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For context I just started getting interested in cars and I've decided to fix up a car that's been in my family for a while. It's an '04 Honda Civic Hybrid with a tranny that as been slipping for a while. I replaced the atf last week and it came out pretty dark/ near black with lots of particles/flakes in it(should I keep replacing it till it's clear? I've read that all the friction in the fluid might be keeping the tranny going if it's bad enough). I don't think my parents or sister who owned it ever replaced the atf and it was also low in fluid as well. Before the change the Check engine light was on, and the D light started blinking once every couple of months.
I finally got a code scanner on the car and it's showing P1891 and P0700 (amongst P1600, P0420 and P1433, but those don't seem to be related maybe? and are a whole other task to tackle). I've been looking all over and can't find a good way to diagnose the error codes and figure out what is actually wrong. Other than checking the grounds? and checking the TCM connection's(I haven't got to that point yet. Still trying to figure out where those are...).
The times I notice anything abnormal is when accelerating after stops. I usually nudge the accelerator till I feel a catch(basically like in a manual after releasing the clutch) otherwise the car will jerk. This doesn't happen always, but it is frequent(1 in 3 stops).
Thanks for the help.

 
Rep Power: 367

did you use the drain and refill method? there is a proper procedure for that, I think 5 times?
I would think this would be same for hybrids

 
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I only drained and refilled once last week. I'm planning on doing my second today and my third next week(I only drive about 50 mi a week). I didn't know civics was 5xs, i thought it was only a 3x flush. But I guess that would clean out all that gunk. I was concerned with continuing with the empty refill cycles though with all I've read about how you shouldn't change atf after it's gotten dark and chunky enough. Think I should continue since I've already emptied some of it?

 
Rep Power: 367

don't quote me on the number, I only had one for not long, Trade in 2004 or 2005 for a manual trans. If you checked honda recommended fluid change, and it was 3, it's fine

 
Rep Power: 367

checked - looks like it is a 3x

https://www.civicforums.com/forums/3...ml#post4798133

 
Rep Power: 367

also, the famous death code is this one: - the early cars had lots of failed trans, the reason we created a new section specifically for it in the forums

https://www.civicforums.com/forums/3...ml#post4798305