What the heck is going on, and can anyone help? I turn the key on fuel pump is running.

Pull out the choke, start it, and it will run for 40 seconds to a minute, then just dies.

Most of the time the idle will jump up slightly just before that. It also slows down quickly,

until it no longer runs. It's not a instant thing, total time from idle jump to dead is about

1 1/2 to 2 1/2 seconds. It sounds like it's running out of gas, but the bowls are full the entire

time, and after. After this happens it will restart, but WILL NOT idle. You have to keep pumping the pedal or it dies. One puzzling thing is that the fuel pump is kind of squeaky sounding. It

was replaced last year. When you turn the key on it runs, but has a chirpy tone. This doesn't

seem normal to me?,,,,BB





New parts include...



Rebuilt carburetor

Cap, rotor, wires and spark plugs.

OMP and lines, which finally pumps oil.

Many replaced vacuum lines.

Replaced gas tank, filter by the pump.

All lines coming off the tank.

Fuel pump..

 

When was the last time you changed the fuel filter ???

 

It's in my list of new parts above. Plus I added one between the firewall and carb today. One of those see through ones. The flow of fuel seems to be steady, and no trash visible. I will try replacing the other by the tank again, and see if anything improved.

The tank was so plugged up and rusty it needed replaced, so it never ran off the bad tank, only a line dipped into a fresh gas can. I am thinking it's more of a tuning/emissions system problem now.,,,,BB

 

ive got an 84 b2000 in the shop now that pumps fuel when the key is in "start" but it stops pumping fuel when the key is "on"



it needs the relay, we think, we dont have the book for the truck, and its too old.



but the 84-85 rx7 has a fuel pump relay, it needs to see an rpm signal to turn on the pump....

 

Interesting problem!! But, since I put the clear filter in I can see it flowing. and also watched the bowls keep the same level during the whole thing. It's almost as if something in the warmup cycle is failing to work. Would a overtightened choke do this? I adjusted it some. Should a clear filter "after the pump" be full while it's running? The most it ever gets is about 3/4 full. It stays constant at that level.,,,BB

 

maybe its the ignition?

 

Asked on another site, and everyone there seems sure it's the carb somehow. I guess the only way I am going to know is to take it to the local Mazda shop. I am thankful I have that resource at least!!!! It means towing, but I don't know enough about these cars to even begin repairing it.,,,,BB

 

i had the same problem with my 12A and it ended up being a vaccum leak

 

Get THIS!! I plugged the large(between 1/4 and 1/2") line going into the air cleaner

on the drivers side rear, and it does not die now?? It goes to a vauum pot at the base of the carburetor. Is this the EGR valve?? I imagine whatever it is has a popped diaphram.

which was causing the problem. It still misses and still drops RPM's every 10-20 seconds, but it stays running!!!! I can at least get it to a shop now possibly. I doubt it will pass emissions, but hell anything is possible right??

 

And now it's back to the same old BS. I give up. It gets towed to the shop as soon as I can afford it.