Winnebago Won't Start in Morning & Damp Outside

This product, or similar products, are available at most auto parts stores. Try it on one thing at a time and you will find your problem. First pull off the distributor cap and spray everything inside to see if that works, and then go from there throughout the entire ignition system. Ignition spray

You might be able to narrow down your problem with a hair dryer.

I had a 1974 Datsun 260Z that would not start on cool mornings and it turned out to be the electronics box up under the dashboard above the passengers feet. I'd just run a propane torch over it for a brief second or two and the car would start immediately. And I sure don't remember how I figured that out.

And for another problem I had as a kid. An old dodge would occasionally just quit running. Stop dead. The problem turned out to be in the distributor. It had dual points and the insulation wore through on a wire pulled tight across the moving arm on a set of points. Every few days it would just short out briefly for some reason. I think I found that problem by shotgunning it.

midnightsadie wrote:
just a tempory fix put a 75watt light blub under the hood for the night.

Doing this will further help prove that you have wire, cap, rotor problem as it will dry things up. When it is running you could also mist it with a water bottle, if it gets worse, you have proven even more where your problem is.

Just be careful to not blast it and get zapped. Sort of like peeing on an electric fence.

I had a Silverado 4.3 would not run on after market wires. I also worked on a buddies S10/4.3 that ran rough all the time. He replaced everything, even the intake manifold gasket. I looked it over and suggested buying GM. He said he didn't care how much it cost, he was so sick of messing with it. He replaced the cap rotor and wires and it ran perfect. I know people will say that with newer vehicles troubleshoot and replace only the one bad wire with oem.
The wires I bought and the ones he bought were not cheap, they were the good ones.
Don't do this on what I'm saying, have it checked out, I dont want you to waste your money with my internet evaluation but it is something to consider.
Also try searching for that problem and aftermarket wires, I think I found others saying the same thing.

http://www.gm-trucks.com/forums/topic/66081-random-misfire-on-5-8-running-rough/

http://www.tahoeyukonforum.com/forum/showthread.php?t=30308

just a tempory fix put a 75watt light blub under the hood for the night.

O'Reilly's Auto Parts

You are getting some condensate (moisture) in the electrical system somewhere. Start by unplugging any connections to the distributer, applying dielectric grease to the connections and plugging them back in. If there are connections to the spark control, do the same there. Also, it could be a failing coil, or a bad secondary wire (high voltage, spark plug wire). It starts later because the moisture dries out, and allows the correct path for electrical continuity.

Did you buy the wires, cap and rotor from GM or they after market?