Battery Corrosion, Traction Control, Motor Lagging, ABS...

I had an account here before but for some reason I can't seem to find or resurrect that old account. I've worked on a few other prius for myself and for a couple friends.

I bought a project, for the right price, but a project nonetheless.

2008 Prius with 177K miles. When I first bought the car the dash didn't work but I had no idea there were so many other issues with this car. I checked it for codes and it had none, but it has sat with a dead 12v battery and they could have been cleared, through all this and about a month of driving it has not thrown one code and there is nothing pending. Except when it Christmas treed the dash and I found a corroded battery.

When it gets to around 30 it seems to shudder when it's trying to switch from electric to gas(ICE) only. Sometimes it drives just great with no issues and other times it feels like the traction control is trying to trigger or the ICE isn't coming on quick enough or it's running rough.

When I bought it there was a set of plugs on the floorboard and a new air filter. When I was installing those I noticed that someone had installed a Mass air flow sensor. So it's obvious that there were issues that someone was already trying to figure out.

It seemed to like the new parts but was still acting weird with the shuddering and it also had a set of miss matched take off tires, all the same size just all different brands. So I was hoping that maybe the ABS or traction control wasn't liking the used tires and put a new set on... it still runs great at times and then has issues.

Last week it gave me the Christmas tree of death.... I said great it's probably just been the battery all along. It has a "rebuilt" battery with 10,000 miles on it. I pulled the battery and it was covered with corrosion. All modules were within .2 volts of each other and they all read around 7.8 volts. I cleaned and reinstalled the battery, I forced a full charge and it's still doing the shuddering thing.

At times it seems like it is slipping like a regular automatic transmission would, but anyone that has driven a Prius on snow... it also sometimes feels like the traction control is triggering but not showing the warning on the dash. After I cleaned the traction battery and was really accelerating hard, it was doing the shuddering thing again, only this one time the traction control warning light came on so I'm wondering if it's a wheel sensor issue and this was the only time it's triggered the warning light.

I'm kind of at a loss. Transmission? The fluid was dark but no chunks and not very metallic looking. ICE issues? The oil was clean and after an oil change and about 1200 miles it's still pretty clean for a Prius with 177K miles.

 

That one of the problems, this care has too many problems to just put a finger on the one issue.

I ordered techstream with cable from amazon, first one came with a cracked disk and I tried to find a downloadable version while amazon sent a replacement... all the online versions or techstream had viruses as did the second item from amazon.

I have a OBD2 tool and I have used it on other prius and this care is showing no codes or pending codes save for when it through up the christmas tree. since I have cleaned up the battery it is almost half full or better, before I cleaned the battery it would go down to one or two bars.

I am in Southern California near palm springs.

 

Shuddering feels more like it is cutting power while running. It will actually shake you back and forth, though slightly, in the seat. It feels a lot like when the traction control is triggered and it cuts power, like when you are on ice.

 

Wow this form used to be much more active. Where is everybody gone?

 

Thanks for all the replies. I had to go out of town for a couple weeks but your suggestions will help when I return.