Tune gone after amp install?

Cleanoh4

Cleanoh4

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Aug 27, 2013
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I already pm'd Jenna and asked her, but figured I'd ask here too.

I had an amp/sub installed today and for w/e reason it feels like my tune is gone.
Is this possible?

Would having the battery disconnected for an amount of time needed to install cause it to "reset" the ecu effectively deleting the tune?

Could it be a grounding issue? If so wouldn't there be other problems?

Or is it in my head?
 
Gannon said:
I thought about that. But I don't see where it would effect power, only electrical, lights, system, etc. I wouldn't think hp would come from the alt.
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Kinda what I thought too,but that's what she suggested. My hids aren't dimming or anything. It just feels less snappy and like its slow to shift
 
Maybe the computer just needs to "relearn" it's settings after being disconnected and it'll take a few cycles?
Idk, I'm just mildly disappointed/concerned. It's every reason why I hate not doing my own work
 
Cleanoh4 said:
Maybe the computer just needs to "relearn" it's settings after being disconnected and it'll take a few cycles?
Idk, I'm just mildly disappointed/concerned. It's every reason why I hate not doing my own work
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That's how you learn though. Yea, try a relearn. Just can't wrap my mind around how a alt would reduce hp. That would mean the alt is spinning slower, which would mean your motor is spinning slower, reducing power.but the motor is going to spin on average 600-800rpms.
 
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Gannon said:
That's how you learn though. Yea, try a relearn. Just can't wrap my mind around how a alt would reduce hp. That would mean the alt is spinning slower, reducing power.but the motor is going to spin on average 600-800rpms.
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Typically I do all of my own work, truck has never been in the shop for anything at all except body work. I only had this done because the price was good and I wasn't going to have the time for a while.

Never done the relearn, link would be great.

And I can't either it really just doesn't make sense. And that fact that there really isn't a "problem" just that it feels different is what bugs me more.

Even at idle and going off the dummy gauge, and with the most bass heavy music I could find it only dipped about a volt,to like 12.7-13.5 maybe. I know the battery is older but the alt was just replaced this past winter.....
 
if the alternator is under powered it would be trying to charge harder meaning more resistance on the serpentine system and would also be putting less voltage to the ECM, injectors etc.. makes sense to me just unlikely that it would cause that much of an issue
 
Tylers88 said:
if the alternator is under powered it would be trying to charge harder meaning more resistance on the serpentine system and would also be putting less voltage to the ECM, injectors etc.. makes sense to me just unlikely that it would cause that much of an issue
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Like I said its not really an "issue" it just isn't as responsive as it had been before. I do however follow your logic. It just feels detuned, and back to stock shifting
 
Electricity is the heart and soul of an LS engine, Controls timing, Spark, and tells you engine/trans what do do/how to adjust. Lack of Electrical power could greatly effect performance.... :imo:
 
Gannon said:
Go to nelsonperformance.com and look at faqs. It will show you how to do a relearn.
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They only have the security relearn, the truck starts and drives so I don't need that. I thought there was a PCM relearn...
 
ECM reset is as follows:

Key in on position
pull ecm1 and ecmb fuses
wait aprox 5 minutes with key on
key in off position
replace fuses
start vehicle...it may run rough a bit at first for a few seconds.

Found this on pt.net, any harm in giving it a shot?
 
AlwaysSomethin said:
Electricity is the heart and soul of an LS engine, Controls timing, Spark, and tells you engine/trans what do do/how to adjust. Lack of Electrical power could greatly effect performance.... :imo:
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Ok so, million dollar question; any harm in running it until I get a 200amp alt? If in fact that's the real issue
 
Cleanoh4 said:
Ok so, million dollar question; any harm in running it until I get a 200amp alt? If in fact that's the real issue
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It's worth noting this isn't a monster system, it's a single 10" and a 250max watt amp

Any suggestions on alternator upgrade amp range?

Also would disconnecting the power from the amp to test if it is the cause work?
 
Cleanoh4 said:
It's worth noting this isn't a monster system, it's a single 10" and a 250max watt amp

Any suggestions on alternator upgrade amp range?

Also would disconnecting the power from the amp to test if it is the cause work?
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I wouldn't think it would have caused as big of an issue as you're having but as stated stranger shit has happened, pull the fuse see how it acts more likely than not it needs time to relearn like you thought before. As for the bigger alt I don't have a clue, in my OBS I just got the biggest factory(105 amp BOO) lifetime warranty one and dealt with changing them every 11-12 months lol but that was a decent sized stereo
 
There's a company on ebay that sells 200 amp alts for our trucks. I bought one for my old tahoe. It is very slightly oversized but fits perfectly fine in the stock location and I never had a problem with mine. I bought it because I had an underdrive crank pulley. The alt also came with a smaller than factory pulley so it's spins a little quicker. I'd recommend it. The store name on ebay started with a B but I don't remember the exact name

Sent from my One X using Tapatalk 4
 
Tylers88 said:
I wouldn't think it would have caused as big of an issue as you're having but as stated stranger shit has happened, pull the fuse see how it acts more likely than not it needs time to relearn like you thought before. As for the bigger alt I don't have a clue, in my OBS I just got the biggest factory(105 amp BOO) lifetime warranty one and dealt with changing them every 11-12 months lol but that was a decent sized stereo
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Yeah I'll pull the fuse and see if that helps, if so new alternator.
I just forgot how much I love my tune and as far as I'm concerned tune > bass for the time being.

I'm sure some of its in my head bc like I said before I hate not doing things myself and at times can make things a bigger deal than they are
 
Just found it. The ebay store is called bnrparts and they sell the 200 amp alt for all gm trucks. Costs about $135 shipped give or take a couple dollars depending on your location.

Sent from my One X using Tapatalk 4
 
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