06 LQ9 to 89 Burb- CA legal

[socoinslo]

So as the title implies, Im going to swap a LQ9 in my 89 suburban. I want to make it CA smog legal which makes it a little more difficult. Probably most ppl on here dont usually deal with smog issues, but Ill post here anyways.
what I need to do s get the Evap system from the engine donor vehicle (2006 GMC Sierra 1500 Denali AWD) installed and properly functioning in my suburban. To my knowledge, the main components to the evap system are:
Charcoal canister
canister vent valve
Purge solenoid/valve
fuel tank Vent solenoid/valve
fuel tank pressure sensor

Right now, I think that the easiest way for me to get all these components in my truck is to swap my fuel tank for a 99 suburban or Tahoe fuel tank. This tank will have provisions for the vent solenoid and will accept the newer style sending unit which includes the tank pressure sensor. Looking at pictures of the 99 tank though I am a little confused about what the third hole in the tank is for (picture below) one for the sending unit, one for the vent valve, and ?

 

[K85 Octane]

Only guessing:

Supply
Return
Pressure
Vent valve
Filler

Only a total guess though lol. Sounds like a challenge. It will be awesome when it's done but you will need a lot of patience. (and hopefully a nice SMOG Referee)

 

[dhcomp]

Curious to see how are you going to do all this.

If i ever get around to a swap, it will have to be CA legal.

That being said, are you sure all that has to be swapped? A lot of that is stock on the 89 too. Never heard of ANYONE having to swap the tank for a newer style.

 

[socoinslo]

In order for the evap system to actually function properly the ecm needs to know the pressure in the tank and the fuel level. For the computer to run its evap test it will want to know that the vehicle is moving at a certain speed and that there is a certain amount of fuel in the tank. If the right conditions are met (I think its something like 65 mph and 3/4 tank of gas) then the computer will close the vent valve and open the purge valve and check that the tank holds pressure (vacuum in this case). If the everything functions properly then the system check completes, if not, it throws a code and lights the MIL. This is my understanding of it. The old style tank doesn't have provisions for the pressure sensor and the old style float doesn't send the right signal for the computer, so I think the easiest way to get the right sensors in the tank is to swap to the newer style sending unit which has both. I agree that it doesn't seem like ANYONE is having to mess with all this CA B.S. except for a couple people on ls1truck.com . I just don't want to go through all the trouble of swapping my fuel pump in my old tank and plumbing my fuel lines to it, and then not passing the BAR inspection. What I ended up doing is just cutting the pieces I needed off the newer style tank and welding them to the older tank, now I can use the newer style sending unit and I have the mounts for the vent valves. I am VERY open to other suggestions though... that is why I started this thread

 

[socoinslo]

There are also different evap systems and components for different model years. Mine being a 2006 motor means that I also have to deal with the ORVR. I think ha ha

 

[dhcomp]

Have you talked to a referee?

I wonder if this part of the system even comes into question, if the balance of the underhood smog stuff remains.

I'm sure this part could be programmed out, and who knows how knowledgeable the ref's are.

Might be worth a pre-swap meeting with a ref to feel out the situation. Act dumb and don't ask too many specific questions.

 

[socoinslo]

it is a possibility that I could maybe "get away with it" depending on who actually inspects it. But, I have heard from a couple people that they will definitely check the system. When I asked a ref, he said that they will check it.
My computer is currently set to not turn on the MIL if the system check does not complete, so it is essentially off, but I still want to have all the components there and in place so that the referee will atleast see that they are there. I will eventually KNOW for sure what will and what wont work LOL

 

[NorCalAnthony]

Subscribed

Good luck with your swap. I'm planning a similar project with my '89 Blazer so I'll be watching to see what all you'll have to do/go through for when my time comes.

 

[sreidmx]

If there is a readiness monitor that exists for it they will look and if it's incomplete they will fail you. You gotta figure out a way to set it to ready/ complete.

 

[NorCalAnthony]

socoinslo - did you ever finish your swap and get it refereed? Curious to see how everything went...