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FPDM Replacement Cured My Hesitation
- Thread starter UFGatorGuy20
- Start date
I'm trying to decipher all you questions... hope this helps...
If you replace your FPDM, FRPS, install a K/B Disk to prevent the FRPS from failing, or any combination of those parts, I do not believe you will need a retune. That's just based on my knowledge though. You aren't changing anything that would adjust your air intake rate or your fuel input rate (although replacing a bad part would just make the part operate as it should). Neither part is a power adder or reducer.
For what it's worth, I'm replacing my FRPS early this week, then getting it tuned May 4th. I'm not getting it tuned because I'm replacing those parts though. My local tuner is incredible. He'll pull every ounce of power out of the car. I haven't had it tuned since I bought it. Always great to have additional piece of mind.
toulsey is the best place to buy the frps.
Thanks... I'm calling Tousley tomorrow for sure. :beer:
Got it ordered from Tousley for $74.92 (including shipping). :beer:
Glad you got your problem fixed and your write-up will undoubtedly help others down the road who suffer similar symptoms. You got to feel really good now taking your car out and knowing it is going to run like it should. :thumbsup:
Glad you got it cheaper. Tousley FTW
I have a similar issue now. I blew my FRPS a few weeks back, and I guess it caused a pressure spike and one of my fuel lines on top of one of the pumps popped off (I have a PPRV delete). I got the fuel line back on and torqued the crap out of the hose clamp, and finally decided it was a blown FRPS which was causing the stalling. The diaphragm didn't blow on the FPRS, just the electronics, as there was no fuel smell in the vacuum line. Fast forward a few weeks to now, and now I have this very prominent hesitation at WOT under heavy load (WOT is fine in 1st and 2nd, as the tires have a very low friction coefficient out here in the desert with our sandy roads). Spark blowout was suggested to me, but I don't see that occurring out of the clear blue (I was out for blood on my way to Vegas a week or two ago, when the car was running well, going WOT frequently). I think the pressure spike(s?) caused by the bad FPRS may have damaged the FPDM and it's having trouble getting the required amperage to the pumps at high load. Does this sound like a reasonable explanation/diagnosis?
This is a tough thread to follow. I think the OP had a hesitation/stall issue and that he cured the hesitation with a new FPDM leaving him with just the stall issue. Somehow it morphed into an FRPS discussion when the guy has a deceleration/stall issue (??).
The Stall Issue for the Terminator remains unsolved. The AMZ2 ECU flash has not cured it in my car. One fellow posted some time back that his tuner cured the problem 'with lots of gas at idle' but never clarified. FWIW this is even after FPDM change/ KB FRPS change/ IAC change/ TPS adjust/ AMZ2 reflash/ dashpot adjust/even installing a clone tune from an identically modded Cobra from the same reputable tuner operating in the same atmosphere.
Both cars: Whipple/single blade/BAP/60s/CAI etc etc
Many threads have died out (so to speak) with the posters resignedly living with The Stall on a twin screw Cobra.
I am surprised that slowing the idle decel with the dashpot didn't cure The Stall. I suspect that the issure is with plotting the fuel schedule as the engine decelerates.
Anybody had a specific luck with the remaining problem-The Stall on a twin screw?
The Stall Issue for the Terminator remains unsolved. The AMZ2 ECU flash has not cured it in my car. One fellow posted some time back that his tuner cured the problem 'with lots of gas at idle' but never clarified. FWIW this is even after FPDM change/ KB FRPS change/ IAC change/ TPS adjust/ AMZ2 reflash/ dashpot adjust/even installing a clone tune from an identically modded Cobra from the same reputable tuner operating in the same atmosphere.
Both cars: Whipple/single blade/BAP/60s/CAI etc etc
Many threads have died out (so to speak) with the posters resignedly living with The Stall on a twin screw Cobra.
I am surprised that slowing the idle decel with the dashpot didn't cure The Stall. I suspect that the issure is with plotting the fuel schedule as the engine decelerates.
Anybody had a specific luck with the remaining problem-The Stall on a twin screw?
Add me to the hesitation/stall list.
Maybe we can get a sticky since so many people have this issue.
We at least need to keep the thread or a thread open for those who have it.
I talked to a former team mustang Calibrator about this and he said "What you are most likely experiencing is a typical WOT dyno tune vs. an OEM part throttle driveability calibration. The WOT cal is pretty easy, but many places can hack the open loop WOT cal to make dyno numbers but it is the little system interactions that have a large effect on drive-ability and robustness".
So far:
I have replaced plugs 3 times,cleaned maf and sensors, clean IAC, replaced FRPS,replaced COPs,cleaned Air filter in my CAI (maybe the JLT CAI is the culprit?) tried a different tune (my custom one from Anderson Ford and the Diablo performance) still have hesitation/studder like a bad plug under 2K after its fine. and no prob under boost.
I wonder if Stock Owners have this issue. I am half tempted to take it back to stock and have Ford look at it under warranty.
Subn...
Maybe we can get a sticky since so many people have this issue.
We at least need to keep the thread or a thread open for those who have it.
I talked to a former team mustang Calibrator about this and he said "What you are most likely experiencing is a typical WOT dyno tune vs. an OEM part throttle driveability calibration. The WOT cal is pretty easy, but many places can hack the open loop WOT cal to make dyno numbers but it is the little system interactions that have a large effect on drive-ability and robustness".
So far:
I have replaced plugs 3 times,cleaned maf and sensors, clean IAC, replaced FRPS,replaced COPs,cleaned Air filter in my CAI (maybe the JLT CAI is the culprit?) tried a different tune (my custom one from Anderson Ford and the Diablo performance) still have hesitation/studder like a bad plug under 2K after its fine. and no prob under boost.
I wonder if Stock Owners have this issue. I am half tempted to take it back to stock and have Ford look at it under warranty.
Subn...
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