I want to say the car has been boosted for about 2 months now, and has a stalling issue. I talked to my tuner about it and he suspects it's because of where the maf sensor is placed (blow through setup). The car shuts off more when I use the a/c, so havent been using that lately. The issue also arises more when I go somewhere for a while and then come back to the car when its still warm. Stop and go traffic is kind of an issue too.

My tuner also said if I relocate the maf sensor and make it a non blow through setup may fix the issue becaus he thinks there is too much turbulence because of the location. I was also reading up and going to try cleaning the maf and the throttlebody. Usually when I drive and go back into neutral the idle is a bit rough and bounces. The car isn't throwing any codes though.

Any help would be greatly appreciated on what else I should check or may be the problem.

Current setup
Boostflow EL manifold
Garrett 60 Trim 82ar Housing
2.5" downpipe/s-pipe combo with Wideband 02 boss welded in
Synapse Blowoff valve with anti-stall kit
Tial 38mm mvs wastegate(15lb spring) and 11.5 psi spring installed
ptuning 700cc Injectors
Aem fic

 

Pic of MAF location?

 

that doesnt really make sense. i (as well as alot if ppl on here) have setups with a blow thru setup and have no stalling issues. i personally dont think it may be that. i find it to be better actually. what r ur afr's like at idle? i say if its really lean, it may be a vaccum leak. but like paul said...pics would def help out a bit more.

 

i dont understand how thats possible unless your maf is RIGHT against your BoV. if it isnt far enough away it will get false readings.

 

If it is in a bend, too close to a bend or there is something like that flexible dryer hose before the MAF, all of these can cause turbulence.

 

afr's at idle is usually around 14.9-15.2
When i first start up the car in the morning I let it warm up, I drive it and it is fine most of the time.Its more of when I drive and then start to come to a stop,when in neutral the rpm's start to bounce a little and also in stop and go traffic. Its also more of lets say I drive the car then have to run errands, restart the car, let it warm up and then it starts to have the issue. The ac being on also causes it to cut off more.

Normal idle is about 800 I want to say, but when i drive and slow down to stop the needle likes to bounce around 500-1k.My tune is set to run a little rich, but this is happening even when I'm not in boost. I'm planning on getting it retuned, but had to fix some issues first, this is one of those issues.

Now the issue I'm describing with the needle bouncing,could that be because of a sticky throttle body? I really want to sort this out and enjoy the car and actually drive drive it. More help please

The pic is bad with the strut bar in the way, sorry.



General guess on how far it is from the bov is about 2-3 inches I want to say.

 

your tune is the issue sounds like... You can upload a copy of map if you would like us to look at it?

 

i agree w mike on that one. placement of everything seems to look ok. altho general rule of thumb is that the bov and maf need to be around 6" away from each other.

 

Hmm ok a retune may be needed then as you all say. I'll have to check back with him because it isn't throwing any codes. I don't have any way to upload the tune right now on here so its I know its kind of a guess and solve issue right now, but if you all are leaning towards the tune more I'm gonna go with that for now because its the cheaper than getting new pipe made. I'l give an update and if the problem still occurs after a retune.

I'll try to get the tuner to give me a copy of the map so you all can look at it too.

 

what engine management r u runnin?

 

he sad the AEM Fic

 

haha yeah I'm running the fic for management. I'm going to try and a get a video up of the issue later.

 

welp cleaned the throttle body and the maf sensor, issue still there, retune on saturday

 

maf is super close for sure.

 

im gonna get a retune and see if it fixes the issue. Hoping he can get to it saturday. If the issue still stays then i'll just cut out that piece of piping and fab up an intake pipe for the kit if you all agree with it being too close to the throttle body.

 

Bouncing idle... sounds like erratic fuel trim changes. A retune wont fix an issue. MAF sensor seems a bit close to throttle body bend. If it isn't that, primary O2 sounds flakey.

 

Wouldn't a bad primary O2 throw a code though? I'm not getting and cel's

 

usually a code will pop up, but sometimes it won't if it intermittently functions. If your car has over say 80k on the odo, you should figure a new Toyota primary O2 sensor anyways IMO. If it were me, I woundnt spend $ tuning knowing the tune revolves around a old sensor.... because you may replace that sensor soon, and guess what? More $ for a retune. If you were on a emanage, no big deal because you can tune without the O2 even connected. But the FIC depends on it.

A quick test you can do, disconnect your primary O2 sensor when your idle starts bouncing. If it stops bouncing then you know it was the O2. If not, blame the maf.

 

fic doesnt depend on the primary o2 sensor, you can tune the fic without a primary if you wanted to (im doing that right now to try and trouble shoot some harness problems). I wished it ran off its own wideband and "self corrected" so to speak but of course that would add prolly 300-400 to the price tag.
I agree though with blownxa on replacing the primary anyways at that mileage (exp if part of those were boosted miles).
you have any idea of what your fuel trims are? also did you notice the o-ring around the maf sensor (was it pinched, cut, or even there)? have you done a boost leak test? Im thinking this could be tune though, you said you replaced the injectors with smaller ones and it sorta helped and that the problem is worse with a/c on right?

regardless making sure the system is free of leaks and sensors are fine will aid in a good tune.

ps if your feeling froggy you could unplug the fic and plug in your ecu, throw on the stock injectors, and watch your afr's and fuel trims. if fuel trims are still out of wack or afr's are all over the place (bouncing even) then you have just ruled out tune.

 

damn if it close to 80k.... The car hasn't even hit 35,000 yet. The injectors are 700's. When I checked the maf when I cleaned it the gasket looked fine. I really don't know my fuel trims . Even when I got it tuned the first time I was out of town. I told my tuner about the issue and if he has a opening this week he said he'll work trimming the fuel out.

Crush I didn't replace the injectors with smaller ones. The issue is there more with ac on. When I worked on it yesturday(throttle body and maf clean) the idle was fine. AFR reading was at 15.2, little bit of fluctuations from 14.8-15.2. After i test drove it the car was fine, but still opted to reset the ecu one more time. I did tghe whole disconnect the battery for so many minutes then let it sit and idle for 15. As i was pulling out of the driveway it cut off again while I was in reverse. The issue seems to arise more if the car has already been warmed up,ran for a while then shut off and restarted again. This time it only shut off once while reversing though. Driving it around the neighborhood i had no more hiccups from it.

I'll ask the tuner about doing a boost leak test when he has the car, School is starting back up for me this coming up week so the car is kind of on the backburner again smh.