engine not getting ENOUGH gas
#1
engine not getting ENOUGH gas
hey guys i'm back, so i was having problems before as mentioned here:
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/uh-oh-hot-dog-fuel-pump-problem-871749/
and now i'm still having problems...weird huh?
so basically i can tell what's happening is my engine is getting gas, but not enough. i just replaced the fuel filter and fuel pump. so i don't understand why this is happening. any ideas?
oh and btw, i know this because i can get the car to idle by pushing in the afm just a little bit (making the ecu think the engine needs more gas) and it will idle just fine forever if i held it there...as long as i start the engine with some starting fluid
maybe the afm is off? but that's weird
oh and also btw, its a 1990 n/a gtu.
thanks!
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/uh-oh-hot-dog-fuel-pump-problem-871749/
and now i'm still having problems...weird huh?
so basically i can tell what's happening is my engine is getting gas, but not enough. i just replaced the fuel filter and fuel pump. so i don't understand why this is happening. any ideas?
oh and btw, i know this because i can get the car to idle by pushing in the afm just a little bit (making the ecu think the engine needs more gas) and it will idle just fine forever if i held it there...as long as i start the engine with some starting fluid
maybe the afm is off? but that's weird
oh and also btw, its a 1990 n/a gtu.
thanks!
#5
could it possibly be exhaust blockage somewhere in the exhaust? i replaced tps haven't adjusted it but i think the car has to be running to adjust it, which it wont, so i dont think thats the prob. like i said the car idles fine when i press afm in just a bit and hold it there. seems like blockage somehwere
#7
Top Down, Boost Up
iTrader: (7)
Are you jumping the fuel pump test connector (yellow plug on shock tower) and turning the ignition to 'ON'? With the gauge tee'd into the feed line, you should have ~40 psi with the engine off. At idle it should be around ~30 psi, but it will rise back towards 40 psi if you rev it and change the amount of vacuum.
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#8
Are you jumping the fuel pump test connector (yellow plug on shock tower) and turning the ignition to 'ON'? With the gauge tee'd into the feed line, you should have ~40 psi with the engine off. At idle it should be around ~30 psi, but it will rise back towards 40 psi if you rev it and change the amount of vacuum.
stupid rx7. lol.
would it be the fuel pressure regulator? not quite sure what that does.
#11
whats going on?
iTrader: (1)
a fuel pressure regulators job is to restrict flow so that the fuel injectors get a certain psi of fuel going to them. i dont know that if they fail they simply dont hold pressure and allow you to have none.
heres a test... put a vice grip on the hose and clamp it down just enough to barely allow any fuel to get past. or just clamp it down. then.... try and start the car.
#12
no...
a fuel pressure regulators job is to restrict flow so that the fuel injectors get a certain psi of fuel going to them. i dont know that if they fail they simply dont hold pressure and allow you to have none.
heres a test... put a vice grip on the hose and clamp it down just enough to barely allow any fuel to get past. or just clamp it down. then.... try and start the car.
a fuel pressure regulators job is to restrict flow so that the fuel injectors get a certain psi of fuel going to them. i dont know that if they fail they simply dont hold pressure and allow you to have none.
heres a test... put a vice grip on the hose and clamp it down just enough to barely allow any fuel to get past. or just clamp it down. then.... try and start the car.
#15
1200 gone......but......
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I'd start from the fuel pump since you just changed it. Maybe the fuel lines are switched? Pull 1 of the rubber fuel lines off the rail to the injector rail and see if you have any gas flowing.....
#20
Senior Member
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Another question... did you have this problem before you hooked up your new pump? Did you hook the polarity up correctly on the fuel pump? Maybe it is running backwards.
#21
Wait, wait, wait... how did you hook up the gauge? Did you tee it in, or hook it up direct from the pump? Something else to try, is to get a bucket, open the line from the pump, jumper the connector, and see if you have flow. Don't burn yourself down though.
Another question... did you have this problem before you hooked up your new pump? Did you hook the polarity up correctly on the fuel pump? Maybe it is running backwards.
Another question... did you have this problem before you hooked up your new pump? Did you hook the polarity up correctly on the fuel pump? Maybe it is running backwards.
and yeah i had the exact same problem before i installed the new pump. it was pumping but not enough to keep the engine at the idle.
and i know the pump is hooked up correctly. i hear it running, and like i said i pulled the fuel line off and gas flows out fine.
thanks for the help guys
#23
Rotary Freak
iTrader: (6)
Which side of the injectors is your gauge hooked into? If its the non pressurized after the regulator then you wouldn't see any pressure?
Fuel pump to fuel filter to fuel injectors to regulator back to fuel tank...
Gauge needs to be between the pump and injectors, not on the return line to the tank (free flowing back to tank, verry little pressure)... eh.
Your afm could be out of spec too. (dunno why?) Get a volt meter and check it.
Fuel pump to fuel filter to fuel injectors to regulator back to fuel tank...
Gauge needs to be between the pump and injectors, not on the return line to the tank (free flowing back to tank, verry little pressure)... eh.
Your afm could be out of spec too. (dunno why?) Get a volt meter and check it.