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Ford Explorer Community - Maintenance - Modifications - Performance Upgrades - Problem Solving - Off-Road - Street
Explorer Forum Covers the Explorer ST, Explorer Sport, Explorer Sport Trac, Lincoln Aviator, Mercury Mountaineer, Mazda Navajo, Ford Ranger, Mazda Pickups, and the Ford Aerostar
Do you think you might need a voltage driver for the pump? Just for conversation sake, could the PCM output volatge be too low for what you need to maintain pressure?
Just to be safe and so i know..how would i double check this?? Im going to have the tank out to replace the pump so now would be time to just double check EVERYTHING. .
Just to be safe and so i know..how would i double check this?? Im going to have the tank out to replace the pump so now would be time to just double check EVERYTHING. .
If you think you have the flow part of the equation sorted, and if the voltage from the PCM is pegged and fuel starvation still occurs.
I think some guys go to a 16v system to overdrive the fuel pump.
If you think you have the flow part of the equation sorted, and if the voltage from the PCM is pegged and fuel starvation still occurs.
I think some guys go to a 16v system to overdrive the fuel pump.
How exactly does the ecm control the pump on a obd1 system? ? Is it variable? I kindof was under the impression the pump just ran full open all the time (whatever voltage im producing) and the regulator just adjusted pressure. ..
Well more issues now..got a exhaust manifold leak..the gaskets has become brittle and blown out in some places..knew i should've stuck with the metal gaskets. ..its going to be a PIA to change them out and i also have stage 8 locking bolts on them..
The fuel pumps do run on full voltage for pre-99 Fords. The bigger pumps though take more current, which can push the limits of the stock wiring, depending on how big the pump is. Stock is what, 80lt/hr volume, so 255-340 is a good bit bigger. I haven't read enough about cars with over 255lt/hr pumps, which do okay with stock wiring.
I'd check the voltage at the rear pump wiring, while the truck is running. That might tell you enough to say that it's okay, or needs more wiring.
BTW, for a filter, here's the best deal I found for an external unit that should cover my needs. I didn't check about E85 compatibility, or if it's good for serious high HP racing. But it's a nice large aluminum unit with a large filter, available with different fine screens.
(dead link)
Well i went with a fuelab 51502 regulator, summit 230123 filter and TRE 340-HF..also got my fan for the IC and header gaskets. ..going to try and tackle it all this weekend
Well the fuel pressure definitely rises when you gas it(vacuum drops) but cant tell obviously what its doing when WOT and boost kicks in but as far as the wideband is reading its doing the same thing it was doing on the dyno..
You go WOT and gauge jumps to like 10.5-11 for like 2 seconds then slowly crawls up leaner and leaner..i did 2 pulls tonight and had to let off around 10psi because it was getting up to about 15..obviously its not tuned but something is causing it to go lean and seriously doubt it fuel pressure or flow now...personally i think he has the open loop programed wrong..every time it goes into open loop it seems to go lean...
If your fuel pressure doesn't rise with boost then it will run lean.
Boost and fuel pressure are both measured in psi, so for every 1 psi of boost the fuel pressure should rise 1 psi.
Make sure you have the regulator hooked up to a vacuum/boost hose.
Vehicles always start in open loop, that means it is ignoring the O2 sensors and running off the base fuel tables with no correction.
When they go into closed loop the PCM corrects for things based off the O2 sensor readings.
What did you mean by you can not tell what fuel pressure is doing at WOT? Is the gauge under the hood?
If your fuel pressure doesn't rise with boost then it will run lean.
Boost and fuel pressure are both measured in psi, so for every 1 psi of boost the fuel pressure should rise 1 psi.
Make sure you have the regulator hooked up to a vacuum/boost hose.
Vehicles always start in open loop, that means it is ignoring the O2 sensors and running off the base fuel tables with no correction.
When they go into closed loop the PCM corrects for things based off the O2 sensor readings.
What did you mean by you can not tell what fuel pressure is doing at WOT? Is the gauge under the hood?
Played with it today and right about 70% throttle is when it goes lean..i cant really tell on cold starts because i think it takes a couple seconds for my wideband to start reading right then i can hear it switch from open to closed..it goes lean for about 20 seconds then starts jumping from about 14-15ish..i just think it needs the tune adjusted now,the pressure seems to be good..i will say when he adjusted it last time on dyno for My ethanol change,i had about e75 in it and now i have e83 so that might be why its off also..previous tune was for e50,i still had about 6 gallons of e50 in the tank when i topped it off with e83ish so it gave me around e75
The tensioner idler is actually the same between the early ohv to the v8. We found this out this morning searching though all my spare junk. I think his issue was it was an aftermarket pulley with a very tight belt and it was the weakest point. I bet belt tightness has contributed to making the water pump angry also.
