of taking out the opti? like maybe draining it in some way? I'm planning on changing it out but i dont have the tools or resources to do it until May (i'm in college and live in a dorm)

Thanks

 

Do you have an ignition box and if so, where is it mounted?

 

ignition box? do you mean the coil?

where's the ignition box on an LT1?

 

i think he was refering to an msd box like a 6al, which would be aftermarket.

 

i dont believe so i think my opti is stock but then again i am the third owner so not sure. It definitely doesnt look like an MSD opti

any suggestions on what I can do?

thanks

 

Same thing happened to me before. It ended up being the pos elite sparkplug wires.

 

so do you think i should try to change out the sparkplug wires? I had new plugs put in a few months ago. Compared to changing the opti plug wires shouldnt be too bad right? a couple hours i guess

 

i had that happened to me before and it turned out to be my ignition module. Same symptoms.

 

Let's see: Your WP went out. It may have Pi$$ed on your Opticrap before dying, or you gave the opti a bath when you changed the WP.

It may not be the opticrap, however, they do not like to get wet and if it did then it is time to get another one. Having said this about that, you should still eliminate the other simpler possibilitie before you tackle the distributor. JMHO

 

Check for corrosion on:

-Optispark harness connectors (2)
-plug wire terminals on the Opti
-coil wire terminals on the Opti and coil

In a dark area, run the engine and check for signs of arcing on the plug wires and coil wire, and on the coil itself. Spray a light mist of water on the wires to simulate the high humidity conditions.

 

I have had the same problem for 4 years and it started after i changed my water pump too. i was not sure if it could be related to the opti but didnt want start changing parts not knowing if they were the cause. what i also notice, is if the car sits overnight and i turn the key to the on position without trying to start it, the engine fan comes on HIGH. I follow by trying to start it and it wont catch. Whenever the fan is on high before trying to start, it wont start. If i keep turning the key from off to on, when the fan eventually doesnt come on, the car will start and be fine.

 

I had the same thing happen. the car would die in the rain a puddle even the carwash. It turned out to be the distributor. Good luck with it.

 

change your coil... this is normally the cause.

 

I changed out the plugs, wires, coil, and ICM. Also added some dielectric grease in the connections, and it doesnt happen as often, but it still happens. The other night after it rained it wouldnt start just cranked. I re-primed the fuel pump and it started but was definitely down in power and running a tad rougher. Almost like it lost a cylinder. Next day it was fine.

I'm guessing its the opti, the only ignition thing I haven't changed right?

 

it's odd that every time before it happens, i turn the ignition to the on position without trying to start it and the fan goes on high. What would cause the fan to kick on high if the car is cold? Could the coolant temp gauge be bad, sending a signal and causing the computer to turn the fan on high? Would that then signal the computer to cut spark? The temp gauge on the dash is reading ok though.

Since the fan issue goes hand and hand with the starting problem, maybe we can explore what causes the fan to react the way it is.