Really!?

[chuckmuska2005]

I just installed a NEO in my brother's supra and went through the initialize setup and did the sensor check, started the car and it runs rich with no engine codes. wide band reads 11-12 AFR. No clue as to what caused the problem. Mod's to fuel system are just a walbro, 550's and afpr set to 35 psi. Let me know what you guys think.

 

[WhtMa71]

What problem?

 

[kotu100]

In other words you've given the car a lot more fuel but haven't done anything to adjust the air/fuel trim. So until you do it will run rich.

 

[chuckmuska2005]

The engine is running rich with adjustments made on the afc controler. that is the issue. should be running 14.5ish on wideband.

 

[Supracentral]

walbro, 550's and afpr set to 35 psi.

No Lexus AFM? You've added at least 25% to the fuel, possibly more. What's your airflow correction factor set to?

 

[chuckmuska2005]

correction goes from -12 to -30 from idle to 5500 rpms

 

[Supracentral]

There's your answer. You're running 25% more fuel and you've reduced your airflow signal by 12% at idle... It's going to run rich. Also, because you're starting out with a baseline so far from 0%, you've effectively halved the adjustment range the Neo is capable of. Put a Lexus AFM on it and reset everything to 0%, then start your tune.

 

[chuckmuska2005]

Way I figured it is if i decrease the airflow signal it wouldn't add so much fuel. So aside from the lexus air meter. If I increase the airflow signal it should run more stoich. I ran a neo on my 1j and had no issue like this before. Thank you supracentral for your help.

 

[Supracentral]

Way I figured it is if i decrease the airflow signal it wouldn't add so much fuel. So aside from the lexus air meter. If I increase the airflow signal it should run more stoich. I ran a neo on my 1j and had no issue like this before. Thank you supracentral for your help.

Different system. The 7M-GTE uses a Karmann-Vortex air flow meter - it's a cranky bitch to begin with. The Lexus AFM is almost exactly 25% larger than stock. 550cc injectors are also 25% larger than stock. They compensate for each other. Also, because you are reducing the air flow signal overall by 25%, fuel cut moves up, way up. Then as you tune, and take more fuel out to get it right, fuel cut goes even higher.

The whole Lexus/550's mod is very well though out. With the NEO you should be able to fine tune it to get the car running perfectly.

 

[chuckmuska2005]

ok, i found where I made my mistake. thought the signal type was a flap changed to karman now, got the lexus afm on the way. thanks for the awesome tech advice supracentral.