Fore hat and dual FPDM install help!!!

[Dawgstang]

I have everything connected, but left the Fore fuel out of the tank so I could check and make sure the level sender and the pumps work prior to installing the tank. I turned the key to on position without starting car and nothing works. I mean the pumps did not make any noise and the fuel gauge just sits on empty when I move the fuel sender arm. I have the fuel level sender connected to the stock wiring and the GT pumps connected to the new dual FPDM harness from Lethal. Is there any way to check this stuff before installing the fuel tank?

 

[sean r]

Im not a expert at wiring but did you try grounding it.

 

[Mystic03]

lethals fpdm i think is plug n play..have any instructions...pics of install?

 

[JRS03]

Any updates ?

 

[Dawgstang]

Lethal's harness is so easy to install. Almost impossible to screw that up. Double checked it, looks OK. With the key in the on position, should the pumps be running continuously? I have the fuel tank completely removed including all vacuum lines.

 

[Dawgstang]

Double checked Lethal's harness. Almost impossible to install wrong. Key in run position, what should the pumps be doing? Should they be trying to build pressure. I have fuel tank completely removed, fuel lines and vacuum lines disconnected. I only have Fore fuel hat connected to stock harness for fuel level sender and GT pumps connected to Lethal's harness.

 

[Mystic03]

Double checked Lethal's harness. Almost impossible to install wrong. Key in run position, what should the pumps be doing? Should they be trying to build pressure. I have fuel tank completely removed, fuel lines and vacuum lines disconnected. I only have Fore fuel hat connected to stock harness for fuel level sender and GT pumps connected to Lethal's harness.

are you checking for voltage at the hat?

 

[black03]

Double checked Lethal's harness. Almost impossible to install wrong. Key in run position, what should the pumps be doing? Should they be trying to build pressure. I have fuel tank completely removed, fuel lines and vacuum lines disconnected. I only have Fore fuel hat connected to stock harness for fuel level sender and GT pumps connected to Lethal's harness.

The stock returnless fuel system even with the dual harness installed will not keep the pumps running full time until the car is started. When you put the key to the on position they will however prime for a second and then shut off.

Hope that helps.

Jared

 

[Dawgstang]

No I have not tried checking the voltage, but now I will. I knew the pumps would prime the fuel system for start, but with fuel line disconnected at tank, I thought the would run continuously.

 

[Mystic03]

No I have not tried checking the voltage, but now I will. I knew the pumps would prime the fuel system for start, but with fuel line disconnected at tank, I thought the would run continuously.

no only when car is running will the pumps run constantly, you got testies priming em dry though

 

[Dawgstang]

Ok this time I had my son put the key to the on position while I held the fuel hat in my hands, and they did turn on for a few seconds. Now my other problem. Why isn't the fuel level sender working? I must of broke it, removing the stock fuel hat. You just connect the sender to the stock wiring right? Oh we'll I guess I'll order a new one from rock auto for $85 bucks.

 

[TRBO VNM]

No I have not tried checking the voltage, but now I will. I knew the pumps would prime the fuel system for start, but with fuel line disconnected at tank, I thought the would run continuously.

Why would you think they would run continuously if the fuel line was disconnected? The line doesn't control the pumps.

If you hooked them straight to the battery they would run all the time.

The fuel level, there is a delay. You can't move it and then go look to see if the gauge moved. Last time someone tried that it took almost 5min to see the change on the gauge.

Have you checked your fuel pump fuse? How about the inertia switch?

 

[Dawgstang]

Thanks TRBO VNM I took your advice and moved the fuel level arm and sure enough 5 minutes later, the gauge started to move. You saved me $85 for a new one.

 

[TRBO VNM]

Thanks TRBO VNM I took your advice and moved the fuel level arm and sure enough 5 minutes later, the gauge started to move. You saved me $85 for a new one.

No problem. :beer:

 

[Black*Death]

Thanks TRBO VNM I took your advice and moved the fuel level arm and sure enough 5 minutes later, the gauge started to move. You saved me $85 for a new one.

I would just reinstall everything and try it. besides the fuel filter and the filler neck gasket, dropping the tank is easy.

Putting it back is a bit harder by yourself but can be done. i think you are simply frustrating yourself by trying to check everything while tank is on the ground.

I understand your pain as I have dropped my tank 4 or 5 times now...can drop it in 11 minutes...but like always, learned a lot about my fuel system

 

[JRS03]

Did u have a BAP installed prior to this install ? The reason I ask is because I just had the same problem... pumps were not getting power, come to find out, the green wire with white stripe that the BAP slices into wasn't connected after removed the BAP.
Wired the green wire back and walla.... my FPDMs have power and pumps kick on.

 

[cj428mach]

to the battery they would run all the time.

The fuel level, there is a delay. You can't move it and then go look to see if the gauge moved. Last time someone tried that it took almost 5min to see the change on the gauge.

This is normal/common? I bought my Cobra about 4 months ago and I just assumed the sender was screwed up or binding. The last time I drove it I fueled it up at around a quarter of a tank and I bet it took about 5+ mins for it to finally get up to full. It seemed like it would jump up about a 1/4 a tank then sit for a minute or two. Then jump another quarter of a tank then sit.

 

[TRBO VNM]

yes it is normal because of the design of the sending unit

 

[cj428mach]

yes it is normal because of the design of the sending unit

Thanks man thats good info. I thought about dropping the tank just to investigate. So I'm glad to hear thats normal.