Ugh, the frustration continues. It's now doing the stalling/ hesitation from a stop when the car is running the engine too. So it doesn't matter if I'm accelerating from a stop while the engine is running or if it's on auto stop.

It is still definitely MUCH more prominent with the stalling/hesitation when the AC is running. The electric AC compressor is run by the HV batteries at all time from what I understand. Trying to think of how that is related t the problem. The GM tech did say that the U0073 code I discussed on the last page was labeled as "AC compressor control module" so it may be a related issue?

 

The guys you went to to look into the vehicle, do they have the GM Tech 2 or the GM MDI scan tools?

If you can get it into this stumble/clunky mode of operation and get Snap Shot battery data you can look for individual bad HV modules.

That battery is made up of 40 modules. There are 20 volt meter sensors in the HV pack. The GM scan tool can read ALL 20 at same time. Prius uses exact same cells. See Ebay listing for a great set of pictures of what is inside.

http://www.ebay.com/itm/KM503169-04-09-TOYOTA-PRIUS-BATTERY-CELL-7-2V-TESTED-7-4V-OEM-/181775572690?fits=Model%3APrius&hash=item2a52ab1ed2&vxp=mtr

If you look at the individual aluminum and gray plastic module... you can see the six ( 6 ) individual sub-cells. Prius uses 34 of these six sub-cell modules. GM uses 40. So 240 sub-cells. All wired in series. So if just one goes... it's done.

By narrowing down the PAIR of modules using a GM scan tool, you could buy a good Prius cell here shown on Ebay.

 

Ok last post is if it is battery. The GM scan tool Snap Shot function also works on transmission, engine, and hybrid computers. However one-at-a-time.

So the more repeatable the issue, the faster the scan tool and a good tech can find the problem.

Aux pump issues will cause a clutch to slip and then maybe grab. Hesitate followed by clunk.

So a Snap Shot during the "event" from HV battery, and at least hybrid computers will go a long way toward finding this.

 

No they did not have the proper GM diagnostic tools that they said they needed. They mostly wok on Toyotas and claimed it didn't make much sense for them to invest in the GM equipment...too bad. The hybrid tech at GM did say he was able to monitor the temperatures of each cell in the battery and that one was slightly hotter than the others. But that is all he said about monitoring the battery.

 

Could a bad aux pump cause the clutch to slip, resulting in the engine stalling?

 

If a clutch slip causes a "shut-down" there will be a friction element slip code. Yours appears to be more battery drop out related.


if it is the HV battery, voltage will drop out when large amoounts of amps are required.

The GM Tech 2 and newer MDI based scan tool can monitor and record so much more than just the 5 temperature sensors.

And again, every "P" code sets a Freeze Frame with a pre-programmed set of parameters like a "Black-Box" flight recorder. It's too bad that so many first CLEAR codes before doing any analysis.

Yours keeps setting the 2? P0BBD and P061B? Those are telling. The data that the dealer is ignoring has the rest of the evidence.

 

Ah ok, thanks for the clarification. This is the first time I have had the codes read, so I'm not sure of the they would come back if cleared. From our discussion I'm beggining to feel like the tech wasn't fully using the abilities of the scan tool he had at his disposal. We had in depth conversation about all this and what he did, he never mentioned a lot of what your talking about.

 

That is the problem with the "system". Techs are paid by operation code on flat rate.

The book time to REPLACE a part. So diagnostics and analysis are NOT stressed.

That's why I'm not Mr. Goodwrench anymore.

That said it looks like HV battery more and more. I would suggest calling dealers in a 50 mile radius until you find one that will do the battery for $3k total.

 

Hopefully your dealer is a hybrid servicing dealer. Read ELR service in their website. If they do then have them get all the codes not just the battery which can be a false positive.

 

Thanks for the help so far guys. Today Im replacing the spark plugs/wires air filter and cleaning the throttle body as Ive noticed they are all in pretty bad shape... doubtful this will resolve the issue but its needed maintenance.

Im tempted to bring it to a different dealership that may have a better hybrid tech, but will be reluctant to pay another $230 diagnostic fee to do so. Im not sure where to go from here. Called GM customer care who opened a case and is going to contact the dealership and ask if they will contribute to the cost seeing as how it is barely past the 100,000 mile warranty, but likely nothing will come of that.

I just really don't want to pay for the new battery and have it not fix the issue.