# 1994 4runner Engine runs rough when it rains or is wet outside

**URL:** <https://community.cartalk.com/t/1994-4runner-engine-runs-rough-when-it-rains-or-is-wet-outside/40953>\
**Category:** Maintenance/Repairs\
**Tags:** electrical-wiring, rough, engines, toyota, 4runner\
**Created:** [December 19, 2009, 6:42am UTC](https://community.cartalk.com/t/1994-4runner-engine-runs-rough-when-it-rains-or-is-wet-outside/40953 "2009-12-19T06:42:51Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![bennettaeb](https://avatars.discourse-cdn.com/v4/letter/b/4af34b/32.png) [@bennettaeb](https://community.cartalk.com/u/bennettaeb)\
**Post date:** [December 19, 2009, 6:42am UTC](https://community.cartalk.com/t/1994-4runner-engine-runs-rough-when-it-rains-or-is-wet-outside/40953/1 "2009-12-19T06:42:51Z")

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My car has terrible acceleration when it is wet outside. There is only power in the first half of the gas pedal. By that i mean you cannot accelerate if you depress the gas pedal more than halfway. The engine RPM’s increase but speed does not. I can hear the engine misfire and knock. Have recently replaced plugs, wires, cap and rotor. Had a new egr valve and tempersture sensor as well. I am completley lost on what could cause such a loss of power. I know it only happens when its wet because when its dry i can get on the highway and accelerate fine. However, when its rainy, there is no power to accelerate onto the highway. Please HELP!

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [December 19, 2009, 9:26am UTC](https://community.cartalk.com/t/1994-4runner-engine-runs-rough-when-it-rains-or-is-wet-outside/40953/2 "2009-12-19T09:26:40Z")

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Moisture could be seeping into the ignition coil, or a wiring connector going to the ignition coil. Spray the ignition coil, and wires, with silicone spray and see if that helps.