Growing up doesn't have to suck

[iamdub]

Dual muffler..... and a bypass. And a cutout , sharp !

Dual mufflers to quiet it down after losing the cats. The bypass has been capped cuz the cutout lost a butterfly valve and was staying open. Now it's just an oversized Helmholtz resonator. LOL

 

[iamdub]

I tested the level sensor on the original fuel pump module. Full was 40.x ohms, as it should be. As I slowly lowered the float arm, the impedance increased fairly smoothly until it reached a maximum of 193.8 ohms with a considerable amount of travel left in the float arm. Moving the arm further resulted in an open circuit for the rest of its travel. It's supposed to operate on a 40 ohms (full) to 250 ohms (empty).

193 is 77.2% of 250. 100% - 77.2% is 22.8%, which is a little under 25% or 1/4 tank. Just under 1/4 tank (per the gauge) is where it really started acting up when accelerating.

So, this means that when my gauge read ~1/4, I actually had anywhere from just under 1/4 tank of fuel to fumes remaining.

What I don't get is why the gauge didn't just suddenly plummet to "E" soon after that ~1/4 tank mark. Perhaps the PCM has backup logic to override the analog sensor in case of a failure? It could estimate the fuel remaining by factoring the last known quantity and injector duty cycle.

I guess I'm gonna have to fill one of my race jugs and go for a drive to see where it stalls. I could put three gallons in the jug and when the Tahoe runs out of fuel, that three gallons plus whatever is still in the tank should put the gauge right around the 1/8th tank mark. I'd know the accuracy of my gauge as well as my "stall point".

 

[adventurenali92]

@iamdub im looking to do the big three upgrade on my Nali, would that kit you linked work for my 2006?

 

[swathdiver]

I tested the level sensor on the original fuel pump module. Full was 40.x ohms, as it should be. As I slowly lowered the float arm, the impedance increased fairly smoothly until it reached a maximum of 193.8 ohms with a considerable amount of travel left in the float arm. Moving the arm further resulted in an open circuit for the rest of its travel. It's supposed to operate on a 40 ohms (full) to 250 ohms (empty).

193 is 77.2% of 250. 100% - 77.2% is 22.8%, which is a little under 25% or 1/4 tank. Just under 1/4 tank (per the gauge) is where it really started acting up when accelerating.

So, this means that when my gauge read ~1/4, I actually had anywhere from just under 1/4 tank of fuel to fumes remaining.

What I don't get is why the gauge didn't just suddenly plummet to "E" soon after that ~1/4 tank mark. Perhaps the PCM has backup logic to override the analog sensor in case of a failure? It could estimate the fuel remaining by factoring the last known quantity and injector duty cycle.

I guess I'm gonna have to fill one of my race jugs and go for a drive to see where it stalls. I could put three gallons in the jug and when the Tahoe runs out of fuel, that three gallons plus whatever is still in the tank should put the gauge right around the 1/8th tank mark. I'd know the accuracy of my gauge as well as my "stall point".

This might help some:

 

[iamdub]

@iamdub im looking to do the big three upgrade on my Nali, would that kit you linked work for my 2006?

It's pretty much a universal kit. One end of the three wires has the lug and heat shrink on it and you cut it to length and install the lug and heat shrink on that end of the wire yourself. On a GMT800, the battery and where the alternator cable goes is in the front left corner. So, there should be plenty of wire to go from the alternator to that positive lug, then from the positive lug to the positive post on the battery. You'd need an extra lug and some heat shrink, though.

 

[iamdub]

This might help some:

View attachment 279257

Excellent info! I never knew they had a chart that broke it down like that. I'll refer to that after my "manual gauge accuracy test" if something's amiss. Thanks, James!

 

[adventurenali92]

It's pretty much a universal kit. One end of the three wires has the lug and heat shrink on it and you cut it to length and install the lug and heat shrink on that end of the wire yourself. On a GMT800, the battery and where the alternator cable goes is in the front left corner. So, there should be plenty of wire to go from the alternator to that positive lug, then from the positive lug to the positive post on the battery. You'd need an extra lug and some heat shrink, though.

Thanks for the info. Gonna have to figure out how this is gonna work for me since I have neither the expertise to do this on my own, nor the audio shop nearby to connect everything for me.

 

[iamdub]

Thanks for the info. Gonna have to figure out how this is gonna work for me since I have neither the expertise to do this on my own, nor the audio shop nearby to connect everything for me.

It ain't nuttin' but copying the factory stuff. No expertise involved, really. If you can change out headlight assemblies and trim pieces, change engine oil, etc., then you can make and install the Big 3. Worst case is you'd have to buy or borrow something to crimp the lugs. You can use crimpers or a hammer style tool.

Example of hammer style: https://www.amazon.com/Compression-Crimping-Terminals-Tech-Team/dp/B0812CDCFD


Soldering isn't necessary. But, if you wanna solder them, you just need a torch, a spool of solder and pliers to hold the lug. I use Vise Grips to better my chances of not dropping the lug when it's full of molten solder.

I use a Coleman propane camp stove fuel tank with a Bernzomatic torch head:

 

[Sam Harris]

It ain't nuttin' but copying the factory stuff. No expertise involved, really. If you can change out headlight assemblies and trim pieces, change engine oil, etc., then you can make and install the Big 3. Worst case is you'd have to buy or borrow something to crimp the lugs. You can use crimpers or a hammer style tool.

Example of hammer style: https://www.amazon.com/Compression-Crimping-Terminals-Tech-Team/dp/B0812CDCFD


Soldering isn't necessary. But, if you wanna solder them, you just need a torch, a spool of solder and pliers to hold the lug. I use Vise Grips to better my chances of not dropping the lug when it's full of molten solder.

I use a Coleman propane camp stove fuel tank with a Bernzomatic torch head:

Agree! This is not difficult stuff. I have the kit in my cart.. to order later.. sometime in the near future.. you can definitely do it Chase..!

 

[adventurenali92]

Agree! This is not difficult stuff. I have the kit in my cart.. to order later.. sometime in the near future.. you can definitely do it Chase..!

Me and wiring DO NOT get along. Soldering... no thanks... I can see myself screwing that up the minute I try it.