Brice's NA V6 Build

I had it tuned fine before this all happened (LTFT's were a bit off I guess) and changing values in the fic6 doesn't do anything. I already tried changing the injector pulse width. I also tried subtracting fuel from the fuel table but it changes nothing.

 

Yeah I'll probably give it a try.

 

Sounds like a stuff maf clamp. But yours goes off of a 3 or 5 bar pressure sensor, does it not?

 

The engine ecu or the fic6?
The engine relies on the MAF for open loop airflow data and the fic 6 uses a 2,5bar map sensor I think.. But the MAF can affect the engine in closed loop as well so I dunno. Just to eliminate problems I did swap out my maf sensor for a spare I had but no change.

 

I was referring to the AEM. Sorry.

Have you test driven it yet?

 

No but I might try in just a little bit I wish I had an afr gauge to see what's going on with the stock stuff though...

 

You'll be able to tell if it feels like stock, or overly rich, instantly

 

Gadget at URD said any injector size over 420cc needed a standalone tuner. He couldn't make any piggyback tuner work. According to him, even with 420cc's you would still run pig rich and idle rough / rich.

I bet with those other injectors installed, your LT fuel trims were off the scale and your ST trims were swinging like Richard Simmons on viagra.

 

i've heard this as well.

But there are several folks on here now with running turbos with 500-650cc injectors..

 

STFT were ok actually, LTFT's were the ones that swung around. And the reason my fuel trims moved around so much is because I hadn't turned the o2 map properly except for at idle because I got lazy and kept putting it off. My ST fuel trims at idle were 0 to 3 with 650cc injectors at 14.4-15.0 AFR. They can be tuned to work just fine, and as I said before in a previous post, just ask @Clay_916 , He's having (from what I understand) fantastic results with his 650cc injectors and so is Vasinvictor with his 550cc ones. My issue is that I didn't tune it properly throughout the rpm range.

This whole "nothing above 420cc's" thing is only to do with piggy backs that DON'T intercept the injector signals like the MapECU3

At this point I'm betting on hardware failure not that my injectors are too big.

 

If you have time you might try reading through Joshua's build to find out his symptoms when his pump went out. I want to say it's in the first third of his total thread. Maybe I'm remembering wrong but I'm pretty sure he was running 9:1 constantly and swapping pumps fixed it for him. I'm not saying it makes sense or anything but that's just what happened.

Some thoughts:
Run back through your o2 skewing and get the offset numbers again. I've had to change mine a few times. If I had to guess I'd say the sensor is affected by ambient conditions. Doesn't really make sense but it worked.

What does you fuel map look like? As some have mentioned these injectors are fucking huge. Even with e85 (theoretically ~30% higher volume fuel demand) my highest value in my fuel table is -30. They shouldn't be too big but you'll need large negative values in your fuel map to adjust, like -60 at idle to -40 at peak MAP.

You can verify all the signals the fic sees using the software so it should be easy to spot any sensors giving bad signals such as a primary o2.

 

Im subtracting like 37.5% at idle, anymore and my ST fuel trims go waaaaaaay positive like 15-21 and the truck starts to stumble at idle. I think my highest value is like -20% but I'll check. And after all this Im gonna redo my offset map for the narrowband since I'm rich at higher loads, like -21 in overdrive, but idle trims are pretty good so I'll probably leave those alone.
Also I forgot to check the o2 voltage on the aem, I'll do that.

 

Those fuel values are probably good then.

 

That is old info still. My Map-Ecu 2 did 550's.

Pretty sure they cap out there or a around 600 something. Primarily due to trying to pull fuel, in the idle cells. The ecu only can so much. Due to the way most injectors flow based on voltage.

Were they Injector Dynamics injectors, they would probably work, while being a 750ccm +. Since in the low voltage area, they flow a little, and voltage has to be added to just them to flow enough. Whereas older technology, just dumps fuel, and you have to scale it back.

 

Alright so my fuel pressure is 50psi when it's supposed to be 43.5, which would explain the rich condition. I never got it into boost when it failed but had I bet AFRs would have cleaned up when I had over 7psi of boost. So I'm assuming its the pump or something is in the return line. I'm betting it's the pump. I'm thinking I can just buy another aem pump and be ok.

In other news my coilover/strut bushings are literally gone so new coilovers are on my to do list, any suggestions?
My upper ball joints are also ripped open, probably time to replace those.
Most of my bushings are shot come to think of it...Maybe it's time for a front suspension rebuild

 

ADS coilovers
SPC Light racing UCAs if you want longetvity..any other brand for cool guy points i guess.

 

Supposed to be 43psi according to Toyota or AEM? If the fuel pressure us steady, your pump is good. Putting in a higher flow pump will increase fuel pressure. Either way, an error of 7 psi seams a bit trivial.

I think we can look past the pump and retry the tune. If that doesn't work, I would suggest new and smaller injectors.

 

A higher pressure pump should not increase fuel pressure. Unless there are strange line issues. Such as a too small of a port opening on the return, somewhere in the tank. Also it could be a failing FPR, with a stuck diaphragm, were it boost referenced, and over powered the aged small OEM diaphragm. Even happened on my larger Tomei diaphragm. Was running 9:1 N/A, near WOT. Just some things to consider.

The fuel pressure, with out being vacuum referenced, should be around 43.5 psi. That is the industry standard across a multitude of makes and models. Being that it has high idle vacuum, and isn't direct injection.

Either way, St Andrew is right about the tune. Check the hardware first, then inspect the tuning device, and tune. Then you'll know if the AEM has failed for some reason, or if it is something with the tune.

Could you revert to the stock ecu, that would really make trouble shooting easy. I think you are back on the stock one though?

 

Didn't know that, but it would have to be referenced against the manifold pressure, right? Was this reading done at a warm idle or startup?

Hesitant to say is the regulator as it has a reputation for being very reliable. When I ask for recommendations for an aftermarket, I got a pretty strong recommendation on customtacos.com to keep the stock one in place.

I think you hit the nail on the head with the ecu voltage signal and injectors a few pages back. I think that was the issue Gadget referred to when he recommended nothing over 420cc with stock ecu. But he only tune with the MAP ECU 3 which didn't have injector pulse width adjustment so I'm surprised we are having this much issues on these injectors unless something is wrong with the tune. I still think they are too big but it should be able to get then drivable.

 

Let's also not rule out the possibility of the injectors as well. Those can be tested outside of the vehicle too. They could all or partially stopped flowing properly. As in more flow per volt than originally intended.

Start at about 8 minutes. Clearly not a precise instrument of measurement, but still good enough to determine if they are all flowing the same amount per time.

https://youtu.be/pmhmIi028-s