First Generation Ex - Fuel Pump not pumping

[Dignan]

Well, this is what happened. I live in Texas, my Explorer and motorcycle were in Utah, so I decided to tow them to Texas when I visited Utah. I changed the fluids and charged the battery since it had been sitting for a while. It fired right up once the battery had some juice. I left it running and loaded the motorcycle on the trailer first. Then went back to drive the explorer up to the trailer. Walked over to it and it was dead. Cranks great but no fuel. Can't hear the whine of the pump when turning the key. I have been searching for 3 days and can't find exactly what I need. I have checked the inertia switch and it is in the proper position. I next went to the Power distribution block to check fuse and relay. Fuse is good. Relay is difficult to get to so tomorrow I will probably unbolt the power distribution block to get to the relays underneath, but what I found was the VIP connector dangling and another single wire in the same tape bundle that was also dangling and also stripped. Should these be plugged in somewhere under normal circumstances? If that doesn't make much sense, maybe someone could post a picture of a normal relay setup for a 91.

 

[MrShorty]

but what I found was the VIP connector dangling and another single wire in the same tape bundle that was also dangling and also stripped.

That sounds like the self-test connector and the self-test input (STI) connector, both of which are there for the self-tests, and shouldn't effect the fuel pump.

There's a fuel pump test lead in the VIP connector (short side of the trapezoid if memory serves) that you can ground to close the fuel pump relay.

At this point, my recommendation is to get a wiring diagram (even the one in Chiltons is adequate, and can be found on the internet in the vehicle repair guides at autozone.com) and a voltmeter. The fuel pump circuit is fairly straightforward. Find out if there's a break in the circuit on the positive side of the pump.

 

[Dignan]

Ok, sounds like good advice. I'll do that tonight or tomorrow. I figured the leads didn't need to be connected (thanks for confirming that), but is there any problem with the single wire being stripped? can it short something?

Also, if I ground the short side of the trapezoid, does that make the fuel pump instantly turn on, or does it still just come on with the key?

 

[Dignan]

So, I tried a little bit of troubleshooting. BK/Y wire going into relay is hot, DG/Y at Inertia Switch is not hot with KOEO. Assumed that meant bad relay. New relay did not solve problem. What does KOEO do to the voltage at the relay wires?

 

[MrShorty]

When you first turn the key on (without starting the engine), the computer closes the fuel pump relay for a few seconds to pressurize the fuel system, then opens the relay to shut the fuel pump off. No voltage at the inertia switch is normal, unless you are looking at it during those first couple of seconds after turning the key on.

Also, if I ground the short side of the trapezoid, does that make the fuel pump instantly turn on, or does it still just come on with the key?

Key still needs to be on for the fuel pump to run.

 

[Dignan]

Sorry, no updates. My meter died, so I haven't been able to do any further testing. I'll update when I get a new meter.

 

[Dignan]

Update: I cut a trap door above the fuel pump last night. Most of the previous testing was pointing toward a bad pump so I went ahead and ordered one but I also got a new battery for my multimeter so today after work I'll test the leads right at the pump just to make sure. I guess I was in denial because the pump isn't very old, but at least I learned a lot and since I will change it myself this time it will be cheaper.

 

[Dignan]

with the trap door cut right above the pump and a working multimeter, I was able to test the power right there. I get 13v for a few seconds and then it drops to 6v right at the cover for the pump. I don't here any noise from the pump. I am bugged that the pump died so soon after being put in, but it looks like that is definitely the cause of my trouble. I am now trying to pull the fuel lines to take out the pump and lets just say its a good thing there aren't any kids around to hear me. I tried cutting up the cap of a sharpie to no avail and went and purchased a set of disconnect tools and nothin. I can't get those lines to budge a millimeter. I have never actually pulled a fuel line, but I imagine it isn't rocket science. I am supposed to stick the tool around the line and push it into the fitting, right? Am I missing something here? How can I get these lines off?

 

[Turdle]

I went through this, lost my cool, dropped a few F bombs which turned neighbors heads and ended up mangling the crap out of the internal spring clip thing.
What i found though-if I used the next size up tool from what looks like "should" work it actually worked better. Use a pair of good pliers to grip the fuel line, shove the quick disconnect tool in ,pull tool out, rotate about 1/8 turn and re install tool, listening for little plinking sounds. There are 5 fingers to release inside. Work the fuel line back and forth-keeping the tool inserted and the line will come off.

 

[Turdle]

Here is a picture of what the springs look like inside the fuel line. The long thin fingers hold the sring in the metal connector sleeve, the shorter fingers wedge in behind the nipple on the fuel pump line. pushing them outward will release them, if they are pushed out all at once. This is why I recommend rotating the tool a few times to be sure you are releasing all of them

I bought a cheap kit of dorman clips off ebay.

 

[MrShorty]

It seems to me that the quality and design of the tool can make a huge difference. About a month ago, I changed my fuel pump, and wrestled with those connections for about an hour before I decided to try something else. Went to Carquest and found a little bit more expensive set of fuel line removal tools with an angled grip. Fuel lines came off on the first try with this set of tools. Part of me hates to suggest going out and buying a different set of tools, but it might be worth the expense if you can find a set that will disconnect those quickly and easily.

 

[Dignan]

I tried the next size up and it wont even fit in the fitting. I tried the next size down and it acts like the first size I tried. I worked it all around, pushed the fuel line in all different directions, sprayed the crap out of it with WD40, pushed the tool in every direction until I couldn't move my fingers anymore (it hurts to type this message). I have heard no plinking sounds and have made absolutely no progress over the last 3 hours. I decided to work on the filler neck (it has some rust I need to clean up), and went to grab my little metric socket set and the 7mm is missing so I can't do that either. I guess this isn't my day, but it is the only day I have off for the next while, so it kinda has to be the day I fix the fuel pump.

 

[Turdle]

It seems to me that the quality and design of the tool can make a huge difference. About a month ago, I changed my fuel pump, and wrestled with those connections for about an hour before I decided to try something else. Went to Carquest and found a little bit more expensive set of fuel line removal tools with an angled grip. Fuel lines came off on the first try with this set of tools. Part of me hates to suggest going out and buying a different set of tools, but it might be worth the expense if you can find a set that will disconnect those quickly and easily.

I went out and got a couple more also, however ended up grinding on one in frustration without success. Please post the tool you have.

 

[Dignan]

I went to autozone and picked up this set:

http://www.amazon.com/OEM-25052-Conditioning-Fuel-Disconnect/dp/B000CMHKI6

It is definitely on the cheap side, and I think I will have to try something better.

 

[Turdle]

The one which finally "worked" for me was the second one up in a set like this

Don't bother with one of these-

 

[Dignan]

I was thinking about trying this set:

http://www.harborfreight.com/4-piece-fuel-and-auto-trans-line-disconnect-tool-set-96834.html

Harbor Freight isn't what comes to mind when I think of "higher quality", but you never know. It is at least aluminum, so maybe it will hold up better than the plastic. I guess I'll run over there and see what they have since I need a 7mm socket anyway.

 

[Ayegor]

I bought KD tools 3290 fuel line tool. I believe I got it at NAPA, but they are available at most auto supply stores. Here's a link to one on eBay. It works for me every time, no hassle. http://cgi.ebay.com/ebaymotors/KD-T...dZViewItemQQcategoryZ43993QQitemZ190509590277

 

[Dignan]

I haven't heard a lot of good things about those center swivel types, but at this point I'll try any of them. I went to harbor freight and they are out of the disconnect tools and due to a shipping error, they wont get any for 6 weeks. So I guess the stars aren't going to align for me to replace the pump today. And to think, I started at 215 thinking I could go pick up my wife from her job (close enough that she walks) at 245. Here we are at 845, and I still can't get the hoses off. I did however pick up a 7mm socket while at harbor freight so I was able to remove the filler neck. I think that might actually be what killed my fuel pump. I don't know if the mechanic that put the last pump on gave me a new strainer. I would think it would be obvious, but I think he was pissed at me. (Long Story) So he might not have cared. Anyway, there was more rust on it then I could see from the outside. There was a rust bubble about the size of a silver dollar underneath the rubber hose. When I chipped that off, it revealed a hole about the size of a pencil eraser in the filler tube. So rust was getting into the gas. If that strainer didn't catch it and the pump sucked it up, that very well could explain the premature failure of a not-very-old pump. I hadn't planned on draining the tank since I'm not dropping it, but I may have to drain it and clean the tank. I was hoping to sandblast the rust and reuse my filler neck, but I guess I'll have to get a new one, or at least one from the junk yard that is less rusty.

 

[MrShorty]

Please post the tool you have.

Carquest doesn't have much on their web site, but the set I bought is similar to this set from Snap-on http://buy1.snapon.com/catalog/item...&group_ID=1439&store=snapon-store&dir=catalog or this set from Lisle http://www.toolsource.com/angled-disconnect-tool-p-97029.html I don't remember what I paid, but it seems it was around $18.

 

[Dignan]

I should have stopped in Spanish Fork when I towed it through...