83 RX7 Dying *only* while driving
11-07-20, 11:48 AM
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83 RX7 Dying *only* while driving
Hi, i recently picked up my new to me 83 FB, it's got 137k or so miles, supposedly rebuilt motor 40k ago
But on to the main reason for the thread,
i was driving it home after buying it, drove great for an hour, then it sputtered like it was out of gas, and died, i let it sit for a second, turned it back on, and it acted like it never happened, previous owner says it never did that to them, and based on the whole hour of driving where it did excellent, i'm inclined to believe them, but anywho
it then died again, this time after about 5 mins of driving, repeat x5, each time sputtering sooner and sooner, now first question is gonna be "is there any gas in it" i filled it up entirely about 10 mins into the trip, and the gas gauge reads half right now, the p/o says the gauge has always been accurate, so i see no reason to assume i'm completely out of gas.
i had it towed the rest of the way home and decided while trying to fix it, i wanted to upgrade some things i see talked about on this forum, so i went all in and:
Installed Carter fuel pump
replaced the rubber hoses in the fuel pump area
Rebuilt carb, and stripped what little bit hadn't been stripped by p/o (rats nest is already gone)
Installed a Holley FPR w a gauge, set to roughly 3psi
New rubber fuel lines in engine bay
New NGK sparkplugs
HEI direct ignition swap, two brand new coils and hei modules for each leading plug, trailing now running stock but in leading position on dizzy
New dizzy cap and rotor
New plug wires all around (NGK 7mm on trailing, ACCEL 8mm on leading)
Now after all of that, it starts immediately, idles pretty smooth (little stumbly at times but did that when i got it as well) and drives excellently!.....until it stumbles and acts as though it's out of gas....again...and might i add, it will idle perfectly fine for however long i leave it running, but as soon as it's moving, i make it about a quarter mile before it sputters
now i wasn't attempting to shotgun approach the fix, moreso upgraded what i felt had to be lacking on a 37 y/o rotary, and figured one of the things would be the fix as well as an upgrade, but now i'm just sitting here scratching my head, as the ignition system and fuel system are pretty much new aside from the fuel tank, metal lines, and rubber lines at the top of the fuel tank.
So, basically, any ideas why it might still be sputtering? Sorry in advance for anyone who had to read this wall of text 😅
But on to the main reason for the thread,
i was driving it home after buying it, drove great for an hour, then it sputtered like it was out of gas, and died, i let it sit for a second, turned it back on, and it acted like it never happened, previous owner says it never did that to them, and based on the whole hour of driving where it did excellent, i'm inclined to believe them, but anywho
it then died again, this time after about 5 mins of driving, repeat x5, each time sputtering sooner and sooner, now first question is gonna be "is there any gas in it" i filled it up entirely about 10 mins into the trip, and the gas gauge reads half right now, the p/o says the gauge has always been accurate, so i see no reason to assume i'm completely out of gas.
i had it towed the rest of the way home and decided while trying to fix it, i wanted to upgrade some things i see talked about on this forum, so i went all in and:
Installed Carter fuel pump
replaced the rubber hoses in the fuel pump area
Rebuilt carb, and stripped what little bit hadn't been stripped by p/o (rats nest is already gone)
Installed a Holley FPR w a gauge, set to roughly 3psi
New rubber fuel lines in engine bay
New NGK sparkplugs
HEI direct ignition swap, two brand new coils and hei modules for each leading plug, trailing now running stock but in leading position on dizzy
New dizzy cap and rotor
New plug wires all around (NGK 7mm on trailing, ACCEL 8mm on leading)
Now after all of that, it starts immediately, idles pretty smooth (little stumbly at times but did that when i got it as well) and drives excellently!.....until it stumbles and acts as though it's out of gas....again...and might i add, it will idle perfectly fine for however long i leave it running, but as soon as it's moving, i make it about a quarter mile before it sputters
now i wasn't attempting to shotgun approach the fix, moreso upgraded what i felt had to be lacking on a 37 y/o rotary, and figured one of the things would be the fix as well as an upgrade, but now i'm just sitting here scratching my head, as the ignition system and fuel system are pretty much new aside from the fuel tank, metal lines, and rubber lines at the top of the fuel tank.
So, basically, any ideas why it might still be sputtering? Sorry in advance for anyone who had to read this wall of text 😅
11-07-20, 08:05 PM
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it has a Holley inline filter before the fuel pump, p/o says it was almost new, when i was replacing the fuel pump it certainly seemed new, i also added a fuel filter past the FPR and before the carb
11-08-20, 10:13 AM
#4
well, the way i see it is a filter probably costs more in time than it does in coin, and it's a simple fix if that turns out to be the issue.
that said, the next things i would take a closer look at would be:
1. the tank (maybe it's dirty. perhaps the filter inside is toast???)
2. the floats (you mentioned that you rebuilt the carb, so maybe there is something amiss)
3. maybe play around a bit with the pressure and see if it helps or makes it worse
that said, the next things i would take a closer look at would be:
1. the tank (maybe it's dirty. perhaps the filter inside is toast???)
2. the floats (you mentioned that you rebuilt the carb, so maybe there is something amiss)
3. maybe play around a bit with the pressure and see if it helps or makes it worse
11-09-20, 04:16 PM
#5
Sounds like dirt in the first filter (between tank and fuel pump) or in the tank itself. Common problem with these 40 yo cars. The inside of tank starts to rust and flake, and those flakes swoosh around in the bottom if the tank - especially as the fuel gets lower and lower.
11-09-20, 04:31 PM
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Sounds like dirt in the first filter (between tank and fuel pump) or in the tank itself. Common problem with these 40 yo cars. The inside of tank starts to rust and flake, and those flakes swoosh around in the bottom if the tank - especially as the fuel gets lower and lower.
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