L86 to L8T in '19 Yukon XL Denali

[chevman88]

Is the L86 throttle body smaller than the L8T's throttle body?

They look to be the same size, just figured I would try and use the newer one.

Took it out for a test drive this afternoon, can definitely feel the torque difference. Brakes work just as well as they did before. Got the codes narrowed down to p0443 and p0458 which are both evap related (the one connector I managed to break) and a sporadic p2534 for ignition circuit low.

Planning on reseating the purge valve as I transplanted it from the L86 intake to the L8T and verifying the connector has good readings.

For the ignition circuit I'm not sure as it's sporadic, but I'll start by verifying I reattached all of my grounds.

 

[chevman88]

Figured out the evap codes, one of the pins was bent and wasn't seating where it should, was able to bend it back and it looks like those codes are gone. I've got some misses at idle still, so I'm going to swap all of the L8T coils on since they're newer (wires and plugs are new)

 

[L8T BURB]

How is the tune coming along? Wonder if some revisions of the tune could smooth out the issues at idle, or do you think it is a mechanical defect?

 

[B-train]

What did you use for a tune? I'd assume you could just get a base map from an HD pickup and then copy and paste the corresponding tables in for spark, fuel, etc. I'm relatively new at tuning my own stuff......it's way different than a test cell full of all kinds of gadgets. Keep us posted. This is awesome!

 

[chevman88]

How is the tune coming along? Wonder if some revisions of the tune could smooth out the issues at idle, or do you think it is a mechanical defect?

Still couldn't get ahold of Kevin, but I think I found one of his tunes posted on the hptuners forum that I copied the fuel and spark tables from. I need to schedule some dyno time to actually get it tuned.