I miss the "back to the future" electric sounds the hybrid makes compared to my 15 platinum.

 

Alright I need some help have a 2008 GMC Yukon hybrid replaced motor with rebuilt engine same motor just rebuilt just got it put in and now the truck will not start no codes are present battery is fully charged cranks for one second and and fully start kind of lost here need help just spent $3,800 to get the engine rebuilt disappointed

 

sounds like your key is no longer programmed in the computer ... you may need to simply reprogram the key

 

Power getting to fuel pump? How is the oil pressure for the few seconds it runs (I think you are saying it runs for a few moments)? When motor was rebuilt was oil pump re-primed afterwards? If zero oil pressure some GM vehicles shut down to mitigate damage. Are you sure it's not just going into auto stop mode?

If it were key coding, the security light should be blinking. I've had ECU/battery unplugged in storage for winter and have not had security settings issues on other GM vehicles. But it is worth looking into.

 

The engine does spin?


For 1 second or up to 8?


Did you purge the air out of the fuel rail? That vehicle has a "one way" fuel system.


You will only get so many cranks before the Hybrid Battery goes low and that is a real pain in the ***

 

I think I'm having this issue as well. 2008 Tahoe will not start with "Service Hybrid System" on dash. Brand new 12V battery and a reman'd hybrid battery that is approx. 5 mos old. No air in the fuel rail.

Am I out of self-diagnostic options and just need to be towed?

I am >170k and way out of warranty.

 

Reading the codes BEFORE clearing them will provide valuable clues.

 

Thank you Keith,
no I did not do the discharge test I just squeaked out the money and replaced the Hv battery. It ended up flashing a message “service hybrid system” the day after I posted the first question. Battery volt message center says I’m on 12v when the car is off but key is turned on and then reads 15v when the car is on. So I assume it’s safe to say the 12v is fine? I am
going to purchase the diagnostic reader that the other reply suggested just for future. I really appreciate you all helping me out with this.

 

What stealership was this? $2k for that inverter module is a good deal.