Illegal Vette

I've installed an LS1 in my '82 Vette, and all that's left to do is get it through emissions testing but I still have to figure out how to wire the fuel level input on the PCM. I could install the entire fuel pump and sending module, but I'd really rather not modify my gas tank and I'm not even sure my gas gauge would be compatible. Have any of you solved this problem?

1964SS

iTrader: (1)

If you've still got the factory tank and gauge why even mess with it? I would use the original fuel level sender system.

Illegal Vette

If I don't give the PCM an input for fuel level it will set an EVAP code.

69 Ghost

It can be done. I assume you are using a 411 PCM. You will still have to program the PCM to output the fuel gauge and hook up a wire for the output. You will then need to calibrate the PCM for whatever you are using. Again I assume it is a 0-90ohm setup......

Illegal Vette

Well that's encouraging! So I'll be needing software sooner than I thought, I was thinking HP Tuners. Which pinout from the PCM will drive the fuel gauge?

Bilster

iTrader: (21)

When you get your HP Tuners, just turn off the EVAP code.....or have a mail order tuner do it for you. It's so simple that I wouldn't think it would cost much. Turn off all other unnecessary codes while you are at it. VATS, after cat oxy sensors, etc.

Illegal Vette

I did have those things turned off for my initial start up, although the tuner told me that the PCM continues to do them, it's just the the MIL is no longer illuminated. A scanner will reveal whether they work or not and they have scanners. They MUST be functional in order to be emissions legal here. And I've installed the fuel pressure sensor and am installing secondary air etc. Really other than how to wire the fuel level sensor the rest is pretty much done although I will have to figure a way to mount the air pump. I've just been looking at the PCM pinouts and don't see any that look like they would connect to the fuel gauge.

Bilster

iTrader: (21)

Colorado must be more stringent than New Mexico. In New Mexico, the emissions machine plugs into your EDL port. If your PCM is not producing codes, then that portion of the test is complete. The rest of the test includes a visual on your cats and a check of your gas cap.

Illegal Vette

I have to have it certified by an emissions referee that works for the state of colorado. If everything that came on a 2002 camaro is in place and functional, and there are no codes he'll give me paperwork to present to the emissions testing center, and if it passes emissions test on the dyno I'm good to go. I wired up the fuel pressure sensor today, and hooked up the gas gauge to terminal J on connector 230. We'll see if it works, the gas gauge is 90 ohms which is different than the 2002 camaro, but it should give it some kind of input.

garys 68

iTrader: (1)

Yeah, IIRC GM changed the range of the senders with the LS motors from 0-90 ohms to 40-250 Ohms. If the original sender doesn't work, you could just wire in a 100 ohm resistor.

Illegal Vette

I've read that if the PCM doesn't sense change in the resistance that it will set a code, but we'll see.

69 Ghost

PM me I can get you setup with a tune and the wiring....

bczee

iTrader: (12)

I saw a swap once that the guy used a stock fuel sender from the donor. It was removed from the sender bucket. He connected the level sender as you should, manually set the fuel level arm so the PCM would receive a signal and just manually adjusted it as needed to past the test and then hid the sender.

Might hide it under the seat and just reach under and move the arm to represent the correct fuel level as the old gauge is displaying.??

Not telling you to do it. But just saying what I saw as a way someone pasted the test by doing. .LOL..

I would think there are ways to modify the old sender by replaying it with the new inners ? I also recall one of the vendor saying that they had old sender with new and correct ohm inners. That would be the best solution.. Sorry, don't recall which vender said that before.

BC

Illegal Vette

That's hysterical! I sure hope it doesn't come to that.