550cc + Lex AFM running lean (Cressida)

Donedreamin

Member
Oct 6, 2009
48
0
6
Toronto
Hey guys,

I'm a little stumped confused, either way mod details -

550cc
Lexus AFM
Aeromotive AFPR
Walboro
57 trim

Anyways i'm doing some test runs and i'm leaning out, i bumped my AFPR up and it corrected it a bit but i've got good numbers up till 3-4k than it starts to lean out and bog (i have a wideband)

How is this even possible?
Is there something i could have hooked up incorrectly?
How should i narrow down the culprit?
 

Another MkIII

Member
Feb 22, 2009
697
0
16
Chicago
What fuel pressure are you running, any codes, what are your AFRs, and what is your VF reading? Also, what wideband do you have and how old is it?
-AM3
 

Donedreamin

Member
Oct 6, 2009
48
0
6
Toronto
AEM wideband

I was originally running 30psi at idle, but bumped it to 40, than 50 and it made a small difference..

And, i just stumbled across this " With the LEXUS AFM installed, start the engine when COLD with NO THROTTLE opening at all - see if it idles, or if it stalls. IF it refuses to idle, or idles very roughly-threatening to stall, then your fuel-system is running too lean with the 550's installed, and you need to find out why: (Injectors not at spec / Low fuel-pressure / other). "

And my car will stall if i don't give it gas..
 

Donedreamin

Member
Oct 6, 2009
48
0
6
Toronto
So..

I found my problem, seems as though i have wired my fuel pump incorrectly; it literally melted a 30amp fuse.. i dont quite understand where i went wrong but have a good idea, and this is a cressida btw. any help is much appreciated

IMG_1348.jpg
IMG_1349.jpg
IMG_1351.jpg
 

Nick M

Black Rifles Matter
Sep 9, 2005
8,897
40
48
U.S.
www.ebay.com
You don't need to trim the signal with an sort of SAFC, regardless of brand name. The screw on the Lex meter will do it, all the way out to 11.5:1, or very rich like stock if you take it in.
 

roadboy

Supra Owner
Jan 22, 2008
456
0
16
34
Toronto, Ontario
mine ran lean with walbro, 550 and lex afm (stock screw adjustment)
drilled the cap and twisted the screw in. and it ran better
iv seen people who dont adjust it and they are fine, and seen people who had to adjust it to run properly