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Discussion Starter · #1 ·
Do you guys know if my supra is suppose to shake/rumble... at idle. Like if I am at a redlight with my foot on the brake and gear in neutral. The rpms stay around 650. It feels like the car is about to die.
Is that normal or some thing is wrong? I started noticing this after I had my stereo off, which I rarely do.

THank you
 

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Discussion Starter · #3 ·
Do you think it is my safcii?

Some one please help; Now I am scared to drive my supra.

If the safcii might have caused it, can some one give me a basic setup I should have on my safc with the following mods:
cam gears
k&n intake filter cone
(i'll be getting an exhaust soon)

THank YOu
 

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10'S BABY
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iirevolverii said:
Do you think it is my safcii?

Some one please help; Now I am scared to drive my supra.

If the safcii might have caused it, can some one give me a basic setup I should have on my safc with the following mods:
cam gears
k&n intake filter cone
(i'll be getting an exhaust soon)

THank YOu
I am not a NA guy, but with those mods and assuming that you never tuned with that SAFC II you should not have to worry about any lean issues. The stock ECU richens the mixture up plenty with the upgrades you have mentioned. Personally I would adjust the idle a bit and dont be too concerned about it. If you really want to make sure, hook it up to an A/F gauge and see for yourself.

Maybe a NA guy will chime in with a more specific answer
 

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Could also be Throttle Position Sensor , have you gotten any check engine lights?
 

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Discussion Starter · #8 · (Edited)
SAFC-II Setting:

>Settings
1. Hi-Thrtl
Fi1
1000
+/- 0%
(Hi)

2. Lo-Thrtl
Fi1
1000
+/- 0%
(Lo)

3. TH-Point
Lo Hi
10% 50%

4. Ne-Point
Ne01: 1000 rpm
Ne02: 1600 rpm
Ne03: 2200 rpm
...so on in 600 rpm incriments....
Ne12: 7600 rpm

5. Dec. -Air
Thr ****%
Ne1 10.0%
Ne2 10.0%

6. KnK Set
0 0 rpm
1: 0 1500 rpm
2: 0 3500 rpm

7. DataFile
File1: ON
File2: OFF

I have never used an afc before and I dont know how to change setting unless if some one gives me specific instructions. The afc came with the car when I bought it, and the previous owner also removed his blitz catback exhaust and put on the stock exhaust before he sold me his car.


Geddy Lee said:
Could also be Throttle Position Sensor , have you gotten any check engine lights?
No. I dont have any check engine lights.


SupraDupra_17 said:
Have you been able to read all of your AFC readings yet? For the entire RPM range?
Again, I dont know how to use the safc, what should I do to read all my afc readings? or do you mean like thr,rpm,knock,air,...etc. How would I get the readings throughout the rpm range.


Is it safe to drive my supra like this?
 

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Discussion Starter · #9 ·
Any help guys.

Can I still continue driving like this, or will the low rpm at idle cause other problems?

THANK YOU
 

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Ok, like I said before. You would have to select settings, then select lo-thrtl, then you will see 1000 rpm at 0%. Now, if you use the pivot button to move to the right, the rpms will increase all the way to 7800. You would be inccreasing by 200 rpm and would be able to read the % for each rpm. You would do the same with the hi-thrtl.

Let me know.
 

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Discussion Starter · #11 ·
Ok. I just started the car in the garage since last nights drive and the rpms are around 1300. So I figured that the rpms drop to around 650 after I start driving my car for a while.

I did what you told me and yes it is 0% at 1000 rpm but it is increasing by 600 rpm and goes all the way to 7000 rpm and it is 0% all the way to 7000 rpm.

Do you think I should increase the 0% to like 3 or 5 % at 1000 rpm, to help keep the car from shaking?

Thank you
 

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So, your AFC hasn't been tuned. You really shouldn't mess with it until you properly read your A/F ratio. Then you can tune it yourself. I tuned mine while I was dynoing my car.

And when you checked it, was it for Lo-Thrtl or Hi-Thrtl, or both?

You can adjust your idle with the AFC or underneath the hood.
 

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Discussion Starter · #13 ·
SupraDupra_17 said:
So, your AFC hasn't been tuned. You really shouldn't mess with it until you properly read your A/F ratio. Then you can tune it yourself. I tuned mine while I was dynoing my car.

And when you checked it, was it for Lo-Thrtl or Hi-Thrtl, or both?

You can adjust your idle with the AFC or underneath the hood.
Yes, I checked both Lo-Thrtl and Hi-Thrtl and it was the same for both meaning, according to you, not tuned.
I will be getting a NA Turbo kit this summer and I will be also buying a wideband a/f gauge and setup. So I or a professional will tune it later.
Or would you think that it should be tuned now?

How can I adjust the idle with the safc?
and if incase, how can I adjust idle underneath the hood?

Sorry that I am being a noob, I am not mechanically inclined, but I am trying very hard to learn about these mkivs'.

THANK YOU
 

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It doesn't matter if you tune it now or wait until you're turbo.

Now that I think of it, I'm not entirely sure you can adjust the idle with the AFC. To adjust it underneath the hood, you find the throttle cable and adjust the screw. Your idle should be around 750.
 

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Discussion Starter · #16 · (Edited)
98mkiv said:
does it hold a steady idle?
No, not steady. Ranges from 650 to about 800 rpm. But mostly stays around 700 rpm.

SupraDupra_17 said:
It doesn't matter if you tune it now or wait until you're turbo.

Now that I think of it, I'm not entirely sure you can adjust the idle with the AFC. To adjust it underneath the hood, you find the throttle cable and adjust the screw. Your idle should be around 750.
I know the red box is the thrtl cable, right? Are you talking about the screws/nuts around the middle bracket?
Where is the setting written like the 750 you mentioned?

 

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Discussion Starter · #18 ·
So wait, how am I suppose to adjust it?
Do I losen or tighten the nut/screw?

Once again, tonight the cars idle went low as 600 rpm and sometimes slightly below 600 rpm.


THANK YOU VERY MUCH FOR HELPING ME.
 

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Discussion Starter · #20 ·
SupraDupra_17 said:
You would have to loosen it then pull the cable tighter and then retighten the nut.
How much should I pull it?
Is it easy to pull the cable back, or will I have to tug it hard?

THANK YOU
 
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