Revving too high before it will shift...

[tybardy]

I will take it to a mechanic in the morning. Thanks for the help.

keep us all posted man, i am interested to see what develops

 

[Rollin Thunder]

keep us all posted man, i am interested to see what develops

I think somthing is wrong with his truck. IDK I could be wrong. lol.

 

[tybardy]

yes but seemingly large problems can develope from very small and easy fixes, like sensors or computer work

 

[9CZ71Denali]

Mechanic is on vacation until tomorrow, but he will look at it bright and early.

Today, on my way down there I the CEL came back on and gave me 2 P0420 codes and later on while accelerating, I lost all power and the CEL flashed with P0300. I am starting to think it's a bad cat or O2 sensor...

 

[tybardy]

it sounds very likely that you are looking at something like a sensor or even a control module issue... for your sake, i hope so! just be easy on her because driving with a sensor gone bad can cause your motor to try and "fix" itself, which will in turn end up doing a lot of damage

 

[9CZ71Denali]

O2 sensors, knock sensors, intake manifold gasket all good. New MAF & fuel filter, throttle body cleaning and seafoam fix nothing... Looks to be the cat, will have them done friday.

How bad would it be to just hammer them out?

 

[tybardy]

Who said it was the cats? as far knocking them out, i havent done that since i had my 82 GMC and that was easy as pie, pull it off and smash the shit out of the interior media with a flat head till its empty.

i dont understand why the cat would be causing all those problems...

 

[Yukonxl]

Mine just started with high rev from 2-3 gear, but it was after I had my trans oil flushed and changed. The mechanic thinks it is a vacuum thing and that the oil change loosened up something. I am taking it in next week, I guess we will see.

 

[9CZ71Denali]

Had both cats and banks replaced, runs like new now!

Thanks again for the help.

 

[tybardy]

good to hear... do you really have a Z71 Denali? i was unaware they made such a thing? you got pics?