trying to fix the lean problem.

[boostaddict]

after putting on my upgraded ct26, lex, 550s, i had the problem of the car running lean when it hit boost. well i finally got a safc hooked up to it and added fuel throughout the rpms to compensate for the lean problem. now the wide band i got it to richen up at full boost but now its seems to me to be hitting fuel cut. when it reaches 17psi the car will shut down. i have a manual boost controller which is only open 2 turns. i was just wondering if anybody knows another possible problem or has ever been through this? thanks for any help in advanced. if you need to know anything else let me know.
tyler

 

[jdub]

Hitting boost cut at 17 psi on the Lex/550 combo is about right...I hit it at 18 psi. When winter comes around with lower OATs, you will hit boost cut at a lower psi.

 

[boostaddict]

my boost controller is turned almost all th way down though. so i guess my question if the boost controller is down shouldnt it be at stock boost? think id be better off trying to disconnect the boost controller and see what happens?

 

[grimreaper]

Adding fuel with the safc is going to lower fuel cut. Running lean on 550's with a ct26? something doesnt sound right, is your fuel pressure rising with boost?

 

[AndyMac]

If you upgraded the turbo and afm then your "stock" boost will be slightly higher than what the stock boost would be on a stock supra. You have opened up the breathing, allowing the car to get more air, which = more fuel, which equals more boost.

 

[boostaddict]

grim i thought the same thing. but in a previous post i was told to get an safc. so i did hooked it up and now i got it running rich with it. just now its hitting fuel cut so i tried turning the boost down and still does same thing

 

[jdub]

When you say "I got it running rich with it", exactly how rich at 3000 RPM to WOT.

What is cruise (off boost) AFR?

Have you tested the wastegate actuator for proper operation? And, confirmed it's not shimmed?

 

[boostaddict]

well i added 12% more fuel to it from about 2800 up and got it to hit 10 on the wideband as a starting point. i still have to screw around with it to get it where i want it but id rather be rich then lean. i have not tried testing the actuator yet i didnt even think of it will try that next time its not pouring out here.