Okay so I've posted in the past about the car stuck at 5k 4th gear and not shifting into 5th unless in slap mode. Well I forgot to mention that the check engine light will blink at that 4-5k too. My amp also started acting up going into protection mode. Found out that it can be a cause of not enough power causing the amp to go into protection and the transmission to go into a fail safe mode. I got the alternator and battery checked and everything came out good. I am do for a tuneup because I got a random misfire code and 2,4,5,6 so I know sparkplugs and a coil pack need to be changed. My question is could me not doing my tuneup cause this trans to go into a fail safe?

 

Your AMP has a protection Mode?
Are all the ground wires good? clean and tight? there are several in the engine compartment and to trans

The ECU will limit rpm to 3000 when it suspects a major problem
Never heard of trans protective mode
In P or N the rpm is limited to 5000

what are you doing driving/ shifting at 5k rpm with known cyl misfire codes?? those are likely 1 or 2 failing coils, and will it need spark plugs by now too
use only the correct NGK $8 each ones

Looked at the atf level -per owner book fluid temp - Level should be between the dots- not at either end- between them
Fluid looks red and smells like ATF? or smells like burnt toast and is blackish-brownish?

 

All fluid levels are fine smell fine look fine. I'm big into system everything's ran correctly and amp is fine. The transmission and amp started acting up at the same time. I can drive it d5 and it still doesn't shift so I'm not sure I thought maybe its electrical

 

It drives fine in 1-3 but on highway around 80 mph it'll get up to 4-5k and not shift in d5 mode. It just started it randomly same time with the amp so I'm not sure what's going on.

 

ck ground for old sub amp- in trunk- known to cause problems when systems are changed

try driving with less throttle so it shifts around 2500-3000 rpm