Part throttle in boost afr's

So ive had my tacoma a little over a year now and have recently added the magnuson supercharger and flashed the TRD tune instead of the bully dog tune (I work at Toyota and used to be a Toyota tech) I love the power still on stock air intake and just have the TRD exhaust im sure it doesnt help any power wise haha. One thing i have noticed is under part throttle esp climbing a hill it will build 2-4 psi of boost and wont change AFR it will stay around 14.3 its not until I add more throttle that it kicks down and drops into open loop and goes 10.0 afr is this just the nature of the beast and I shouldnt be concerned? My wife drives the truck sometimes and she def isnt going to be paying attention to these things and I want to make sure im not putting the truck in any danger so just looking for some input from you guys with more experience then me with boosted applications?

 

The TRD Tune wont start enrichment until you eclipse 75deg of throttle angle or if you reach certain exhaust component temperatures where the tune will apply various amounts of additional fuel dependent upon RPM/Load. High RPM/Load can add up to 50% additional fuel over base calculations.

The TRD tune has proven quite reliable, but leaves a lot of room for improvement as well. I wouldn't stress.

 

Part throttle enrichment has and always will be an issue with these trucks. I don't start to see any real change to my AFRs until I go WOT, if I'm at part throttle I have to maintain it for a good 4 or 5 seconds before the AFRs will adjust and richen some. It's a common issue.

I think for the 2nd gen trucks, the URD UCON tuner is supposed to help with that. On 1st gens like mine, we have to use methanol injection or the 7th injector kit to help. I have the 7th but to be honest it's still an issue.

 

Your best bet is to use HPTuners to actually reflash the stock ECU to eliminate the part throttle fueling issues, address throttle response, timing maps, VVTi settings, transmission shift points and pressures among many others.

https://www.tacomaworld.com/threads/hp-tuners-for-2005-2015.600793/

 

This is good info to have, I see HP Tuners in my future for sure but with no idea how to use it havent rushed out to pick it up just yet, Also is anyone else supercharger super loud at idle, kind of sounds like marbles in a can?

 

Usually that's a sign of it needing a rebuild. They all make noise at idle but if it's obnoxious it might be time to look into it. How many miles are on it? TRD states they should be good for 100k or so before a rebuild is needed, depending on how hard they're driven. Change the oil every 30k or so?

 

Hummm well it has about 200 miles on it haha I bought it new from gadget maybe Im just used to how quiet it was stock and Im being super sensitive since I did a bunch of work, Im sure you guys are the same way right after a big job!

 

Oh yeah I'm sure that's just the normal sound then haha. You can look up "supercharger needs rebuild" on Youtube and see/hear some videos of what a bad one sounds like, it's pretty obnoxious.

 

With the ucon I would be in 3 pounds of boost or less and still at 14.7 afr’s with moderate throttle. When the boost went over that it would drop in the 11’s.

 

My trd tune and my ovtune does this also.

Join us supercharged junkies here https://www.tacomaworld.com/threads...4-0-supercharger-tips-tricks-and-mods.518932/

 

AFR's at 10 -11 range in boost are safely rich, but you wouldn't want them much leaner than 11.5 or so if you're in the 10psi+ range for boost. What kind of hp increase do you get on the 4L with the TRD setup? I've thought about adding this to my truck, my vehicle previous to my Taco was supercharged and the power was intoxicating. I was getting 225 whp @ 15 psi from a 1.8 liter 4 cyl (stock was about 106) and it was a relatively mild tune.