I finally got my car together and got the wideband installed. Now I’m trying to get it tuned.
Here is my setup:
sr20ve
T28 (from a GTI-R)
Stock wastegate @ 7psi
Greddy Type S ripoff bov
STI yellow sidefeed injectors
sr20ve MAF (blow through)
Calum Realtime ECU (I can make changes to basically anything on the fly)
AEM UEGO wideband
I took it out for a couple pulls and it seems like it is running pig rich. If I do a pull in 1st or 2nd, it pulls pretty hard, but if I do a pull in third, it just stumbles all the way to 7500. I have a base tune for my setup loaded on the ECU, so it shouldn’t be off by THAT much. I did a boost leak test and the turbo, pipes, and the IC are all good up to 15 (as high as I went). Now, this is where it gets tricky. It seems like there is some pressure seeping into the crankcase. I have my valve cover vented to atmosphere and when I plug it for a couple seconds and release, there is a burst of air, then a steady flow again. I also have my PCV vented to atmosphere (the PCV is bad, so it is bypassed) and the hose that went from the PCV to the intake manifold is capped off.
So, is it normal to have the pressure seeping into the crankcase? Would that be effecting these rich conditions? Any ideas? Is anyone around the Plum/Monroeville/Pittsburgh area familiar with tuning nissans?
I have tried adjusting the kvalue for the injectors to lean it out a bit. It definitely helped a bit, but it is definitely not the fix in this case. Default kvalue for this bin is 196. I had it all the way down to 165 and it was still pegging ~10 on the wideband.
Here’s a quick pic. The red circles are where the air is coming from. (The one on the TB does not leak until 15-16psi)
Hm, I’ll double check the MAF this weekend. The MAF is 16 inches from the Throttle body with a single pipe with a clamp on each end. I coudln’t hear any air coming from anywhere other that the Valve cover (except the throttle body as mentioned above, which only happens at 15+psi and is verrry slight)
Try closing the gap down to .028 and see if it makes any difference. Since you’re running blow through try rotating the maf in a few different positions. Sometimes they can be sensitive to positioning.
Ok, I’ll give that a try. I’ll have to pick up another gap tool. I left mine sitting in the engine bay when I gapped them last. As I was driving I heard “clank, ping ping ping” LOL. As far as the MAF, I’ll try twisting it a little. It is maybe 10* from top dead center.
The number on the MAF says AFH70-16A and it is a Hitachi. Is this a VE MAF or not? because I thought VE MAFs were good up to ~300hp. Mine is hitting ~5.05-5.09v in the higher RPMS (7000+). I have my ECU setup for the VE MAF, so if this isn’t it, this could be my issue.
Ok, I gapped them to .028 and twisted the MAF to straighten in out. It seems to be running a little bit better now, but still not great.
i would just get yourself a maxima maf or a z32 maf and set the computer up for whichever one you choose. they are way easier to get and diagnose any problems.
The VE maf is the same as one of the later model pathfinders, I can’t remember the exact year though. I know Jason already touched on this but If you ever plan on using an N62 maf in the future then you might as well try an N60 out now (for the sake of troubleshooting) since they are good for 325hp and use the same pigtail.
I’m runnning stock 3 bar pressure. I have the stock pump and fpr on there.
I think I might just shop for an N60 or N62 now and find a nice one. The 92 Maxima has been sitting for a while so the MAF might not be good. I’d rather not swap an incorrect MAF out with a non-working MAF :doh:
