Thread: Well how about that? Running lean

If you guys remember this thread

http://www.sr20-forum.com/vvl/45446-went-strip-not-so-well.html

Months ago I did the swap and never realize how my car was running, today I installed the wideband and notice the flawless idle and 14.7-15.2 AFR, that's ok so I took a spin and went WOT

3500RPM --- AFR (literally, no reading )
4000RPM 13ish AFR
4500RPM 14ish AFR
5000RPM 16ish AFR
5500RPM 16.5 AFR
6000RPM 17.0 AFR
6500RPM released the pedal, I was frightened
*Neither AFR or RPM are exact just giving the idea

So that's the reason of my car being slow, I'm glad I've been nanny driving and promised myself to be easy until getting it tuned.

I don't think is the gas map since looks correct and the idle AFR's tell me the K is right

The injectors were taken to a shop to get em cleaned just before dropping the VE in so I don't think they're clogged

If the FPR were broke would mess with the idle and partial throttle AFR's right? because both are right in place

I'd say the fuel pump is not supplying enough fuel, in this forum I read the case of somebody who posted that his car never ran well until he changed the fuel pump.

What do you guys think?

What air/fuel gauge? Did you configurate it? Were is it located?

BTW fuel filter is a Z32TT OEM Nissan with a few hundreds on it and the previous fuel filter was clean as hell

AEM UEGO Wideband

The bung is bolted just where the shifter assembly is

Was it brand new prior to install? Before you install your supposed to turn the key on(not start it) wait like 5seconds then install in the exhaust/header.

Geeez scary. Your pump might be failing you unless your getting some kind of restriction

Brand new Wideband and even when I didn't know I turned the key prior to starting and wait about a minute.

So glad I haven't go back to the track, what kind of restriction should I look for Cory?

Should I lose the FPR vacuum hose and give it a try?

what do you tune with? basic? realtime?

Do you have a fpr gauge. You can bolt one up route it so it lays on top of the cowl and go for a spin. Btw for some reason alot of the bins that work well for others like calum and various jwt tunes start out fine but end up real lean up top. I tried about three different bins and they run lean, and it is just just my car either. Check your pump though, if anything add a relay that should help the pump a bit.

When I read your description, I suspected the fuel pump. You can replace it with a Walbro for under $100. This might be worth doing just to remove the fuel pump as a possibility. Then you can focus on other possible causes.