Idle Issue with Q45 Throttle Body

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mdlesk
 

Posts: 17
Joined: Fri Aug 05, 2011 1:47 am

Idle Issue with Q45 Throttle Body

Post by mdlesk »

I just got done with my build and I am just now starting the tuning process using NISTUNE. I cannot get the car to idle. I have the XCESSIVE KA24DE manifold with the Q45 throttle body. I tried adjusting the screw and that does allow me to start the car without having to push on the pedal, but it doesn't stabalize it, and then after about a second it will drop it and then stall. I am using the Q45 TPS with the bottom harness hooked up. The top harness isn't hooked up at all. Is there something that I am missing? The throttle body doesn't have any vaccum lines or coolant lines running through it. I have those capped off. I have also removed all emission related items.

What I have done so far is:

Install all parts
Install NISTUNE Rom Pack
Install NISTUNE (v. 10.12)
Connect to Consult
Sync image from ECU to NISTUNE
Operations -> Change injector size for 1000cc (I have the ID1000's).

Parts currently installed:
XCESSIVE Manufactoring Intake Manifold
Q45 Throttle Body w./ OEM TPS
Injector Dynamics ID1000 Injectors
OEM S14 KA24DE MAF
Braided Fuel Lines
Aeromotive FPR
AEM Fuel Rail
JGS Brake Booster Vaccum Block
ISIS KA24DE Exhaust Manifold
ISIS RS3871 Turbo
ISIS 02 Screamer Dump Pipe
ISIS M-SPEC FMIC
ISIS SR20 Intake Kit (Shortened tubing to fit S14)
Megan Racing KA24DE Downpipe
APEX-i Test Pipe
APEX-i R95 Cat-Back Exhaust

I appreciate any help on this.

Thanks,

Michael
modulation
 

Posts: 149
Joined: Tue Jan 15, 2008 1:51 pm

Re: Idle Issue with Q45 Throttle Body

Post by modulation »

There are a few maps that deal with the idle target rpm. (I'll look them up when I get home.)
Make all of those maps target a low rpm (like 200-500rpms) and make sure you set your idle above that.

Right now it could be 1 of 2 things.
1. At idle q45 throttle body is just so large for small amount of air car is pulling in, that the air flow is too turbulent cause the changes in idle.
or
2. Your car is trying to adjust the iacv and timing to move the idle higher/lower.

If you change our idle target maps then at least that will rule out #2.

I have a ka24de with no iavc and I set idle by throttle body screw. Idle is pretty stable but I had to tune the maps I'm talking about.
Matt
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Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
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Re: Idle Issue with Q45 Throttle Body

Post by Matt »

Since its really only the injector sizes that have changed inside Nistune the only thing with idle I can think of tuning wise is the latency hasnt been adjusted?

What is that currently set to? What are your AFRs at idle like?
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