Well my Brat has started to act up again so I need some help. I have torn down and gone through the carb twice now and replaced the fuel filter. I have also checked my fuel pump which is fine but it still has a bad hesitation problem. Most of the time, it will start up and idle fine after it has warmed up but the instant you give it ANY gas, it wants to die right away until you either back out of the gas completely or you floor it. It will hesitate realy bad until about 4k then it'll be fine. I have new plug wires, cap, rotor, and plugs. I might need to replace a couple vacuum lines but it doesn't have any vacuum leaks from what I can tell. Anyone have any ideas??

Gas tank debri? Hey, you said ideas, you didn't say good ones.

 

My RX would idle fine and could stand and rev, but once you put a load on it, died.

Turned out to be the gas tank.

 

Jay

That mgiht be it seeing this car sat for about 10 years beore it was running again. It seemed to do it worse when I put 2 bucks of Arco gas into it so I could make it a few miles. I since then have put Chevron into it but it still does it:-\ If you stand on it with no load, you can hear it bog down and then rev high

My RX had a sreen on the input side of the pump that had the trash built up in it. It only has the one filter in the front IIRC. Don't know the specifics of you Brat but I would start there and then move to the access panel to the float in the tank. If the hanger for the float is nasty it's probably the tank.

 

Had mine cleared and sealed for 100.00.

 

Jay

I'm not a subaru Guru, but I do know carbs... It sounds like your mixture is way off on that puppy.... You most likely have WAY too much fuel to air.... (causing the bogging, then catching up) As I said, I don't know much about the subaru carbs, but I'm sure the adjustment screws and suggested settings can be located somewhere else on this board.. Another thing you could check, is to hook a pressure gauge to the fuel line where it enters the carb. you should have at least 5psi with the key turned on (that would rule out fuel line/pump problems). Just increase your air screw, give her some more air, and she'll stop choking.

 

Later,

 

Adam

I'm not the expert here, but the stock fuel pump on my '84 Brat only generates 3 PSI of pressure. I think you need to go to the fuel injected engines to get more fuel pressure. Since you have looked at the fuel pump, I assume you replaced the filter there as well as the separator (looks like a filter) in the engine compartment. I'm guessing here since I'm not sure what a '79 Brat has in the way of fuel delivery. With the age of the car, I'd make sure the electrical connection at the fuel pump is good. Lastly, if your car has a vent for the gas tank make sure it is not clogged somehow....as you use fuel, a vacuum builds up in the tank making it harder for the fuel pump to deliver fuel. A quick test is to take a short drive with the gas cap off and see if the problem goes away.

cool thansk guys. I don't think its the idle misxture screw cause I did exactly what the FSM told me to do. Screw it in until she runs really rough, then back it out 2 1/2 turns. I can try it again and I can check the tank too. Thanks again guys:D

 

EDIT: Ed, there is only the fuel filter which I have replaced. There is no seperator, its just a hose that comes into the engine compartment, goes through the filter, through the pump and into the carb:D

No filter by the fuel pump?

there is the fuel filter by the pump under the hood which I have replaced. Ed is talking about a seperator. The seperator came in the EA81, not previous with the EA71 in the gen 1s. I also noticed that when I turn the idle up, the hesitation goes away but when I turn it back down, it come back.....Now I have had this carb torn apart twice so far and I've blown out the jets and all of the little passages inside the carb really well