79K5Thumper

I've been looking for a straight answer for weeks, and have yet to find anything so I'm asking here. Where are you LSX swappers putting the fuel tank pressure sensor? Are you just drilling a hole in the top of you fuel tank big enough for the sensor grommet? I don't want to totally hack my brand new TBI fuel tank, nor do I want a custom tank or to utilize a tank from another vehicle, nor do I wish to use the LS fuel sender (that has the hole drilled for the fuell tank pressure sender). How are you guys installing it in your swaps? Are you putting a new hole in the tank, or are you some how mounting the sensor in the EVAP line? If you are, can someone give me an idea how to do it? I have all the smog and evap equipment, I just need a place to put the damn fuel tank pressure sensor

Any advice/links/direction/pictures would be MUCH appreciated, I pretty much have everything else nailed out! Thanks everyone!

reedld

iTrader: (7)

Why are you using the evap sensor? Is it local laws or is the swap into something new? My fuel evap was removed from the PCM. Is this going in an older K5?

gofastwclass

iTrader: (2)

Unless emissions testing is a requirement where you live, I would save yourself the headache and skip stuff like the entire EVAP system. You'll simplify the installation and it can all be removed from the calibration by a savvy tuner without any negative effect.

ls1nova71

iTrader: (4)

You cant just drill a hole in the tank and put the sensor in it or it will leak. The tank is too thin, it would need to be about a half inch thick to seal, thats what the original plastic sender is. You can put it in a hose and hook the hose to a nipple on the tank that isnt being used or the line going to the purge solenoid.

79K5Thumper

That's an awesome idea, thanks! This is probably exactly what I'm going to do!

The reason I'm using the fuel evap system is my K5 is a 1979, I live in Southern Comifornia and my $mog guy bumped up his prices due to how strict they're getting with emissions. It once cost me $300 bucks to smog a 1993 Chevy Dually with a 454. No cat converter, a misfire, and a clogged EGR, and not only did she pass the sniffer better than my moms V6 Charger, but the tech told me it was some of the lowest numbers hes ever seen, aside from vehicles with active fuel management (shutting off half the cylinders when cruising). Sure do miss that old rat, but my Duramax feels the void nicely. The smog ref gave me a bunch of bs about having to use a stock LS donor tank, or having a custom tank built to closely match size and shape, but I KNOW there's PLENTY of people with smog-legal LS swaps without using the tank from their LS donor vehicle. My 2003 engine and EVAP set up only has the pressure sensor and the evap tube in the sender, no other connections at the tank, so I'll probably use a T fitting and tap the sensor in as described above. This is awesome news, I'm finishing the planning stages on my swap as well as my friends, though he has opted to reg his K5 in LHC, AZ at his vacation house. Bastard, lol.

Truckmechanic1983

Yup just epoxy the pressure sensor to a barbed tee and put it online to the charcoal canister you will have to use the oem canister and vent purge selinoid and also do some trickery to get the readiness moniter to set for the evap mine passed first shot through riverside county

79K5Thumper

Glad to hear it! I'm in Ventura County, what kind of trickery should I expect to have to pull?