Notices
86-95 Trucks & 4Runners 2nd/3rd gen pickups, and 1st/2nd gen 4Runners with IFS

Low Fuel lamp on with a full tank

Thread Tools
 
Search this Thread
 
Old 08-06-2009, 07:24 AM
  #1  
Registered User
Thread Starter
 
jbt308's Avatar
 
Join Date: May 2004
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Low Fuel lamp on with a full tank

Hello,

I've got an 1988 4Runner SR5 and I noticed this morning that the low fuel light came on with the gauge reading 3/4 full. I recently replaced the fuel pump in the tank and it's been working like a champ.

Thinking the gauge might've broken, I pulled in to fill up, and could only get 8 gallons in the tank. I'm thinking the sending unit might be broke. Any ideas on where the issue might lie?

Thanks,
Old 08-06-2009, 09:25 AM
  #2  
Contributing Member
 
TNRabbit's Avatar
 
Join Date: Apr 2006
Location: TENN Native Languishing in Virginia
Posts: 4,787
Likes: 0
Received 34 Likes on 14 Posts
You're lucky; I've NEVER seen the fuel light work on any of these trucks!
Old 08-06-2009, 09:57 AM
  #3  
Registered User
 
Erik Beeman's Avatar
 
Join Date: Nov 2008
Location: Concord, CA
Posts: 433
Likes: 0
Received 1 Like on 1 Post
My fuel light doens't work on either of my trucks, my 88' nor my 92'
Old 08-06-2009, 10:13 AM
  #4  
Registered User
Thread Starter
 
jbt308's Avatar
 
Join Date: May 2004
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
One other odd thing is that the fuel gauge stays at 3/4 full. But I filled up the tank this morning?
Old 08-06-2009, 03:31 PM
  #5  
Registered User
 
joesscamaro's Avatar
 
Join Date: Sep 2008
Posts: 43
Likes: 0
Received 0 Likes on 0 Posts
Still learning about Yotas, but maybe a fuel level sensor? I had mine go bad in my Sonoma...don't know if they're the same tho.
Old 01-02-2011, 11:30 AM
  #6  
Registered User
 
Jeff B. in Michigan's Avatar
 
Join Date: Jan 2003
Location: Southwest Michigan
Posts: 134
Likes: 0
Received 0 Likes on 0 Posts
Kind of old thread but ... yesterday ... after 193K miles, my low fuel lamp has started to fail. The specific issues I am experiencing are:

1) lamp flickers with road bumps (like something is shorting out) after filling up the tank.

2) between 1/2 and 1/4 the lamp comes on fully (when operating correctly, it came on at 1/8 tank)

The fuel gauge seems to be working fine.

Anyone else experience this issue and find a solution?

Thanks,

Jeff
Old 01-02-2011, 01:35 PM
  #7  
Contributing Member
 
hilandfrog's Avatar
 
Join Date: Dec 2002
Location: Helena, Mt.
Posts: 389
Likes: 0
Received 0 Likes on 0 Posts
Didn't know the truck had fuel idiot light....



Repo
Old 01-03-2011, 10:21 AM
  #8  
Registered User
 
Hadmatt54's Avatar
 
Join Date: Oct 2005
Location: New Brunswick, Canada
Posts: 578
Likes: 0
Received 2 Likes on 2 Posts
One other odd thing is that the fuel gauge stays at 3/4 full. But I filled up the tank this morning?
Does your fuel gauge drop below 3/4 as your tank level drops? I ask that because, it sounds like you have a partial ground in your circuit , causing the fuel light to come on and the fuel gauge to stay at 3/4.
The low fuel level switch is a type of variable resistance. You test it with a 3.4 w. bulb and a 12v. source in series with the switch. When it is out of liquid the the 3.4 w. bulb lights, immerse it in liquid and the bulb goes out. You test the gauge in the dash the same way 12v in series with the 3.4 w. bulb and the fuel gauge should go to about the 1/2 mark.
Old 01-04-2011, 01:56 AM
  #9  
Registered User
 
Jeff B. in Michigan's Avatar
 
Join Date: Jan 2003
Location: Southwest Michigan
Posts: 134
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Hadmatt54
Does your fuel gauge drop below 3/4 as your tank level drops? I ask that because, it sounds like you have a partial ground in your circuit , causing the fuel light to come on and the fuel gauge to stay at 3/4.
The low fuel level switch is a type of variable resistance. You test it with a 3.4 w. bulb and a 12v. source in series with the switch. When it is out of liquid the the 3.4 w. bulb lights, immerse it in liquid and the bulb goes out. You test the gauge in the dash the same way 12v in series with the 3.4 w. bulb and the fuel gauge should go to about the 1/2 mark.
Thanks for the information. The gauge in dash still works, the only problem is relating to the low fuel lamp!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
jbv808
86-95 Trucks & 4Runners
16
08-06-2021 04:47 PM
Eggslinger
86-95 Trucks & 4Runners
22
06-08-2019 03:32 PM
Doug4320
86-95 Trucks & 4Runners
19
03-24-2018 10:11 PM
redneck17
86-95 Trucks & 4Runners
8
07-17-2015 07:44 PM
skoti89
Offroad Tech
3
07-08-2015 12:05 AM



Quick Reply: Low Fuel lamp on with a full tank



All times are GMT -8. The time now is 04:27 AM.