Losing power uphill

your hybrid battery is probably getting weaker. how many miles on her?

 

Pre-ignition issue ? (Detonation?) Uphill's load the engine up. Timing issues/pre-ignition problems typically show up on hills first..

 

If you are getting pre-ignition, or pinking, you should try higher octane gas first. Use 91 (AKI or R+M/2) or higher. If you are often at significant elevation you can use lower than 91 (AKI or R+M/2). What octane rating are you using currently?

But in all likelihood, the regular mountain work has taken a toll on the HV battery. Be prepared to be replacing it in the near future.



* AKI or R+M/2 is used in USA.

 

How does your air filter look? Also, consider cleaning your MAF sensor. Yes, this could be another HV battery issue but don't forget to consider non-HV battery possibilities.

Paul

 

If there are no codes then it's probably not pre-ignition. At 300+K miles I would definitely look at the plugs, but plugs do not cause problems like this unless they completely fall apart. I would suspect bad gas if this came on suddenly. Consider draining it and refueling with known good stuff.

Wow! 300+K miles!

 

How much oil does it burn, has the catalytic converter ever been changed, i'm thinking plugged exhaust.

 

The HV battery is air cooled but the inverter has a water pump to cool it.

Is your inverter resevoir full and can you see movement in the tank?

 

So it seems you have an overheating inverter, from a failed inverter pump. That would explain the power loss

 

How fast does the display cycle between full bars and low bars, starting the engine? What’s your mpg been recently?

 

Hello, my car shows similar issues. Some key specs about the car and the situation

• 2007 Prius, with about 255K Miles
• Doesn't quickly accelerate without a "rattling" sound when I floor the pedal
• Loses power uphill, and barely maintains beyond 60MPH
• Same "rattling" sound when I put on Cruise Control
• Mentioned it to Dealership mechanic, who suggested Water Pump and Drive Belt, pre-diagnostic. Professional diagnostic would've been more $$
• Code shows Catalytic converter and misfiring.

Please help. Thanks !

 

How did you get the codes, if you declined the dealer diagnosis?

There may be other codes the code reader you used cannot see.

As a WAG, this does sound more like your HV (hybrid vehicle) battery getting very weak. In addition, the misfire could be related to that or could be a separate issue that cleaning the throttle body and MAF may fix. A poorly performing ICE can contribute P0420 (if that the code to which you are alluding).

If you can get the codes read and get all of them that have been set, we can give more specific advice.

 

I'm not aware of a way for a weak traction battery to cause engine misfiring. Misfires will usually be caused by the usual suspects. Codes about the catalytic converter might reflect the unburned fuel coming out in the exhaust after misfiring, but that unburned fuel can also do real damage to the cat converter, in which case just fixing the misfiring, while necessary, will not make the cat codes go away.

 

Your cats bad at minimum, possibly old traction battery also. If you need to go to the dealer or any mechanic to fix it you would be better off selling it. The only possible way to break even at this point in your cars life is if you can do the repairs yourself. If you cant then sell it.