Approach to fuel sending unit in '88 4Runner
12-25-2009, 06:36 AM
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Approach to fuel sending unit in '88 4Runner
The fuel sending unit in my '88 4Runner SR5 works at the upper range, i.e., when tank is filled it works fine until about 90 miles driven then drops to empty. The low fuel light works fine. I wanted to pull the sender and see if the problem is fixable. Do I have to drop the gas tank or is there an easier approach to removing the fuel sending unit?
12-25-2009, 07:28 AM
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There is an access panel under the PS rear seat. Fold it forward and it should be under there. Just make sure the tank is fairly empty to avoid spillage.
12-25-2009, 12:43 PM
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The access panel under the rear seat will let you pull the fuel pump, but the fuel sender is in a different place, and you will have to drop the tank to replace it.
Have your replacement sender handy, because the wire wound resistor is broken from all those years of being rubbed by the wiper arm that's attached to the float arm.
When the wiper is contacting the resistor above the break [full tank] the gauge will read. As soon as the fuel level drops and the wiper contacts below the break, the gauge drops to zero.
Have your replacement sender handy, because the wire wound resistor is broken from all those years of being rubbed by the wiper arm that's attached to the float arm.
When the wiper is contacting the resistor above the break [full tank] the gauge will read. As soon as the fuel level drops and the wiper contacts below the break, the gauge drops to zero.
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12-25-2009, 05:21 PM
#8
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Not on first generation 4Runners and similar pickups.
On the OP's '88 4Runner, the fuel tank is like this:
The fuel pump is accessible through the panel under the seat, but the sender and the low fuel warning sender [which are together in the same assembly] are only accessed by dropping the tank.
On the OP's '88 4Runner, the fuel tank is like this:
The fuel pump is accessible through the panel under the seat, but the sender and the low fuel warning sender [which are together in the same assembly] are only accessed by dropping the tank.
Last edited by myyota; 12-25-2009 at 05:25 PM.
12-25-2009, 06:19 PM
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I must say; a perfect thread. fully persuaded like Jesus, completely resolved, with pics, and definitive information on year model changes. Devestatingly accurate for some, to the point of near insanity, but you now know what must be done- Like Colonel Kurtz. Mine is running perfect, but i will have no questions, if a a prob arises , in the future.
A big Kudos, and warm nog and toilet paper goes out to myyota
and yota4runna...
A big Kudos, and warm nog and toilet paper goes out to myyota
and yota4runna...
05-12-2010, 05:07 PM
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05-13-2010, 05:07 PM
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05-14-2010, 05:15 AM
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The only way that one will work is if you add the autometer fuel gauge that goes with it.
The resistance of that sender is 33 ohms (full) to 240 ohms (empty). The resistance of a Toyota sending unit is 3 plus 2 or minus 3 ohms (full) to 110 plus or minus 7.7 ohms (empty). Basically any ohmic readings from 0 to 117.7 ohms (full to empty) on a Toyota sending unit are within spec. In my area there is a outfit that sells new gas tanks and parts as well as used tanks, gauge sender assemblies, etc. that come from southern (non rust climate) vehicles. See if there is a company like this near you. That would be your best bet, I doubt if you would ever find one at a dealership and if you did it would probably cost more than your truck!
The resistance of that sender is 33 ohms (full) to 240 ohms (empty). The resistance of a Toyota sending unit is 3 plus 2 or minus 3 ohms (full) to 110 plus or minus 7.7 ohms (empty). Basically any ohmic readings from 0 to 117.7 ohms (full to empty) on a Toyota sending unit are within spec. In my area there is a outfit that sells new gas tanks and parts as well as used tanks, gauge sender assemblies, etc. that come from southern (non rust climate) vehicles. See if there is a company like this near you. That would be your best bet, I doubt if you would ever find one at a dealership and if you did it would probably cost more than your truck!
Last edited by Hadmatt54; 05-14-2010 at 05:16 AM.
09-22-2010, 06:31 AM
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Im getting ready to replace my sending unit in an 89 1st gen. How difficult is it to drop the tank? Any advice on the procedure? I have looked around and could not find what im looking for.
Could not find anything but the component /parts lay out in the service manual. Did find a bit on removal and instllation in the Chilton Book.
Could not find anything but the component /parts lay out in the service manual. Did find a bit on removal and instllation in the Chilton Book.
09-22-2010, 12:35 PM
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step 1 start with a tank on empty and just un bolt and drop it out...
a second person makes it hand or a floor jakey will work.. place truck on jackstands and disconnect the neg battery terminal.
avoid making sparks and smoking ciggerates while under truck while fumes are venting from disconnect filler neck.
grounding the truck chassi to a good know earth ground will prevent any static electric expolsions that could occur.. not likey but can happen..
a second person makes it hand or a floor jakey will work.. place truck on jackstands and disconnect the neg battery terminal.
avoid making sparks and smoking ciggerates while under truck while fumes are venting from disconnect filler neck.
grounding the truck chassi to a good know earth ground will prevent any static electric expolsions that could occur.. not likey but can happen..
09-22-2010, 12:46 PM
#17
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Im getting ready to replace my sending unit in an 89 1st gen. How difficult is it to drop the tank? Any advice on the procedure? I have looked around and could not find what im looking for.
Could not find anything but the component /parts lay out in the service manual. Did find a bit on removal and instllation in the Chilton Book.
Could not find anything but the component /parts lay out in the service manual. Did find a bit on removal and instllation in the Chilton Book.
I believe this because when I took my bed off, I had major issues with the hardware breaking free from the bed mounts and if I had to put it back on I would have had to weld the bolts back onto the bed to get it back on.
Doing this with the fuel tank hardware is a heck of a lot easier in case of hardware failure. Fortunately for me dropping my tank is now more risky than lifting my flatbed. My level sender is now kaput and searching for one for a while now. $90 at dealership seems kinda steep to me. But if this one lasted this long 175,000 miles and 23 years, it might be worth it. Have not made up my mind to go junkyard hopping for one yet.
