car seems to lose power when under full load, code 1381

2002 HONDA ACCORD
88,000 MILES • 2.3L • 4 CYL • 2WD • AUTOMATIC
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MARKJOHNSON
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A/C, lights, radio, etc. it shifts gears but with a hesitation and around 40 mph the check engine light comes on. Code P1381. Seems like power is lost as soon as check engine light comes on.
May 3, 2019 at 4:51 PM
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SCGRANTURISMO
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Hello,

This Direct Trouble Code (DTC) is for an intermittent fault in the CYP Sensor in your vehicle's distributor. I have included in the diagrams down below a Diagnostic Troubleshooting Guide from Honda on DTC P1381, along with a Technical Service Bulletin (TSB) from the factory on this DTC. You will have to use a multi-meter to do some of these tests so I have included a link below if you are not familiar with how to use one.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Please go through these guides and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
May 5, 2019 at 10:29 AM
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MARKJOHNSON
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Hey SCWICKEDSTANG, I just checked the alternator and battery. The battery has 12.5 volts with engine off. With engine on the level only is raised to 12.8 volts charging the battery with no load. Shouldn't the alternator be boosting the level above between 13-14 volts? I'm asking could it be the alternator? Thanks for your info. Just received it and am checking it out.
May 5, 2019 at 5:58 PM
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SCGRANTURISMO
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Hello again,

What is required for your vehicle's battery to charge is for more voltage to be applied to it than it has stored in it. Having said that, here is a link for you to go to below:

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Please go through this guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
May 6, 2019 at 2:31 AM
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MARKJOHNSON
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Hey SCWICKEDSTANG Expert,
Thanks for everything. The problem was a bad alternator, although brand new it was a defect.
May 9, 2019 at 3:16 PM
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SCGRANTURISMO
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Hello again,

Bad parts right out of the box happen. We're glad you got everything straightened out. It's what we like to hear.

Thanks,
Alex
2CarPros
May 9, 2019 at 6:38 PM