03 Yukon - reduced engine power issue

[DonnieBrasco]

UPDATE...

So I'm waiting on a code reader to get here. Got under the hood today to check wiring in the TB and such. Went to crank it to just see how it's running and it won't crank. It barely turns over and then clicks. HOWEVER, the rest of my electrical is working. My phone charger works, power locks, the radio works (but the clock was reset).

Does this point to the alternator? Would the alternator go out while driving and cause reduced engine power?

 

[DonnieBrasco]

I'd also like to check any possible ground wires. But there are so damn many and I can't find a good resource showing where all of them are.

 

[DonnieBrasco]

Now the battery is dead. Completely dead. So I've got to charge it this weekend so I can pull the codes.

 

[01ssreda4]

You need to charge the battery, then check voltage while the engine runs. It should be 12.8 to mid 14s.

 

[DonnieBrasco]

You need to charge the battery, then check voltage while the engine runs. It should be 12.8 to mid 14s.

All over it in the morning! I'll be back with the codes tomorrow hopefully...

 

[Rocket Man]

Mine ended up being clogged cats. I could clear the codes and it would be OK until I mashed the throttle. Kept getting worse, threw lots of different codes but always went into reduced power mode.

 

[DonnieBrasco]

Can anyone make sense of how the dead battery factors into this situation?

 

[retiredsparky]

Well, as you have commented in a previous post, it could be a bad battery, bad alternator, bad grounds. After charging battery, drive to an auto parts store or auto repair facility and have the charging system checked. Discharged batteries most often are caused by the causes you mentioned.

 

[Zigger21]

Can anyone make sense of how the dead battery factors into this situation?

Electrical drain if your battery is dead in morning or your alternator maybe draining it. If you have a Fluke meter put it on inline DC and unhook your ground wire from your battery and put your mater in between the battery and the negative cable and if you have any amps on the fluke while there is nothing on in your vehicle.

 

[DonnieBrasco]

Well, as you have commented in a previous post, it could be a bad battery, bad alternator, bad grounds. After charging battery, drive to an auto parts store or auto repair facility and have the charging system checked. Discharged batteries most often are caused by the causes you mentioned.

Charged the battery and hooked up my scanner and no codes. And it cranked fine didn't even have a check engine light. This is weird...