What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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j91z28d1

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guy at work has a 08 truck with the 4.8 in it. tapping like crazy, heard it across the parking lot at 430am. I walked over to talk to him, he's like it's been like that forever. revs it up and it goes away, idles for a bit and starts tapping again. 200k and he says the truck 4.8 never had the afm. truck didn't even have oil pressure gauge on the dash and he's never looked. just when it gives up its going to the junk yard. not worth fixing.


kinda wild just drive it around tapping. he said it sometimes goes away for months at a time and then comes and goes.
 

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guy at work has a 08 truck with the 4.8 in it. tapping like crazy, heard it across the parking lot at 430am. I walked over to talk to him, he's like it's been like that forever. revs it up and it goes away, idles for a bit and starts tapping again. 200k and he says the truck 4.8 never had the afm. truck didn't even have oil pressure gauge on the dash and he's never looked. just when it gives up its going to the junk yard. not worth fixing.


kinda wild just drive it around tapping. he said it sometimes goes away for months at a time and then comes and goes.
lol, my 03 silverado that I sold to my sister does the same thing 284k+ on it, taps at idle after sitting for a minute and comes and goes usually months at a time, it's good truck, she refuses to sell it back to me.
 

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Wes
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Rank amateur here but is it possible the ecm is misreading the MAF input?
dealer said they took a look at it has high exhaust pressure, suspect 3rd cat is clogged, so they said get that looked at and put the stock airbox back on it and bring it back and then they can get more accurate readings
 

Writefast

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dealer said they took a look at it has high exhaust pressure, suspect 3rd cat is clogged, so they said get that looked at and put the stock airbox back on it and bring it back and then they can get more accurate readings
Hopefully that fixes everything.
 

j91z28d1

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lol, my 03 silverado that I sold to my sister does the same thing 284k+ on it, taps at idle after sitting for a minute and comes and goes usually months at a time, it's good truck, she refuses to sell it back to me.


I'm surprised they last so long tapping like that.
 

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