Well my Cobra is finally out with procharger and I've got a bug. Right after 6k the fuel pressure drops off to 18psi from a higher 50. My fuel system consists of a Ford GT pump with a KB boost a pump, the bigger one available. Any ideas? The car's been wideband tuned and has been datalogged but still having som trouble figuring it out.
Please Help with bug in my Cobra
- Thread starter GHRVENOM
- Start date
i was having a similar problem when cruising....fuel pressure would drop from 30-40 to about 15 then back up to like 30-35. from what i have heard from peoples comments is that it needs to be tuned out. something to do with the car shutting off the fuel injectors to save fuel or something. then again, our problems could be different. just a suggestion though.
Thanks for your input man. The tune's been worked on but the pressure still goes down after 6k. Hopefully I can figure it out soon.
so what did you datalog?
did you log voltage at the pumps? How about duty cycle of the pump?
do you have a modified fpdm?
Is your bap turned all the way up? How is it wired (post or pre fpdm)?
did you log voltage at the pumps? How about duty cycle of the pump?
do you have a modified fpdm?
Is your bap turned all the way up? How is it wired (post or pre fpdm)?
Datalog shows drop of voltage after 6k. What's a modified fpdm? Do I need one and if so where can I get one. Tried turning the bap to different settings and nothing. BAP is wired in the back of the car to an powersource in the rear as per the manual.
hmm, drop in voltage is causing the drop in pressure.
whats it drop to? If lower than say 13 volts, you may have issues.
There could be a few reasons for this:
1. The alternator is sucking wind up top.
2. The fpdm is going into thermal limiting (it gets modified to prevent this, and to reduce draw)
3. the bap wiring might not be helping.
You can wire the bap in either pre fpdm or post fpdm. Which did you do?
whats it drop to? If lower than say 13 volts, you may have issues.
There could be a few reasons for this:
1. The alternator is sucking wind up top.
2. The fpdm is going into thermal limiting (it gets modified to prevent this, and to reduce draw)
3. the bap wiring might not be helping.
You can wire the bap in either pre fpdm or post fpdm. Which did you do?
BAP is post fpdm.
you'll want to change that regardless.
Will do, I'll start there thanks.
My bad, it's actually pre fpdm with switch.
ok. so what kind of voltage are you seeing at the pump?
Ok took off the switch and they wired it direct and that fixed the voltage problem, thanks guys. One problem left, I ran her and my tech did a data log and found fuel pressure is droping at peak rpm and thinks the basket is getting sucked dry. My car had right at quarter of gas on that run. Is there a fix for this?
...and today the car threw code P0190 which is fuel rail pressure sensor circuit malfunction. Could that be causing my problems?
Do you have an 03-04 cobra tank?
No I have the stock 99 tank.
SVTHII
Banned
drill out the pump casing... just make sure you have a new fuel filter.
Well got fed up with this dilema and ordered an 03 Cobra tank with pumps today. How much hp can those pumps support. I have a backup boost a pump if I need to install as well. Do I need to modify my fpdm with this setup?
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