Running rich

[Matt83]

Hi all. I have a 2015 Viper LTX with an MPI trail turbo and no other motor upgrades. The sled ran good all season with my average fuel mileage being in the 13-14 mpg range. Then at the end of the season, my final ride the sled started to backfire whenever I let off the throttle and my mileage went down to about 8 mpg. Nothing was changed on the sled at all. The only difference was the outside temp, all through the winter it was -10C or colder, the last ride was +1C. I've talked to my dealer about it and he said there have been reports of other Vipers doing this that are boosted and N/A but had no suggestions for a fix. Hopefully someone here has an idea! Thanks guys! Also great site, I've learned a ton of great stuff since I started poking around here a few months back.

 

[Dinner]

Not sure if it's the same as the apex's..but backfiring on deceleration on apex's was caused by leaking exhaust monifold donuts. Others will chime in though, I could be out to lunch!

 

[tator]

when my header cracked i had increased fuel consumption and loss of power. but still built boost, just not as much or as quick.

 

[Matt83]

when my header cracked i had increased fuel consumption and loss of power. but still built boost, just not as much or as quick.

Is there a common place for the headers to crack?

 

[cannondale27]

Here from FAQ
http://www.ty4stroke.com/threads/he...one-with-header-problems.129862/#post-1163559

Makes sense. Air leak is sensed so more fuel is added.

 

[Matt83]

Thanks tator and cannondale. I read through the thread and will check my header when I get a chance.