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Having issues with my 93 L MT again. Turns out the last time the fuel pump o ring has worked its way out of the sending unit, bam barely enough pressure to start. Installed properly, and all is well!
I thought. Drove the car another 500 miles and now I'm having another issue. Initially I noticed a lack of power. Strange. Slowly getting worse. Hmm. Yesterday I did the Rio swap and it was pretty bad on the test drive. It was COLD last night. Tested ECT and it's fine. Unplugged o2 sensor today and drove the car. Problem steadily got worse.
At idle, the car smelled RICH before unplugging o2. I have no catalytic converter so the difference was quite noticeable. However, it doesn't smell rich at idle after plugging o2. Guessing the pcm reverted to a base map of sorts without the o2.
So my theory here is: Fuel starvation causing a leaner condition at part throttle. PCM adjusts but no fuel starvation at idle, thus a rich idle. Tested fuel pressure, 28psi with the car running and regulator hooked to intake manifold. However, revving the car didn't budge the fuel pressure an inch AND with the vac line unhooked, I got the same 28psi steady as a rock. AutoZone tried telling me 68psi was what I was looking for. Uhh then why did that GP Sorensen Regulator I had you look up say 38psi? Mine is weak but still.
So should I be ordering a FPR from RockAuto or what? I'm pretty positive it isn't ignition. I just went through and took care of EVERYTHING aside from the distributor itself and I did check timing this time. It's not a misfire, at WOT it simply won't go anywhere. It's like it is getting fuel, just not enough. And I know the amount of fuel delivery that 10psi changes is pretty significant. RC says a 120cc injector is actually a 100cc with that pressure change. I can see that causing an issue potentially. Sorry for the essay guys, I'm just at a loss here and my Mustang kills me on gas for work. Thanks in advance for any help or suggestions.
I thought. Drove the car another 500 miles and now I'm having another issue. Initially I noticed a lack of power. Strange. Slowly getting worse. Hmm. Yesterday I did the Rio swap and it was pretty bad on the test drive. It was COLD last night. Tested ECT and it's fine. Unplugged o2 sensor today and drove the car. Problem steadily got worse.
At idle, the car smelled RICH before unplugging o2. I have no catalytic converter so the difference was quite noticeable. However, it doesn't smell rich at idle after plugging o2. Guessing the pcm reverted to a base map of sorts without the o2.
So my theory here is: Fuel starvation causing a leaner condition at part throttle. PCM adjusts but no fuel starvation at idle, thus a rich idle. Tested fuel pressure, 28psi with the car running and regulator hooked to intake manifold. However, revving the car didn't budge the fuel pressure an inch AND with the vac line unhooked, I got the same 28psi steady as a rock. AutoZone tried telling me 68psi was what I was looking for. Uhh then why did that GP Sorensen Regulator I had you look up say 38psi? Mine is weak but still.
So should I be ordering a FPR from RockAuto or what? I'm pretty positive it isn't ignition. I just went through and took care of EVERYTHING aside from the distributor itself and I did check timing this time. It's not a misfire, at WOT it simply won't go anywhere. It's like it is getting fuel, just not enough. And I know the amount of fuel delivery that 10psi changes is pretty significant. RC says a 120cc injector is actually a 100cc with that pressure change. I can see that causing an issue potentially. Sorry for the essay guys, I'm just at a loss here and my Mustang kills me on gas for work. Thanks in advance for any help or suggestions.
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