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1995 Tacoma i4 5spd manual 2wd

This truck misses in the morning when I first start it. It acts like it did when the catalytic converter went bad. Only so much gas can be given, before it sputters and misses. This only happens when it is humid or raining. When the truck warms up, the problem goes away, and once it is warm, it doesn’t happen again during the day.
I would suspect an exhaust problem, but I just replaced the entire system from the exhaust manifold back.
I’m now suspecting a problem with the ignition, but I don’t know where to start to find that problem

It sounds like a classic case of worn out secondary ignition components.

If you don’t know or can’t remember the last time these components were serviced that’s where to start.

Tester

+1 to Tester’s comments.
Ignition components can, over time, begin to become affected by wet weather. A Haynes manual, available at the parts store, should help you to go through the process of getting your ignition system up to snuff.

Given the symptom/ described it certainly sounds like a bad plug wire or some other ignition component. The wet/humid condition simply taxes the electrical system more and reveals the underlying issue.

I third the above remarks. Had a couple of these trucks…great vehicles but they all show their age in humid weather, more so then in cold. If the harnesses haven’t been changed, it’s well past time.

The next time it acts up you might also pop the distributor cap off and inspect the inside surface for moisture.
What happens sometimes is that depending on the climate a warm engine will absorb moisture after it has been shut off. The inside of the cap may resemble a sweating window pane.

Spraying it down on occasion with WD-40, etc. can help to prevent this.