Throttle Response Issues (Video)

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Sarge

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09 Yukon. Throttle response has always been poor but here recently coming back down to idle has been very laggy (see vid). Truck has a cold air intake on it and yesterday I added a tb spacer (free) and ckeaned the filter, maf and cleaned the throttle body also while it was off and seafoamed the top end and unhooked battery for a “relearn”. I’ve tried fuel cleaners, 93 fuel, stock and even with a tune loaded off my bully dog still does it

Vid

Normal? Suggestions?
 

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Wes
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doesn't seem all that bad to me, but if it were me I would take the serpentine belt off and start it up and see it that makes any difference then you know if it is a accessory or not. i.e. bad tensioner pulley, alternator, power steering.
 
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Sarge

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Any of those will make the throttle response poor and back to idle slow?
 

PG01

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There is an idle relearn procedure, disconnecting the battery doesnt do it. You are supposed to do it right after cleaning or reinstalling tb. Although I remember i read that if you you don’t do it immediately now you have to drive a while a different speeds for a few days, weeks and it will ‘relearn’ that way. Give it some time. Ill see if i can find the procedure
 

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Wes
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Any of those will make the throttle response poor and back to idle slow?
I don't know it was just theory to try if everything else was good, you stated it has always been poor performing to me it looks pretty normal but it might not be, I personally upgraded mine to a ls7 throttle body because it is a tiny bit larger 90mm and I think the design is better and I didn't think my original was working 100% either it didn't seem slow but it seemed more like it sputtered more than it should, since I changed it out it has only sputtered once and that was just last week after being on there for atleast 6months I will probably give it a good cleaning here soon with a motor detail.
 
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Sarge

Sarge

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I will try the relearn. Idle is fine, its just the rev up and rev down is super delayed and slow. If tap the gas at idle in park it doesn't just rev up and drop back down it hangs and slowly comes down like in the vid. Is that normal? My buddies 2013 5.3 Sierra doesn't do it.. but he has 29k miles and im at 175k. Does the motor go week in the throttle body?
 

Meccanoble

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If you moved plate for throttle body, most likely you will need a relearn but when I needed one, the rpm's would stick far worst before improving. I'm sure its probably not related but I think I seen an improvement when I replaced my brake switch (same that controls cruise control). Maybe try unplugging/disconnecting/reconnecting? Just adding a free quick check option. If your cruise control doesnt work, would be a good idea to look into replacing.

My truck took forever to fully relearn and was never the same until I replaced my switch. Could have been crazy coincidence but my cruise never worked since I owned truck.
 
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Sarge

Sarge

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If you moved plate for throttle body, most likely you will need a relearn but when I needed one, the rpm's would stick far worst before improving. I'm sure its probably not related but I think I seen an improvement when I replaced my brake switch (same that controls cruise control). Maybe try unplugging/disconnecting/reconnecting? Just adding a free quick check option. If your cruise control doesnt work, would be a good idea to look into replacing.

My truck took forever to fully relearn and was never the same until I replaced my switch. Could have been crazy coincidence but my cruise never worked since I owned truck.

Ok, yea I had to put a new switch in it last year because cruise stopped working. Ill take a look and double check
 

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