Gtt Running Rich/tune Advice

[MikeR34GTT]

Hello my favorite people (most of you anyway),

Finally upgraded my GTT with a catback system (Venom Cat with a 3.5 Xforce System) and ever since then, I've noticed alot of backfiring which isn't severe, just very consistent - more so when letting my foot off the accelerator, and I don't even have to be flogging it to get it to backfire, probably 2/5 times. Fuel economy is also a bit so so, it's not bad but I think I could improve it a little.

I've read into this a bit and most of the advice of read into suggest I'm just running rich and the general way around it is to get her tuned, BUT, I've been advised I cannot tune a stock R34 ECU?

Is there anything I can do to alleviate running rich/fuel economy also, like changing out the O2 sensor or running some injector cleaner through her?

If tune is the only way, can I opt for a Nistune Chip over an AVCR because $1,000 + tune to combat the RR seems a bit overkill and my modding path doesn't include an aftermarket ECU (was actually planning for Nistune anyway - she's my daily so I dont want to rape her with mods)

What do you reckon boys and girls?

Cheerio!

[Trex]

nistune will sort you out. a quick google will give you all the answers you need.

And backfiring on overrun isn't a bad thing, it can be tuned out if you don't like it.

[blind_elk]

Check the TPS. If it isn't indicating a "throttle closed" condition at no-throttle, then it will not be shutting down the injectors during back off and gear changes.