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Fuel gauge interface module

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FRANKENBURBAN
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I'm sure I'm not alone with the infamous bouncing fuel gauge that goes all over the place whenever you hit the throttle, brakes, go around a turn, and so on. I replaced my sending unit with one of the metrum rods a few years back when it first started, but this didn't stop the problem. GM used to offer a fuel damper module under a TSB that you could install to stop this, but they have discontinued it LONG ago, and ALL stock of them is LONG GONE!(I checked, I can't find one ANYWHERE for the 0-90 ohm sender) Many have resorted to filling the air core motor in the cluster with 30K weight silicone fluid to stop the hummingbird effect, and to slow it's movement so the sloshing isn't so noticeable, and even some have resorted to trying to install capacitors and resistors to try and average out the fuel gauge reading without much success(I'm the guilty one of this)

I was about to give up on this problem that irritates me to no end, but I just stumbled across a solution tonight. A company called SPEEDWAY MOTORS makes a fuel gauge interface module that installs between your sender and gauge, and can be calibrated to work any gauge with any sender(it was made for the classic car market so they could use the old style senders with modern style gauges). It has an anti-slosh feature built into it to stop the dancing fuel gauge, it is set up so you can calibrate teh empty and full points to where you want them on the gauge, and it also has a driver in it to power up a low fuel light(it is a VERY low amp driver, and says it can either power a relay to turn on an incandescent bulb, or power a small LED, but nothing more). With a set of dip switches and an adjusteable reostat, you can set it to MANY different style of sending units(the GMT-400 trucks is 0-90 which is an oddball as GM had switches to 40-240 ohm for many of ther other vehicles of this era, hence why we can't use the S-10 or van fuel buffer module, I tried, wouldn't work), and then go in using the same dip switches and reostat adjust teh empty and full points on the gauge itslef. Seems like a nice product, and I will be ordering one here shortly to try it out when I do my ESCALADE cluster swap as all of the reviews on it are all 5 stor with no bad reviews of it anywhere I looked.

http://www.ebay.com/itm/Fuel-Gauge-...ash=item3cf8bb5c35:g:YqAAAOSw9N1VvTeL&vxp=mtr
 
Did you ever get this accomplished? My 95 C3500HD needs some anti-slosh help as well. Id like to get my hands on on of those oem dampers just to see what it consists of (goes in the tank I think) but it seems like thats not gonna happen...
 
When the fuel gauge quits bouncing (moving) then I know I am for sure about to run out of fuel!

IMO it's a feature and complaints about gauges actually moving and showing one stuff is why we now have all the numb "idiot light" gauges. May as well leave them off and replace them with a Low fuel light, high temp, low oil pressure, etc. With as numb as Model Year 2000+ gauges really are this has more or less happened. The computer controlled oil pressure gauge on the Dodge Diesel is a work of useless as all the engine has is a switch. :facepalm: It takes several min for adding fuel to show up on the numb Dodge gauge if I fill with the engine running... Duramax engines also have buffered temp gauges...
 
My 69 camaro never bounced like any of my gmt400 pickups. So it’s not a new thing to eliminate it. The delay on my ‘01 suburban and ‘10 escalade dont bounce. From dead empty I fill up (wife’s rig so empty is how she does it) to 100% full takes less than 2
Seconds to read full and computer to calculate miles till empty again.
2 seconds is very acceptable to me over havin a gauge bounce around.
 
I have the aftermarket one and a factory one out in my shop. The factory one I have worked with a gas sender not a diesel, so it never got hooked up. The GM tsb ones are all gone now, and I never found any info on replacement parts to build one. I tried the 30K weight silicone in the gauge itself. It worked for awhile, but it has eventually resumed doing it. I need to wire in the speedway module, but with my health being so bad lately, I hardly drive it, so it hasn't been a priority. I don't even drive 5k miles a year right now, so a bouncing fuel gauge hasn't bern much of a concern.
 
...it’d be nice to get hands on one of those upgrade units for some reverse engineering. I’d be happy just to see pic of one! With so many manufacturers using buffer modules, shouldn’t be too hard to figure out how to build one.
 
Most did use the ecm did by the late 90’s, but GM, Ford, and VW at the very least built vehicles with seperate signal buffer units. The GM upgrade unit that’s no longer available went in the tank, I think. So it couldn’t have been very big.
 
The GM add on was a buffer module that you added into the wiring between the cluster and sender. There was never anything that went in the tank. Starting in 98 for gas trucks, GM sent the fuel gauge signal through the pcm. Diesels didn't get it because the diesel ecm wasn't capable of it. Some diesel vans got an inline buffer according to diagrams I've found, but I haven't been able to find any part numbers for them. I have one of the inline buffers that were used for 97 on gas trucks, but it was for a 33-240 ohm sender, and diesels are 0-90 ohm. I also tried some different capacitors, but none worked very well across the gauges sweep. I need to get out and mount the speedway box to take care of mine.
 
I thought the TSB unit thats now discontinued went in the tank in place of the sender/resostat? The buffer box on a 97 S10 is not real simple from what I can see but Id guess theres a way to rebuild it to work 0-90ohm. Thats above my head...and likely more money than the speedway box anywho!
 
Those TSB units were specified for full size 4 door SUVs. Why not 2 door? Why not pickups? Did they not have the same problem? A buddy has an early 97 4dr Tahoe and his gauge is all over the place. I have an early 97 pickup and its steady as a rock! My fuel sender is the threaded type but his is the newer quick-connect style. My 95 HD bounces all over the place but I just (previously) marked that up to a junky aftermarket sender.
 
I thought the TSB unit thats now discontinued went in the tank in place of the sender/resostat? The buffer box on a 97 S10 is not real simple from what I can see but Id guess theres a way to rebuild it to work 0-90ohm. Thats above my head...and likely more money than the speedway box anywho!
No, it did not replace the sender. It was actually the same module as the S10, but a different board to work with a 0-90 ohm sender, and it did not require the 5 volt reference supply. Some 97's had a buffer just like the S10's had according to some part numbers I have found surfing rockauto and acdleco, but I couldn't find any info in alldata or GM service manuals about them. The speedway motors looks to be the only available option right now short of building your own, or using an arduino setup.
 
Wonder what ohm sender my 97 has? Its an early production unit so its like a 96 instead of full OBDII like a 98 and my gauge doesnt bounce. Maybe I have the buffer and dont know it! I have the factory service manuals but if you couldnt find it on alldata, its probably not in the manual either. The S10 was under the dash. Ill look around my rig and see what I find. Any suggestions are welcome.
 
All diesel pickups used a 0-95 ohm sender in the tank. Starting in 98 all gassers changed to the 33-240 ohm sender, but diesels stayed 0-95 ohm. Rockauto and acdelco lists 2 different buffer modules for a 97 pickup. Wether they actually haveone or not, I don't know.
 
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