Fuel gauge not working

Reply Subscribe

Thread Tools

Search this Thread

Jun 5, 2024 | 12:40 PM

Phil Fleming

Thread Starter

Cross-Country

Joined: Jun 2016

Posts: 67

Likes: 5

From: Mount Forest Ontario

Fuel gauge not working

Hello,
Looking for a little help. My fuel guage is not working properly. When I ground the wire for the gauge it reads full. I pulled the sending unit and it was non functional so I purchased a new Dennis Carpenter sending unit. It reads 13.6 to 95.7 across its range. When I fill the tank it won’t read more than half full. Any thoughts? Possibly the IVR? The temp gauge reads.

Jun 6, 2024 | 08:47 PM

manglass

More Turbo

Joined: Feb 2004

Posts: 704

Likes: 40

Is the float mechanically restricted? You could take the sending unit out of the tank and run the float through its travel and see what happens with the gauge. I think the gauge works with 10-70 IIRC so those readings don't sound too bad. If you want to check the IVR: instead of just grounding that wire, ground it through a test light and the light should blink while the gauge slowly rises to full.

Lou Manglass

Jun 7, 2024 | 08:17 AM

Phil Fleming

Thread Starter

Cross-Country

Joined: Jun 2016

Posts: 67

Likes: 5

From: Mount Forest Ontario

Thanks Lou. The floats travels freely in my hand. I will try the test light.

Jun 7, 2024 | 08:51 AM

FuzzFace2

FTE Legend

Joined: Nov 2015

Posts: 30,886

Likes: 4,119

From: Angier, NC

Quote:

Originally Posted by Phil Fleming

Thanks Lou. The floats travels freely in my hand. I will try the test light.

I think he meant sender out of tank, with the wire hooked to the sender and it grounded if you move the arm dose it read right then?

Is there something in the tank the float or arm is hitting keeping it from moving all the way up?
Dave ----

Jun 7, 2024 | 04:33 PM

manglass

More Turbo

Joined: Feb 2004

Posts: 704

Likes: 40

Sorry to be so brief but thank you, FuzzFace2, you're on the right track.

There seems to be an epidemic lately of sending units that are incorrectly oriented so they bump into the tank instead of free floating.

Lou

Jun 11, 2024 | 01:23 PM

Phil Fleming

Thread Starter

Cross-Country

Joined: Jun 2016

Posts: 67

Likes: 5

From: Mount Forest Ontario

So to update, today I pulled the sending unit and while holding it in my hand the tank will read 7/8 full which would be close enough for me. I put the test light on the guage wire and it gives a pulsing light. There are no obstructions in the tank as far as I can tell and the float seems to not have any binding. When I re-installed the sending unit it still only read 1/4 tank when there is close to 3/4 tank.

Jun 11, 2024 | 09:13 PM

MARC

Tuned

Joined: Sep 1999

Posts: 436

Likes: 32

From: Sonoita

Gas tank

Out of curiosity I would run a designated ground wire to gas tank sensor and see if your readings change. Or check the o resistance from ground wire or housing on tank to a good ground and see if it changes