How old is the 12volt battery?

MC-10154570-9999.pdf (nhtsa.gov)



do you have any U xxxx codes?


most people all ready chipped their tahoes with AS disable and AFM disable chips by now...



just get a AFM/AS disabler performace chip
100% you will not see a loss in MPG with them disabled


I'm still netting 20.9 in M4 100% ice on 91 octane (I have not gotten my Performance chip yet) with a 2009 battery..(according to the s/n on the battery)

I have to get a used one from out of state because it's illegal in california apparently.. from a private seller(they don't care)


mpg is all about how you drive anyways....

 

Check your throttle body to see if it is gummed up with gunk. That could be causing your idling issues. Clean your Mass Air Flow sensor with special MAF cleaner as well. You should be able to find that at any autoparts store.

 

I had the air box tube off so i could spray it with either, i think that was the issue, i also forgot to install the safty plug before recharging last week. i am recharging now and will figure this thing out today hopefully. maybe get a greenbean replacement battery if it all works out.

 

12 volt is new, no u codes last week no codes at all last week. hv battery is charging now will know shortly. Where do you get the amf/as disabler chip Tahoe_08

 

15 starts ice runs a bout 10 to 30 seconds each time. hear a klunk from trans and she dies and will not re-start until you clear the p0700. no other codes, voltage was at 325 at attempt 1 and after 15 starts 249/251. recharging now. I will put a transmission in it this weekend I guess.

 

That seems awfully low for the battery after 15 starts, but even with a recharged battery, something else is causing the problems. The p0700 code should be accompanied by other codes. The P0700 is just saying the Transmission Control Module requested "Check Engine" light illumination. I'd try to figure out what other codes there are before replacing the transmission.

While the ICE is running, try shifting to Neutral to see if the ICE stays running.

 

Jamie, i tried shifting into gear and neutral leached forward while going into drive and backward in reverse. It would not attempt to start in neutral. I picked up a transmission today from a parts yard for 800 was running and driving unit hit on all four corners. i will install it Thursday, I can get the battery for 900 if i need it. i checked the battery today for voltage loss and it was no volt loss over 28 hours i will update on Saturday. Thank you for all your thoughts and help

 

jamie, no other codes in any other modules besides radio

 

Update truck is on the rack. Almost completely confident that its in the transmission. my question is what is the cylinder that mounts to the front of the trans near the bell housing. has a fluid in and out input and a electrical connection going to the bottom of the fuse box. As of todays research i have all the trans codes and a couple more for brakes and power steering.. r&R ing the trans tomorrow. 311 volts at beginning of todays diagnoses and 4 starts later is 304 volts at end.

 

That is the Aux Transmission Fluid Pump. It should be pumping trans fluid when the ICE is off, to maintain pressure inside the transmission during Auto-Stop. When the ICE kicks back on, the Aux Fluid Pump stops.