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Well, I'm almost done with the VE swap in my B15. Injector subharness is done, and I am a few vacuum lines and connections away from attempting to start the engine with the B15 ECU (for now; I will be converting the harness to use a B14 ECU after).
However, I am stumped on something.
Regarding the SR20VE IACV-AAC wiring... When I look into the B15 FSM (and the IACV connector), I see there are 6 wires connecting to the unit. However, the SR20VE has 4 (on 2 plugs), so I know that some rewiring will be required. Since people have been running B15's with B14 ECU's I'm guessing that it is possible to do the opposite (control the IACV-AAC with the B15 ECU).
Where it starts to be odd is when I check out the ECU connections. The B15 unit uses pins 6, 7, 15, and 16 (the 2 remaining ones on the connector are power leads).
Now, when I go to the JGY customs page for B15 to B14 ECU conversion, I see that the IACV-AAC open valve is "101 to 6", so we are still good. However, what happens with the rest of them? Are they still necessary? Where does this lead go to on the SR20VE unit? What about the 3 other wires on the VE?
What would really help me out is a pinout diagram with descriptions of the SR20VE IACV-AAC connectors. Would anyone happen to have them?
Searching around helped me understand how this works a bit more, but I have no solution yet.
EDIT: Searching around a bit more yielded this (color is VE harness):
BR goes to O2 sensor feed
This would be a guess, but would the SB go to pin 6?
That would take care of the brown connector. What about the purple one? I've read somewhere about the AC.
__________________
Matt
2001 Sentra SE/pp (SR20VE powered)
well what i did was put sb to pin 6 and then i had the other one go to one of the two power leads ...
the purple connector i didnt hook up yet but it goes to the a/c and something else to stablize the idle when the a/c is on...
however my cel light is still on for idle and it is still jumpy at times and sometimes it wont go below 1200, but id say about 80% of the time it stays at 850-900rpm
Another note, when the evap canister is connected to vacuum the idle goes higher.. i think the reason is that on the rr manifod there is a sensor that controls the pressure for it...
__________________ KL0 P11 Sport
VE, JWT Pop Charger, Carbing: Tri-FSTB RSTB LCA Bar, SS Autochrome Header, Greddy Evo, Rear sway bar
------------ Surround Sound My VE thread
check for thread started by me in this forum and you will see i asked a simialr question... strakinsky (spelled wrong no doubt) posted a diagram showing where the purple plug will connect to.. i believe one goes to the o2 sensor and the other somewhere with a/c
Thanks for the info. As I was saying earlier, this is just for an interim setup, as I have a G20 ECU waiting to be installed right after, so when the ECU swap will be done, it will not try to send other signals to the IACV and rough out the idle (I guess that is why you are getting an unstable idle for 20% of the time).
I might wait on the FICD if I can't find the info before next weekend. I haven't refilled the AC yet anyway.
i have a b14 ecu in my car so its not the stock g20 ecu causiing the issue.. let me know when your done what you did.. also what did you do with the extra hoses for the power steering? and did you connect the evap hose?
Yes, evap hose is connected. I will install the PS hoses pretty soon using T connectors too. Also note that I do not have any problems as of yet (I haven't even had the engine run yet), but I do know for a fact that the idle is going to be rough if the AAC isn't connected, which is why I was asking questions.
Well, here is what happened for me yesterday:
1) I wired the AAC valve as shown above
2) I tried to start the engine for the first time. It did not start.
3) I plugged in the EGR temp sensor. The car started, but was in limp mode and could not idle properly. I also noticed I had a leak around my Nissport oil pressure adaptor. Spent half the day on taking it off, putting liquid gasket on it and putting it back on.
4) I plugged in the top part of the EGR solenoid and cleared all of the codes. The car started right up, and after seeing tach go up and down a few times, it went back to idling perfectly at around 750-800 RPM.
However, I am getting a P0505 code now, which is not a big deal if everything went well, but the car sputters at about 1750 RPM when coming off the idle. It sort of feels like there is a "one time" fuel cut, and once it goes back to over 2000 RPM, everything runs just fine. It will not do that when, for example, slowing down to about 1000 RPM and getting back on the throttle or when hitting the throttle hard from idle to make it go above 2000 RPM. I can still move around by launching the car at 2000 RPM, but it's not the best thing driveability-wise.
With all the time spent on the oil pressure adaptor, I did not have the time to redo the harness to use the P10 ECU, so I am still running the B15 ECU, and the PS hoses are not yet connected.
With all of the additional wires running to the B15 IACV, is the ECU expecting to get a reading it's not getting? What else could cause this? With all codes cleared, the P0505 code shows up exactly when I hit that "cut" for the first time.
From searching around on here, I think I may have found my problem. My TPS is misadjusted (I thought it had to be at 0V at closed position). I will readjust it tonight.
I just adjusted the TPS, and the "hit" at 1750 RPM has disappeared.
However, the idle is now totally wrong about 60% of the time.
I am still getting a bit of sputter when driving the car at constant speed, but I haven't driven it at very high speeds, since I was tesing it on residential streets. It may either be a problem with the spark plug gapping (I have BKR6E-N-11 which I haven't regapped, so the gap is probably a bit off), timing (we were unsure when we set it) or simply the crazy idle coming in play when I let off the gas too much.
For the idle, I'm pretty sure the ECU will fix it, so I'll probably drive around like this until I get the ECU back from JWT. I'll work on the plugs & timing (along with the two PS hoses), and that'll be it until I do the harness conversion.
The stock VE injectors, and I'm correcting with an AFC Neo, but corrections are somewhat on the rich side to be safe, so that may be my issue too. I'm waiting on the JWT ECU to go to the dyno.
Well, I have regapped the plugs last night, and the idle seems to be a bit more stable. While driving to the train station this morning, I got 0 hesitation, and a decent idle.
I still have to connect the A/C idle valve (the purple plug) and the 2 PS hoses. A/C valve is not a huge issue right now, as my A/C system is empty. From looking at the RR motor, it would seem that one of the PS hoses goes to the intake, and another goes to the plenum. I will try to find some time to go get the parts to make that possible.
civicdragon: For the AAC valve, did you wire it exactly as explained at the start of this thread? I'm just wondering if I should try changing the power feed for the O2 sensor signal.
Connected in this manner, the AAC valve seems to click about a dozen times when I put the igniton at the ON position, so I'm guessing this is where the idle goes out of whack. Is the AAC valve supposed to be very noisy, or just a single click?
Well if your running the b15 ecu of course your gonna have a p0505 code because the idle control circuit is not complete.
Now if you throw in the g20 ecu, you wont have that problem because the g20 ecu only monitors the IACV-AAC Valve ("brown" solenoid) while the IACV-FICD Valve ("purple" solenoid) is controlled by the A/C relay.
So if you want the FICD to operate properly you can ground one wire to the intake manifold (i forget which one exactly) and run the other wire to the wire that kicks the a/c compressor on.
So if you want the FICD to operate properly you can ground one wire to the intake manifold (i forget which one exactly) and run the other wire to the wire that kicks the a/c compressor on.
see if you can find out cause i need mine to be hooked up too
Last edited by civicdragon : 07-05-2007 at 02:25 AM.
