• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

87 Ranger STX, 4x4, 2.9 engine's fuel pump relay


greaseyfingers

Well-Known Member
Joined
Nov 4, 2007
Messages
340
Age
53
City
Crookston, Mn.
Vehicle Year
1987
Transmission
Manual
I assume the fuel pump relay is suppose to power both fuel pumps, at the same, time.. Is that correct..

Anyway, I don't think my rear fuel pump is working..

When I took the bowl off the fuel accumulator to change the filter and turned the key on.. I was expecting the rear fuel pump to send gas to the accumulator, when the bowl was still off, and it didn't pump any gas to it, which would have leaked out, being the accumulator's bowl was still off..

Being the the relay is powering the primary fuel pump, I assume the relay is probably working as it should..

Does anyone know which color wire from the relay sends power to the rear fuel pump?? And I will check it with a continuity tester to see if I have power there??

Are there fusible links, from the power source, for both fuel pumps that send power to the the relay and on to the fuel pumps??

Has anyone ever had to replace one of these fusible links, before, without having to replace the fuel pump?? Or, if the fusible link has burned out, then do you think the fuel pump has shorted out, too, causing the fusible link to burn out??
 
I assume the fuel pump relay is suppose to power both fuel pumps, at the same, time.. Is that correct..

Anyway, I don't think my rear fuel pump is working..

When I took the bowl off the fuel accumulator to change the filter and turned the key on.. I was expecting the rear fuel pump to send gas to the accumulator, when the bowl was still off, and it didn't pump any gas to it, which would have leaked out, being the accumulator's bowl was still off..

Being the the relay is powering the primary fuel pump, I assume the relay is probably working as it should..

Does anyone know which color wire from the relay sends power to the rear fuel pump?? And I will check it with a continuity tester to see if I have power there??

Are there fusible links, from the power source, for both fuel pumps that send power to the the relay and on to the fuel pumps??

Has anyone ever had to replace one of these fusible links, before, without having to replace the fuel pump?? Or, if the fusible link has burned out, then do you think the fuel pump has shorted out, too, causing the fusible link to burn out??

there is fusible link...but it is before the relay from the power source.

do you have twin tanks or single tank??

either way,(from the book), it shows a Pink/black & a yellow coming out of the interia switch to the high pressure pump.

on the single tank... there looks like a resistor (1.00 +&- .05 ohm) feeding power to the in tank pump, also Pink/black wire

and a black after the both pumps going to the ground...some where

hope that helps
 
1 relay, 1 wire, feed the 2 pumps on my '88.

There was a single connector on the drivers side that you could use to test with. Note the color of the wire going to the cab mounted pump, and you'll see it near the dash plugs. You can apply 12 volts here to run the pumps, but at the same time you don't want to run them with no fuel either. But could be a good spot for testing the circuit. It's a breaking point after the inertia switch and right before it goes to the pumps.

Pete
 
are you having problems getting fuel I know the in tank pump is just supposed to push the fuel up the tube to feed the high pressure punp if it is not working you will burn up the second pump the more fuel in the tank the less the pump in the tank has to work if it is working dont fix it. My schematic says one fusible link so if the pump in the tank is not working it is either the wiring or the pump either way you will probably have to pull the tank as it uses the same power as the other pump and if it is working maybe you can find the ground for both coming off the loop and clean/sand them
 
are you having problems getting fuel I know the in tank pump is just supposed to push the fuel up the tube to feed the high pressure punp if it is not working you will burn up the second pump the more fuel in the tank the less the pump in the tank has to work if it is working dont fix it. My schematic says one fusible link so if the pump in the tank is not working it is either the wiring or the pump either way you will probably have to pull the tank as it uses the same power as the other pump and if it is working maybe you can find the ground for both coming off the loop and clean/sand them

When I took the bowl off the fuel accumulator to change the filter and turned the key on..

I was expecting the rear fuel pump to send gas to the accumulator, when the bowl was still off..

It didn't pump any gas to it, which I think should have leaked out, being the accumulator's bowl was still off..

Doesn't the rear fuel pump gas to the accumulator's bowl, first, before the primary fuel pump sends it to the fuel rail??

If the rear fuel pump isn't working?? Does the primary pump have enough suction to pull the fuel from the tank, without the assistance of the fuel tank's pump??

My Ranger runs, but doesn't seem to run like it should?? When the codes were last checked at a auto parts store.. They said the code was saying that it was running lean..

If the rear fuel pump isn't working, from your first hand experience, how did your Ranger run and perform, until you got it fixed??
 
your rear pump was proberly doing like my pump just did, was only working half way or something, just enough to get the fuel there and then the second pump was doiing all the hard work.

yes the low pressure pump should be pushing the fuel up to the accumulators bowl and to the high pressure pump, the high pressure pump can't pull fuel, only push it.

I would take a jumper from the + battery and unhook the high presssure pump, then jump the low pressure to see if it pumps, this way you dont take a chance of burning up your high pressure pump.

Robert
 
there is fusible link...but it is before the relay from the power source.

do you have twin tanks or single tank??

either way,(from the book), it shows a Pink/black & a yellow coming out of the interia switch to the high pressure pump.

on the single tank... there looks like a resistor (1.00 +&- .05 ohm) feeding power to the in tank pump, also Pink/black wire

and a black after the both pumps going to the ground...some where

hope that helps

You mentioned, "on the single tank... there looks like a resistor (1.00 +&- .05 ohm) feeding power to the in tank pump, also Pink/black wire"

"and a black after the both pumps going to the ground...some where"

Does anyone know where this resistor is located and where the fuel tank's pump ground is, on my Ranger's single fuel tank??

I'd like to see if I have electrical current to this resistor and going through it..

Then if I have electrical current, to that point.. I'd like to clean the rear fuel pump's ground, if I'm able to find it without taking the tank off, or the pickup's bed..
 

Sponsored Ad


Sponsored Ad

TRS Events

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Ranger Adventure Video

TRS Merchandise

Follow TRS On Instagram

TRS Sponsors


Sponsored Ad


Sponsored Ad


Amazon Deals

Sponsored Ad

Back
Top