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maxwell6
07-26-2021, 08:12 AM
Wondering if someone can shed some light on a issue I had yesterday. Was out for a drive, did about hour and a half of normal 80 to 50 zones. Then was cruising at 30km along lake drive in Sutton Engine temp was about 196* then started to lose fuel pressure then stall and no pressure at all. My car is 4.6l 2v vortech supercharged, return fuel system. the fuel system is plumed 03 cobra tank,triple pump fuel hat running two pumps only. 2 AEM 340s wired to run all the time. -8 supply to y-block feeding the rear of the division x fuel rails, out of the front of the fuel rails to aeromotive reg then return fron reg to tank. Also all upgraded wiring. Does this sound like a fuel overheating issue/vapor lock. Any input would be appreciated. Thanks Mark. BTW after getting CAA to tow me home the fuel pressure returned and was able to start with normal looking pressure.

bbriann
07-26-2021, 11:46 AM
If this is a "new" setup this season it is a good chance it is vapor lock. I have external dual pump and really gey loud and whine after a half hour of running. The fuel temp seams ok with little change and amperage draws stays same they just get loud. They are dual 320 pump size. Your in tank pumps will be putting heat into fuel. I insulated my fuel rails and added larger 12 an line to pump suction in hope pumps run cooler.

ZR
07-26-2021, 12:04 PM
When it quit, could you hear the pumps running?
Is the tank properly vented?

maxwell6
07-26-2021, 12:16 PM
I have been running this set up for a while. The only change is the AEM pumps about 1 month ago. Directly after I lost fuel pressure I did not hear the pumps. When they cooled down a bit I could hear them again. Last night they seemed fine pressure was good.

Laffs
07-26-2021, 01:33 PM
What gauge wiring did you hot wire the pumps with? What's the relay system and is it capable of supporting the 30a draw from both pumps?

ZR
07-26-2021, 03:27 PM
-singe or dual relays?

maxwell6
07-26-2021, 07:51 PM
My wiring set up is Dual 10 gauge feed from battery, Dual 40 amp relays fused, 12 gauge power and ground wires. Its a Lethal performance dual fuel pump wiring kit.

ZR
07-26-2021, 08:15 PM
If both pumps quit at the same time, has to be either trigger wire to the relays or main power / feed wire issue.

maxwell6
07-26-2021, 08:27 PM
Thanks for the input I will go through everything and make sure its all good.

ZR
07-26-2021, 08:34 PM
Assume your triggering via the FPDM module trigger wire?

maxwell6
08-03-2021, 05:34 PM
Update to fuel pump issue. Dropped the tank pulled the hat found, 1 short hose from pump to hat blown,other was not split but very soft. Was not able to get more than 10 psi pressure. Also when I installed these pumps, i purchased "submersible fuel hose from jobber". What I removed was not submersible did not hold up to the fuel 91 octane only. will not make that mistake again. Thanks for all the help provided here. BTW replacing the pumps as well.:mechanic:

ZR
08-03-2021, 06:20 PM
FYI, submersible spec hose has spec printed on the hose itself, also has date of mfg on it to be sure your not getting hooped on 10yrs old. Only became aware after a recent issue we had after installing newly purchased hose that was over 10yrs old n failed shortly after install.

Laffs
08-03-2021, 09:56 PM
I blew apart 5 pieces of "submersible" hose from various parts stores, retailers. The only thing that lasted long term for me is the corrugated stuff made by ATL and sold on Summit Racing.