i looked under my drivers seat and saw a vent i assume that is a A/C output vent .. that will adjust the settings to the floor


on the map sensor it's under the engine beauty cover easy as 1-2-3.. to change
it's an Easy DIY change you just need a flat head screw driver to take the clip off...

just ground your self to the body first to prevent static discharge
this is the one I bought much cheaper then getting it from autozonethey wanted over $80https://www.ebay.com/itm/09359409-OE...72.m2749.l2649


Verify the reading before replacement or buying the replacement...

the map sensor should read 27KPa to 30KPa idle at normal operating temperature
should be over 40 KPa while driving. at normal operating temperature


also check and see if the sensor is fouled with oil it will give false readings to the engine

Make sure the connection is tight sometimes those map sensors come loose.. (the connector) At lest mine was not connected all the way..


Mass Air Flow sensor, sensor inspection and cleaning

buy a can of MAF sensor cleaner(MAKE SURE it's MAF sensor cleaner)

unscrew the two flat heads carefully remove them inspect maf

look for damage on the honey cone structure cracks or breaks in the honey .

.look for broken wire or frayed wire on the MAF there is two wires

clean using cleaner

Most important step is to LET DRY for 15 min..
.reinstall carefully


disconnection of the battery is not required(it could damage the Air Conditioner actuators causing them to do a full sweep)

ground your self before so as not to damage the electronics with static electricity.

.this is very low voltage only 5 volts..

remember to remove all metal objects from your hands such as watches or rings.

.ALSO when looking at the map sensor

THERE IS A VERY sharp edge on the engine beauty cover so be very careful

I all ready got cut from it.....Another question does it do it in M gear?

 

Answer: transmission pump

Story: Just left the car for two months with the Chevy dealer. They tried to talk me into about $6k worth of repairs where they couldn't recreate the issue but wanted to replace the Body Control Module, hybrid battery, and other items.

Took it to Ray's Auto Repair in Los Angeles (off Colorado blvd) and left with him for a few weeks. He drove it around, put real miles on the car, was able to recreate the issue, spent more time diagnosing it to make sure, then landed on the transmission pump. So far, it's been a few weeks and no issues. Will update.

 

shutter is caused by something else the bump from autostop resume is the aux transmission pump
the shutter with low engine speed was caused by a clogged air filter (my was clogged with fine powered dirt) also the IAT was broken (off by 15F)

I put a a oem filter and new oem MAF/IAT.

how much id he charge to put the new Transmission aux pump? might want to get mine done