Vortec 454/4L80e HD swapped 1999 Tahoe OBS

[bigfootchiro]

Does anyone know what this hose is called? It connects right behind throttle body on passenger side into valve cover. It isn’t seating properly in valve cover or intake. Can’t seem to find it anywhere online, and parts stores can’t figure it out.

 

[swathdiver]

My LTFTs at idle go up too when idling a while. Sometimes even into the high teens but once underway and at a steady speed they'll return to zero. So don't yet to be concerned about Bank 1, but do find that problem with Bank 2. Minus 25 is usually a massive vacuum leak, or maybe an exhaust leak of some kind on that side.

 

[swathdiver]

Does anyone know what this hose is called? It connects right behind throttle body on passenger side into valve cover. It isn’t seating properly in valve cover or intake. Can’t seem to find it anywhere online, and parts stores can’t figure it out.

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That would have to be some part of the pcv system no?

 

[bigfootchiro]

That would have to be some part of the pcv system no?

That’s what I thought, but no one can find the part. I’ve seen 6.0 and 5.3 call it something like a Fresh Air Hose, but can’t find it for the 454

 

[swathdiver]

That’s what I thought, but no one can find the part. I’ve seen 6.0 and 5.3 call it something like a Fresh Air Hose, but can’t find it for the 454

http://www.irv2.com/forums/f22/positive-crankcase-ventilation-62121.html

See if you can find a VIN for a truck that came with that motor and run it through AC Delco's website.

https://parts-catalog.acdelco.com/catalog/catalog_search.php

Do you know the RPO and year of that motor?

 

[bigfootchiro]

http://www.irv2.com/forums/f22/positive-crankcase-ventilation-62121.html

See if you can find a VIN for a truck that came with that motor and run it through AC Delco's website.

https://parts-catalog.acdelco.com/catalog/catalog_search.php

Do you know the RPO and year of that motor?

I don’t know the RPO, but it’s a 1998. There’s an error in the VIN number somewhere too, just can’t find it

 

[swathdiver]

I don’t know the RPO, but it’s a 1998. There’s an error in the VIN number somewhere too, just can’t find it

Ok, I reckon it's an L21 which was the commercial version of the L29 Vortec 7400. Forged crank and pistons. So now you need the book on the L21 and then you can find that part or at least know where to look for it in boneyards. It was used in those P12/W-20 chassis you pulled it out of and the Kodiak, Topkick and H-Series Isuzu.

 

[bigfootchiro]

Ok, I reckon it's an L21 which was the commercial version of the L29 Vortec 7400. Forged crank and pistons. So now you need the book on the L21 and then you can find that part or at least know where to look for it in boneyards. It was used in those P12/W-20 chassis you pulled it out of and the Kodiak, Topkick and H-Series Isuzu.

It came out of a P30 chassis, and I did find the VIN! It’s VIN J, but don’t know if that specifies L21 vs L29. Still can’t seem to the part through AC Delco. I’ll look into the P21 and see if it matches up. Anywhere I can find the RPO codes online with the VIN? GM wants $50 to do the build sheet

 

[Tonyrodz]

It came out of a P30 chassis, and I did find the VIN! It’s VIN J, but don’t know if that specifies L21 vs L29. Still can’t seem to the part through AC Delco. I’ll look into the P21 and see if it matches up. Anywhere I can find the RPO codes online with the VIN? GM wants $50 to do the build sheet

Why so much?

 

[bigfootchiro]

So it is an L29 block. The L21 did come in the P12 chassis, but it has a coil near plug distribution, which mine doesn’t have.