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Why does my car untune itself after a couple days?

Old 11-02-2004, 05:45 PM
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Default Why does my car untune itself after a couple days?

Why does my car untune itself after a couple days?

It idles fine after loading the tune...but gets progressively worse (hunting up and down from 600 to 1300 rpm).

What can I do to make the tune stick?
Old 11-02-2004, 05:57 PM
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hey there, send me your file ill take a look at it and see if i can change the idle block relearn proceedure.. jessebubb@yahoo.com
Old 11-02-2004, 05:57 PM
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Originally Posted by soslo
Why does my car untune itself after a couple days?

It idles fine after loading the tune...but gets progressively worse (hunting up and down from 600 to 1300 rpm).

What can I do to make the tune stick?
Hmmm. Let me guess. Cammed car, with a MAF and a lid right? Because your fuel trims that are learned from your MAF readings being wrong are driving your VE fueling so far pig rich that your car doesn't want to run.
Old 11-03-2004, 03:49 PM
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Wait4me,
How do you change the idle relearn? Oh, you do custom programs?
Old 11-03-2004, 06:17 PM
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Originally Posted by Another_User
Hmmm. Let me guess. Cammed car, with a MAF and a lid right? Because your fuel trims that are learned from your MAF readings being wrong are driving your VE fueling so far pig rich that your car doesn't want to run.
Good guess, but slightly off. Stock MAF.

Mods include heads/tsp 225 cam on 112LSA, M6, pulley, lid, etc.
---Stock exhaust system---

I have multiplied the VE table in the first 3 cols by 60, 80, and 90 roughly, among other tuning. It idles beautifully for about 2-3 days, then goes back to hunting.
Old 11-03-2004, 06:42 PM
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Originally Posted by soslo
Good guess, but slightly off. Stock MAF.

Mods include heads/tsp 225 cam on 112LSA, M6, pulley, lid, etc.
---Stock exhaust system---

I have multiplied the VE table in the first 3 cols by 60, 80, and 90 roughly, among other tuning. It idles beautifully for about 2-3 days, then goes back to hunting.
No no...I meant "with a MAF". Cause I don't use one. You need to unplug the MAF, tune your VE, then put your trims close to 0 with the MAF plugged in by multiplying the entire MAF table. That will put you in the ballpark.
Old 11-03-2004, 07:40 PM
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So...is the maf unplugged while I drive the car around?
Old 11-03-2004, 08:30 PM
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Originally Posted by soslo
So...is the maf unplugged while I drive the car around?
Yes. Refer to the speed density tuning instructions on here and the HP Tuners website. You will need to tune your VE table based on fuel trims. Definitely start with a scaled table. You will probably still end up dropping it 15-25% at some points.
Old 11-03-2004, 08:33 PM
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Just make sure your IAT sensor is still plugged in and tune away. You might never plug the MAF back in...
Old 11-03-2004, 10:52 PM
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Originally Posted by Another_User
Hmmm. Let me guess. Cammed car, with a MAF and a lid right? Because your fuel trims that are learned from your MAF readings being wrong are driving your VE fueling so far pig rich that your car doesn't want to run.
Damn. That is what been happening to mine. My is running real rich at idle, where before it didn't.
Old 11-03-2004, 11:02 PM
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Originally Posted by wait4me
hey there, send me your file ill take a look at it and see if i can change the idle block relearn proceedure.. jessebubb@yahoo.com
Jesse,
I have noticed on several forums that most of the time you don't help people out with their questions, but instead just fix there files. That is great and all, but for us that want to learn, it sucks. JMO.
Old 11-03-2004, 11:08 PM
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I sent him my file - and am going to compare the changes he makes with my tune and try to learn from that...


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