Care surging at 1800 - 2400rpm and Lean Codes

[Motleydrew]

It seems to buck at bit. My check engine light is also coming on displaying a lean condition (code 41, 91). I have a 8:1 FMU with 24lb injectors and 255lph
pump. I ordered a 10:1 FMU recal kit. I cannot tell if this is do to full throttle or just around town type driving because the light comes on at different times. Any ideas? My timing is also at 10. Dumb question but does the Mass air meter inlet tube face the same direction as it did before the SC install?
Can a bad ground cause this? I do have a relocated battery.

please let me know if you have any ideas on the cause of these issues :)

thanks


car has GT40 crate Motor
aluminum X Heads
E Cam
SC Trim seems to make 6.5 boost

[Tom Keiser]

Moteydrew,
I installed an SC trim in March and had a terrible time figuring out why it bucked and surged. After adding a bypass valve and taking the tubing apart countless times, I finally figured out that I had installed the Mass Air meter backwards . Turned it around and it works great. The big end of the sampling tube goes toward the filter. Cancel the 10:1 kit if You can, 8:1 is correct for 24lb. injectors. Timing at 10 (spout out) is correct, I ended up with .030 plug gap after trying several different gaps. Good Luck!
Tom

[Motleydrew]

Thanks For the info !!!

Mass air is fine
gap is at 36 right now


I may have found part of my problem. Its kinda a funny one like your mass air meter one. I was looking behind the intake and noticed the ground for the fuel injection system was just sitting on the Tranny bellhousing....oops :)

So I reconnected, have no codes yet, I'll keep my fingers crossed.

Thanks again Bud

[Tom Keiser]

That's good news. Grounds can do wierd things when they are not hooked up. I hope that was Your cure.
Tom