MPG increase due to new plugs and 12v battery

Have you changed out the HV battery yet? Or do you use the prolong device.
I have a 2005 and my Prius started exhibiting the symptoms of a failing hv battery at 170,000 miles or so.
I used the rebuild kit that newpriusbatteries.com sells and my
mileage jumped from the mid 20 mpg that I’ve been getting the past year to high 30’s. But I’m still not back to the high 40 to low 50 mpg I got when it was new. Ive started getting check engines that come and go with the errors showing that my cat is failing.
I’m wondering if the cat back pressure is causing some of the lower mpgs still. I should know
In a few weeks.
I did change out the injectors recently
and the idle is back to smooth as it was new. I’ve been using techron regularly but it finally couldn’t fix the stumble in the idle that it had developed. It still runs amazingly well for a car that’s almost 15 years old.

 

I haven’t changed out the hv battery, but thinking that time is coming. I changed the cat about a month ago and it made a huge difference. I just changed out the a/c blower and I need to replace the 12v soon. I think the shocks/struts are next. She is burning about 3/4 qt oil every 800-1000 mi. I’d love to get another 100,000-150,000 if I can. Its the oil piston rings that are the problem..

How was it using the rebuild kit?

 

I’m disabled so I paid my mechanic to do it for me. Total out of pocket was $1975. So about what I could get a new battery installed from the local Houston hybrids. Their battery prices from the dealer dropped about the same time I bought my kit.

You might want to try the BG oil flush products it might help with your oil problem, if you can afford it they have an powered engine flush process that’s $500 or so that really scrubs everything out. But the regular flush really cleaned out my engine but I’m not burning much oil. I’ve also had them install an oil separator can on my pvc to help keep the intake clean.
I put in the TRD shocks and springs years ago and they are holding up fine. Good luck, I’m hoping for 300,000 on mine without any major problems that will take another 10-15 years as I don’t drive as much anymore.

 

A lot of testing has shown that the transmission fluid should be changed at 60,000 or less. I send mine off for testing and it’s starts to get pretty funky by then it’s rated at 100,000 + but I wouldn’t push it that far.

 

I just ordered the BG EPR and the MOA to give it a go. I had used Marvel Mystery Oil and Seafoam spray through the air intake. Helped a lot, but she’s still burning oil. Everything is worth a try! Gotta get the oil rings clean.

I’m really hoping my hybrid battery pack holds on. I just replaced the catalytic converter.. that was a pretty penny.. :-/