SR RUNNING LEAN im stumped

[240-slide-ride]

ive got a 89 s13 with a s15 sr swap, and it is running LEAN. the timing is correct crank pulley, cams etc, ive counted the teeth going from cam dimples to head and it's all dead on balls. the car runs good and starts ok, goes into boost very strong but falls on its face at a certain point. after that happened i pulled the plugs and they were white, even the electrodes were white. i havent got a vacuum gauge or a timing light on it yet but im working on that. also the CAS is cranked almost all to one way to get it to run/start. what else could be causing my car to run so lean? i havent been driving it since finding it lean. another thing i have noticed is it came with a electronin boost controller that appers to be not hooked up, and it looks like the lines under the hood were removed but not hooked up as well, could this have anything to do with this? btw there new spark plugs gapped at 27 i had them at 32 before, seems to have done nothing

[dwaynedman]

Where are you running lean at ?? Do you have a wideband ?? Is it only at a certain RPM or under hard load? I am having almost the same problem, and cannot come to a conclusion for it. My car KA24DE S-14 96 OBD2 Runs and idles great, approx 14.8-15.2 AFR @ idleCruising speed under soft pedal pressure 14.7-14.2 AFR@ WOT on hills or straight, it dips to 12.5-13.0 AFR for a couple seconds then goes off the chart lean past 17 and cuts a little "hesitates" Cannot put my finger on where it is coming from. I was running a full KA-T setup, and have put it back to stock. With stock ECU and all, and still am running lean.

Currently on car is :

Walbro 255Adjustable FPR264 Crower Cams3" full esxhaust

Sorry not trying to hijack your post, just thought there might be a similarity that can help us both out.

Thanks,D

[dwaynedman]

So I seem to have partially fixed my problem. I tested the ground to MAF and found I had 48 ohms resistance. Wired ground straight to engine block, and most of my lean condition went away. It now dips at WOT to 13.5 then 12.5 then 11.2 under hard load, but around 5k RPM it still shoots over to full lean until I let off the gas and stomp it again. After a couple seconds of load, it shoots to lean again, and I can take my foot off the gas and get on it again goes back to 12.5. So basically it is still lean under hard load, just not as bad as before. WTF is going on ???

"@ 240-slide" You may want to check your engine grounding and MAF sensor ground wire. That has helped me so far, and I am starting to look into the rest of my grounding system as I am suspecting bad wires. I will keep you posted, and let you know if I found a complete fix.

ThanksD