I have an 2004 Ford Focus LX 2.0L 5 speed manual transmission with 101, 000+ miles. I recently had an error code: P0171 System too lean bank code. I replaced my air/oil filter, spark plugs, ignition coils, and a damaged heater hose and hose clamps. I also replaced my mass air flow sensor. Not sure which one fixed it, but I no longer have an error code. Should I change my transmission fluid? It's never been done before. I am afraid to come across any issues if I don't.
The issue of old transmissions slipping after changing the fluid refers to automatics, NOT manuals. Yes, change it.
Thank you
Should I change my transmission fluid? It's never been done before.
This question is asked constantly so it answered in the FAQs
Getting a code with System too lean has nothing to do with replacing Transmission gear oil. But since it has 100k+ miles I would encourage you to change it to make the transmission last a really long time.
Not sure which one fixed it
If you diagnose instead of throw random parts, you can fix problems a lot faster, cheaper and more reliably.
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