1JZ runs better with an air leak?

[BlackMKIII]

So last Saturday, I installed my Aeromotive AFPR kit. While I'm doing it, I notice a vacuum line to the power steering unit had popped off. (This line goes from the top of the p/s pump to the manifold, just behind the throttle body) Guess I was boosting better than I thought. :biglaugh:

Anyway, I get the AFPR kit all hooked up, fire it up and it runs great. Then I remembered that vacuum line. I put it on the pump, and the idle drops to 350, it's running rough, then it dies. I take the line off, and it's perfect. It doesn't make sense to me, maybe it will to someone here.

I need to get this sorted out today, because I need to get it tuned later this week. :1zhelp:

TPS Voltage is around 0.504V closed, max is 3.825V. Maybe there's a problem with the MAP sensor?

 

[BlackMKIII]

Okay, so I got it to sputter out with the line on. ECU flashes code 31 and code 34.

31 - Air Flow Meter. Say what!?!? That doesn't even begin to make sense! What the hell is an AFM code doing in my 1JZ???? Well, maybe it's actually a MAP code.

34 - Turbocharger Pressure is abnormal. Okay, another pressure code. But this is the code that comes on when I hit Fuel Cut.

Does anyone out there have any idea what the hell is going on?

 

[BlackMKIII]

OMGWTFITFIXEDITSELF!!!!

No seriously. I cleared the EFI codes by pulling the EFI fuse, started it back up and just let the fucker idle on its own. Then, about 20 minutes in, the idle kicked up to 700 RPM like it was perfectly fine. Needless to say, I was STUNNED. I revved it up, it came back to 700. Revved it WAY the fuck up, right back to 700.

Amazing.

 

[AF1JZ]

Congrats then!!!

 

[nyteryda]

doesn't the 7m and 1jzgte electronically set the idle itself?

 

[soapra]

What is the fuel preassure at when you don't run Vaccum to the AFPR? When you reset the ECU (unplug the battery) the ECU needs to learn the fuel mixture and it looks at the O2 Sensor to find the right iddle. Also the iddle speed control valve gets sticky over time. You may want to clean it out. Look in to all of this if that Iddle thing comes back.

 

[BlackMKIII]

Static fuel pressure is set @ 38 PSI until I get on a dyno and crank it up to 45 when I tune the AFC. I was thinking it might be the ISC valve, but then everything just clicked and ran perfect. It was like someone flipped a switch. :dunno:

 

[pogoism9]

What is the fuel preassure at when you don't run Vaccum to the AFPR? When you reset the ECU (unplug the battery) the ECU needs to learn the fuel mixture and it looks at the O2 Sensor to find the right iddle. Also the iddle speed control valve gets sticky over time. You may want to clean it out. Look in to all of this if that Iddle thing comes back.

Exactly. The ECU isnt going to run the car very well upon first power. You need to run the car for 30-50 miles before it really gets running good.

 

[BlackMKIII]

Yeah, just drove it for about 10 minutes in the city. No problem found.

 

[s14eva1]

make sure next time you set the fuel pressure with that PS vac line hooked up....and only disconnect the vac line on the FPR to set the pressure correctly.