how many miles? as you know hybrids have 8 year 100k miles warranty on hybrid components.

 

112000. 1600 on motor

Any help or guidance is greatly appreciated

 

$18000 ..it needs tires ..but that's iti think I've talked to the dealer that it's been to most of its services . Engine failed due to , at least I think from longer then recommended oil change in rebels anda failed lifter which he changed one not all as was re comended by dealer and then failed oil pump which was catastrophic to motor

 

Any updates as to what the actual cause was with you truck ? A little old on the original post but hopefully you still look or read the boards here

 

I am having the same issues with my 4wd Yukon. Did anyone scrounge up any definitive answers regarding the odd transmission issues/ hesitation?

 

What are the HV battery temperatures, voltages, and State Of Charge when the odd things happen?

The dealer scan tool can get those. Another poster here put pictures up of the HV battery air inlet pretty much obstructed by lint build up.

A hot battery will cause all sorts of odd behavior. The hybrid needs to put power in and take power out. If the battery is too hot from cooling obstruction, the amount of in-and-out power is greatly reduced.

This causes engine RPM flares and bad behavior.

I recomend looking at that air inlet screen on every 2 Mode wit hhigh miles.

 

my started experiencing this exact issue.. BEFORE any of this I had used the cruse control for the first time having it (YES it's switched off I only use on the freeway for BEST MPG)

from park to drive on a cold start
in the days leading up to this the SUV had been

acting weird like TPMS not working on one tire
unintended acceleration it REVVED to 1500 RPM SURGE before AUTO stop and started accelerating it went from 10mph in FIRST gear to 15MPH in second gear very quickly and unexpectedly.. then the engine shut off (Auto STOP)
THIS IS A MAJOR violation of 49 CFR Part 571 NHTSA
vehicle creep speed is limited to 10MPH and 2nd gear (etc..)is locked out unless the gas peddle is pressed....

(this part below happened the same day later on)



and When I wanted to ACCELERATE it just sat there and revved the engine AND nothing ... like it was about to go into sleep mode exactly when i pressed the accelerator.. and it just sat there and revved the engine to 1600rpm I almost got rear end by an impatient pickup truck driver...

85,800Miles

I had all ready cleaned out the battery air intake

today
I put the Transmission M4 mode and it started working fine and ran smoothly and shifted correctly (tow mode OFF but in M4)
like nothing was wrong I suspect a computer glitch issue after 1 miles of driving i switched it back TO DRIVE and

it seemed normal
it coasted smoother, regeneration worked correctly , Auto Stop worked correctly etc...

built 01/2008



Normally AUTO stop does not have a surge it's typically "Auto start" Since it's a HIGH SPEED start to synchronize with the speed of the suv


There is NO start lag and the SUV fires up right away on cold and Auto Starts no lag..

 

T8 all those symptoms seem to point directly at the transmission auxiliary pump that is supposed to keep trans fluid pressure when the ICE is in autostop. There are several articles around the internet and from what i saw you will need to change both the pump and harness since the only available pump (as a new unit) is a +2010 design that has a different wiring connection.

 

looks like people have been getting scammed into buying new transmission pumps and new wires they don't really need(unless you have a code)

"it made it look like it was repaired from the new pump" but all they did was resit the battery cable after working on it..

turned out to be the Wire harness to the 12+vDC battery it's fully secured now reporting 14-15voltsDC
before it was reporting 11-13VDC



The cables were loose causing poor contact . loose enough to cause the battery to discharge to 11.9 volts


as you can see it's secured further down the battery post giving a tighter connection it was pretty dirty someone used a oil based battery protection
I bought CRC RED battery protector its not oil based....

the suv is working correctly even the Regenerative braking system works much better too... it has at lest 40% more stopping power then before.. cause the clutch is staying engaged like it should...

i still have friction issues that i need to deal with ..(squeaky brake pad in the rear)

..