P0731 code after re-gearing

[Twisted289]

I had my 14 JKU Re-Geared from 3:21's to 4:11's, Now I have a P0731 code. RPM's @60 are 4000. I'm hoping i need to have pcm re-flashed or did I just throw $1600 away?

 

[BLACKJKU]

Did you reprogram when you changed the gears so your speedometer is reading right?

 

[Twisted289]

No, I was thinking he should have. My speedo only seems off by 1 to 2 mph, my rpm's are really high...

 

[BLACKJKU]

Your RPM's on the highway will be higher now with the jump you made in gears, if you put bigger tires on you'll lower the RPM's.

 

[Twisted289]

Your RPM's on the highway will be higher now with the jump you made in gears, if you put bigger tires on you'll lower the RPM's.

Its supposed to be 2400 rpm @70mph with 33' tires. It's 4000rpm @ 60. Something is not right.

 

[BLACKJKU]

Find a GPS and verify your speedometer is reading correctly.

 

[Twisted289]

Find a GPS and verify your speedometer is reading correctly.

My speedo only seems off by 1 to 2 mph

 

[Hooperdog]

you need a procal or equivalent to update the ecu for the gears. what size tires?

 

[Anybodyhome]

Its supposed to be 2400 rpm @70mph with 33' tires. It's 4000rpm @ 60. Something is not right.

Is it actually running at 4000 or is the tach just displaying 4000?

 

[Twisted289]

you need a procal or equivalent to update the ecu for the gears. what size tires?

33" I bought a Superchips Flashpaq F5. Problem solved. As soon as I changed the gear ratio it was back to normal.

 

[Twisted289]

Update: I bought a Superchips Flashpaq F5. Problem solved. As soon as I changed the gear ratio it was back to normal.

 

[Hooperdog]

Update: I bought a Superchips Flashpaq F5. Problem solved. As soon as I changed the gear ratio it was back to normal.

Same one I have, works great.