My 1998 Camry's 4-cylinder engine does not run well in high humidity.

It sputters and will not accelerate.

It takes a long period of warming before it runs well.

What might be the problem?

Thank you for your help.

 

my thoughts

maf is the part that has the atmospheric /barometric sensors built it
give maf a clean and its plug contacts of corrosion

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clean or replace the air filter

if no better
make sure the 02 sensors are ok

 

Where is the MAF located?

 

Does it run poorly after a cold start as in sitting over night?

Does it eventually run well when the engine gets hot. Perhaps then running well until it sits over night?

 

It runs poorly after a cold start after sitting over night.

After it warms, up it runs fine.

 

Moisture could be causing issues.

Check the ignition system coils and high tension wires.

You could use a hair dryer to heat the ign system components, sensors, etc one at a time to simulate a warm engine condition.