Help a new mechanic -- fuel pump problems? (1 Viewer)

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Jan 20, 2010
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My 89 FJ62 has been giving me trouble recently and I've decided its time to learn how to work on a car. I'm trying to figure this out without taking my car to the shop but could use some help.

Right now the car cranks but will not turn over.

The battery, starter, spark plugs, distributor cap, and rotor are new. The spark plugs are sparking when I pull them and crank.

I think it is a fuel problem..

I have the engine service manual and when I try to jump +B to FP(i think) to manually test the fuel pump I don't hear a thing. Should it be a pretty obvious sound?

I have looked at the fuses, but have no idea where to look for fuseable links. The main relay is good.

I have also read up on the infamous fuel pressure regulator. Is there any way to test this without shelling out for a new one? Same question with the fuel pump.

I am also pulling up diagnostic code 51...



Recent problems if it helps...

Battery started to die last month is freezing Rochester weather. I cranked it too long and fried the starter.

I installed a new batter and starter but was getting a odd bumping in the engine most noticeable around 1000 rpm.

Replaced the spark plugs and the engine was running like a dream, however it would only start up about 75% of the time. If I gave it a little gas it would usually roar up.

Last week at the bar it wouldn't start back up. I got towed home and haven't had any luck since.


Thanks for any and all help.

Drew
 
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first off, welcome :flipoff2:

yes it is pretty noticable when you do the manual jumper. you should hear the fuel running thru.
if no sound. 2 things, bad fuel pump, not great or bad wiring fairly easy fix.
one way you can check the wiring is to remove the cargo carpet, expose the trap door and run a jumper from the battery or other 12 volt supply directly to the fuel pump wire. if no luck it's the pump, if it works check the wiring in the driver side rear wheelwell, below the jack mount. there is a connector in there and has a tendency to corrode.
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Thanks, that will be my project tomorrow. I'll let you know how it works out.
 
I looks like the pump is fine. If i connect a battery to the pump and then try to start the car, it fires up. Looks like the wiring is bad somewhere.

I'm looking for the connector you showed me. Thanks again.
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Amw2320,
Good diagnosis so far and good explanation of your problem. I believe you have corrosion or wiring problems in your driver’s side rear quarter panel. The wires in question are below the washer reservoir. To get more access you can remove the bottle jack mounting plate. You figured out by connecting the +B and Fp terminals that the fuel pump is not getting power. You then isolated the problem when you directly hotwired it and it turned on. You have some wiring issue in between (just stating the obvious.)

I blew my driver’s side rear tire on the freeway once and the shredded tire actually ripped the fuel pump wire out when it drops down to the tank under the rear quarter panel. If your grommet is corroded under the rear quarter panel then debris gets in there are starts ruining things. Once you fix this, check to make sure the grommet is doing its job to prevent future problems from occurring.

Let us know what you come up with, as you can tell we’ve all dealt with this area of the truck quite a bit. At least your fuel pump works, taking it out is a real pain unless you cut a hole in the cargo area next to the fuel sender cover. :D
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That was definitely the problem. You even called the correct connector. I don't know if I would have been able to tell if the connector was corroded, but I only have melted blob left.
I'll be swapping everything out tomorrow.

Thanks again.
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good catch, it took me awhile to find mine, thus all the pics.
when I did mine, I just soldered the wires together and shrink wrapped them, nice and weather proof. I didn't think I needed that connection anymore.
 
Wow that is a melt down...maybe thats what happened to the wifes 62 years ago we couldn't figure it out so I ran a lead wire from the ignition switch on position.
 
interestingly, this is what happened to my 62 today. for the last few weeks, it's had intermittent starting problems. basically, when it started, it would occasionally sputter and then die. but once it started, it was pretty fine from the on. i changed the fuel filter -- nothing. i cleaned the cold start injector -- nothing. every electrical connection was tested and retested -- nothing. the air intake was swapped out with another 62's -- nothing (although, that did lead to the discovery of a crack in the air intake hose.) our last stop was with the fuel pump -- bingo!

i should say that when i say "we" i mean that i did the fuel filter and CSI, but i let edwin and sean at land cruiser specialists do the serious mechanic's work. kudos to them! they also cut a hole in the floorboard to access to the pump and patched it with some new aluminum in case i ever need to get at it again. yahoo!
 
SHOT CALLER!:clap:

3 Puppies to the rescue again!

there is a reason that Paul knows so much about 'Cruisers!
 
corrosion got the best of your connector

Because corrosion causes high resistance, it started to get hot and melted the connector. make sure the connector is insulated well from the elements and it wont happen again. Silcon injections then wrapping with RF outdoor tape will work.
 
OK guys, it looks like amw2320 got his problem solved so I don't feel so bad about hijacking this thread.

My 62 hasn't run in 4 years. I jumpered the diag. port and no fuel pump sounds or fuel. I pulled up the carpet and the trap door and applied 12v directly to the pump. I heard NOTHING. I used a watt meter inline and saw that when I made the connection it dropped the voltage of my battery to 11v and was pulling 22amps..!!!...:eek:

My question is.....should I be able to hear the pump running if I'm directly over it in the cargo area? I'm going to try again in the morning.

Thanks,
 
It was solved. Thanks again everyone.

HighNear, things I figured out during the repair...
If you open up the trap door, you are looking at the fuel level sender. The pump is back back underneath the floor (you can see it in Randy's picture above) and you would have to cut through the metal bed to access it.'

If you dont have access to the fuel pump, find the yellow connector next to the fuel level sender. That is what runs to it. Connect your battery straight into that connector (Red and green is positive if I remember correctly). That's what got me going.

You will hear it when you connect the battery directly to the pump. It sounds like a big clunk then a small whirl.

Good luck.

If this was all blatantly obvious to you I apologize.
 
Thanks amw,

I found the yellow connector and put 12v to the pump side (just like in your picture above) and heard nothing, but the pump was pulling around 22 amps which sounds way too high to me. I might try to unhook the tank side of the fuel filter and see if there is any flow when I apply voltage.
 

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