Fuel Pump Module getting hot and melting connector

[D_bone33]

Ok, so i started my car and it sounded really rough and then died. Tried to start it and of course it wouldnt run. I then checked every fuse associated with the fuel pump. Checked everything to see if i wasnt getting either fuel, air, or spark. I then pinpointed it to fuel. So then checked the pump, it had no fuel in the return line on the top of the pump. So then checked the module in the back. The plug had a burn mark somewhat on the left two, which is the fule pump module power and something else. Well i replaced the plug(thanks to a gt500 fuel pump harness i had). So i made a whole new plug. Well then put it back into my old module and the car ran. Then it did the same thing a few more times. I was able to get it running agian and again, and then it died and wouldnt run. Then i had my old gt500 extra module they send you with the pump. I removed the old factory module and put the new gt500 module on there. Well, went to start my car today and it was idleing good and i got in it to leave and it ran out of gas. Popped the trunk and loked at it. It is doing the same thing, plug is burnt up and the connector is pretty shot. I have one more module plug connector i can use, but if i mess this connector up i am out of luck. I just wanted to see if anyone knew anything else to check out. I am figuring it is somewhere on the harness possibly a wire burnt through and it is causeing it to arc or something. The fuel pump in the car is a stock gt pump with a piggy back pump on it. l am maybe thinking that its putting too much strain on the stock harness that was designed to run 1 pump, and now is running two pumps and its bogging down...anybody have any ideas?

 

[19COBRA93]

I'm surprised you're not popping fuses as well. Yes, I would think your piggy back pump has something to do with this. Somewhere in the system there is a major draw that the single FPDM can't handle. You have the GT500 harness, why not use it?

 

[D_bone33]

because the connector on the part that plugs into the gt500 pump is different than the stock fuel pump. So, the gt500 pump harness wont work on the stock pump.

 

[JeremyH]

Did you upgrade the wiring when adding the second pump to handle the increased amp load?

Now, to me sounds like a short, either in a pump itself or the wiring. I'm leaning towards the pump and its likely intermitent since your getting hot enough to burn/melt the pins but not popping fuses.

I wouldnt replace the connector again until you find the root problem, the connector melting is just a symptom. I would pull the hat and inspect it and take some resistance readings.

 

[D_bone33]

Right, I'm in agreeance with you. Would it be possible to upgrade the the harness myself with a bigger gauge wire and and put into the other connector? That's has to be the problem. What is your recommendation to fixing this?

 

[D_bone33]

Ya know, now that I think about it, the power wite on the gt500 pump that's on same location and and the links the other fdpm do it is a lot thicker and a bigger gauge wire...... I could replace the whole left side of the plug with bigger gauge wire

 

[JeremyH]

I doubt this is your problem per say but upgrading the wiring period is a smart idea with adding a pump or putting in a bigger pump thats why I do the wire kit standard with all my fuel systems. At this point the wiring upgrade may just mask the problem. The single stock fpdm can handle 30amps before thermal shutdown and your fuel pump fuse is less than this so Im still 99% sure you have a bad/shorted pump still.

I would pull the hat and inspect it and go from there first.

Yes you can replace the actual wiring itself but a better option is to feed the fpdm via relay directly from the battery if you need help with doing that yourself let me know or I have ready to install kits as well.

http://www.s197forum.com/forum/showthread.php?t=80186

http://www.s197forum.com/forum/showthread.php?t=82470

 

[D_bone33]

OK, I will go pull the damn fuel pump!!!!! Ugh I sure as hell don't want to do that! Haha, so if is a short or something I should see a messes up wire or connector or something of that sort on the pump right? But if the pump is bad, its bad I guess, I'm just hoping it's something I can fix, seeing as its my daily driver I'll besire to check where they spliced in the original wore to control the additional pump

 

[JeremyH]

LOL I hear ya. Before you pull it you can try doing some resistance checks across the power and ground wire form the fpdm to the hat with the car off and at key on as well as check current draw and see if its fluctuating or spiking.

Yes I would look at the splice in for the add a pump and you can do meter checks aross the terminals on the individua pumps. If you need a replacement oem pump I have a bunch laying around as well.

 

[D_bone33]

Damn I don't have a volt matter, but I am pretty sure its one of the pumps doing this, since I have replaced the fpdm and connector and it still is doing the same thing

 

[JeremyH]

Good investment, even a cheap $10-20 mulitmeter from walmart can be very useful for this kind of stuff.
Yeah I'm leaning towards an internaly shorted pump myself. The fuel hat wires themselves are pretty protected, they have emi shielding and are wrapped and then run inside the loom.

 

[D_bone33]

So basically your saying get a new fuel pump? Lol

 

[JeremyH]

Might be a good time to look to upgrade as well lol

 

[D_bone33]

Well, that's actually a down grade! I had a gt500 pump in there and it was broke from factory, so the guys at mustang ranch in auburn gave me that piggy back pump in the mean time, that's why I had extra connectors to play with, I am going to put a gt500 pump in there, just don't have the $$ right now

 

[JeremyH]

I hear ya if you need an oem pump to get the car running for now just let me know.

 

[D_bone33]

Well I am running 13psi on a Saleen supercharger, I don't think I can use a stock gt pump

 

[retfr8flyr]

Jeremy has my pair of GT500 pumps, that are virtually unused. I'll sell them both to you for $75 and you can piggy back them for plenty of fuel.


Earl

 

[D_bone33]

Hey, sounds good, exactly what would I need yo do? I would need a stock OEM pump to biggy back the gt500 off of right? I'm going to call the mustang shop tomorrow and see if they have something laying around the shop that can help me out

 

[D_bone33]

Well, I guess its time to get on the market for a new piggyback pump ready to go for sale or a gt500 pump kit

 

[retfr8flyr]

If you want to do an upgrade just get the Stage 1 setup from Jeremy.


Earl