Ugh, Me, my dad, and a few of my friend's helped me out puttin in a 350 engine with a corvette T56 transmission in my 91 camaro.

Well, I havent had a decent drive in my car yet.
first, my starter gave out after getting it started a few times.
got that replaced.
and it runs great...

but like a hour later I drove it, the car starts jerking, and constantly dying, and sounds rough.

well, I had my friend that was with me in the car, look and my carb, watch my fuel gauge that we setup with the regulator.

My friend pointed out that after I started up the car, my fuel gauge shows as 3 and then it goes down to 0 PSI. and the car would run for a few seconds and die.

Im running with my stock electric fuel pump with a mallory fuel regulator, we had it set to 5 psi.

I turned my key over and try to listen if my electric fuel pump would make a hum noise, and I get nothing, not a sound.

and every time I start up the car, it shows 0 psi.

I am thinking about going to get a mechanic fuel pump, my engine was drilled and tapped for one, but it doesnt have the rod in it. My friend is worried even if I do get a mechanic fuel pump set up, it wont work right, because I had the builder make me a complete hydrualic roller set up.

any suggestions?

 

There is a fuel pump relay mounted under the hood. On my 1989 Camaro 305 FI Vin E (TBI) it is the second relay from the driver's front fender. It has a 'standoff' that it is bolted to near the firewall. It has five wires. On my relay the fuel pump is energized when the tan/white wire receives +12 volts from the orange wire.

I also have a fuse that the fuel pump requires that is mounted in a covered fuse holder. It is located behind the battery on the end of a protective plastic sheath and it is bolted to the sheet metal. It is a 20 amp fuse. I think this is also supplying power to the ECM. It has power applied to it even when the key is removed from the ignition.

You might check those to see if they are contributing to your problem with the fuel pump.

The 'stock' TBI fuel pump probably supplies a little over 12 PSI and no more than 15 PSI. If you are sending only 5 PSI to the carb then you are returning anything over that to the return hose. Maybe your return hose should be larger than the stock 5/16'' fuel return line. I have no experience with setting the fuel pressure at 5 PSI so I am just throwing out some ideas.

If your fuel pump is 'stock' for a TPI system then you have a pump that is trying to send about 40 PSI to the fuel injectors and thus in your 5 PSI setup it would have to return quite a bit of fuel I would guess. Probably more than the return hose can handle.

Let us know how things turn out.

 

Ok, that sounds good, I'll do that when I get a chance to work on my camaro.
Well, get this, Here tonight, after I get off work, my friend came over, wanted to look at my camaro (He is just obsessed with these cars as much as I do.) well, I decided that I was going to show him the problem I was having with the car, so I gave a little gas for the carb, started up, ran up to a high idle, more then It should, well, I opened the hood, checked my fuel pressure gauge, and it was running up to 10 psi (I was messing with the screw on the regulator to see if my fuel pressure would go up, but it never did.) so I set it back down to 5 psi. and ran pretty good, Already I was surpised the car is still running, so I adjusted the idle speed on the carb, and it was still a little high, but I didnt want it to die out on me.

Well, after letting my car warm up to 195*
me and my friend decided to take it for a quick spin and see if it was going to die.
Strangly, The car was running great, it didnt die out, it had fuel pressure running to 5 like how I setted it, and we drove the car for about an hour and a half, and not one problem came up.

So I am confused here? I wouldnt think it had something to do with electrical, but I really dont know anymore.

I'll try and look around and see what I come up with.
but these things kinda irrate me, because I told my dad to get me a new electric fuel pump and he did, and he has it, but now I dont know if we should return it or keep it. but as for now, I'll keep it and see what happens.

 

Well then I take it your fuel pump WAS functioning correctly yesterday.


Have you had your fuel sending assembly removed to look at the rubber coupler mounted between the fuel pump motor and the hard line that carries fuel outside the tank?

Did you add any fuel to the fuel tank before you went out on the successful drive last night? If so, how much fuel did the gauge show before you added fuel and then after you added fuel?

I agree it might be some type of inconsistent wire or connection problem if the fuel pump works sometimes and other times it does not.

 

We had the gas tank off before, we had to replace the gas cinding unit.
I havent put gas into the car for weeks (I put about 95 octane level gas in my car.) other then that, My gas gauge is showing a little under a half tank of gas.
it could be something electrical, has to be because I started it up this morning, had a little hard time to start, but it was pretty chilly out, so it had a cold start. but it ran fine, I check my gas gauge, and it said I was running 5 psi like it suppose to. well, it died a few times, but it started up just fine after I got after it.

Well, dumb thing is, as I was going to take off to school with my car (school is 30 minutes away from my home.) The freaking car dies on the middle of the street in front of my house. It started up a little harder then it did this morning, but after the 4th time starting it, it didnt start at all, the starter was just turnning the car over and over but it didnt fire.

The car is Unbearable.
x_x

 

I would say you better start using a checklist. Something where you write down if it was a cold start or warm start, dry air or humid air, fuel pressure readings, amount of fuel in the gas tank, etc. I am getting lost as to what is working and what is not working at the exact time you have the problems.

In some regards you are lucky to have the problem show up often. That means if you make the right change you will be able to tell within a short period of time that it made a change for the better.

This could be two problems. Maybe sometimes it is a fuel pressure problem and maybe sometimes it is a carburetor problem. So to make any kind of headway you need to specifically monitor your fuel pressure every time you start the car until it warms up. If you are convinced that the fuel pressure is ALWAYS correct then you can concentrate on other things. Right now I would say that the fuel pressure consistency is questionable. Really watch that like a hawk. Make that your number one focus for now. If you find that if the fuel pressure is correct you NEVER have a problem then you can pour all of your effort into finding a problem there. This might involve running all new electric lines with a proper fuse to eliminate the original car wiring. If your alternate wiring system ALWAYS allows the car to work then you know that you need to dig in and find the true cause of the factory wiring problem. It could be wire insulation that has worn through or a bad ground.

If you follow your factory fuel pump ground wire I believe it will go to a connector behind the back seat, through the back seat to a grounding bolt under the back seat on the driver's side. Then the floor metal takes it to some ground strap someplace where it eventually makes contact with the battery cable that eventually contacts the negative ground post of the battery. So all of those connections should be as perfect as you can make them.

Does it seem that once it is warmed up you NEVER have a problem?

I suspect in Montana this time of year it could be getting really cold at night. I am here in northern Ohio and we are starting to see night time temperatures reach down into the upper 40s once in a while. Is your car left outdoors or in a closed garage at night?

Whatever you do try to make only one change at a time and see if the problem completely disappears.

 

Ok.
My car sits out side, I used to put the car cover over it or put it in our garage, but our garage is still full of engine parts and the tranny and engine is still laying in the shop.

ok, this is what I know,

I turn over the key, and the car will start up (most the time, but sometimes it will hesistate to start.) well as soon as it starts, It dies.
I cant watch the fuel gauge since its under the hood. (the fuel gauge is hooked up to the mallory fuel regulator.
I do not hear no sound in the gas tank, I dont hear a hum or nothing.
When I start it, its about about 30* out in the morning. and it ran fine,
the fuel regulator showed 5 psi.
well, soon as I moved the car, it starts dying out.
I checked all my wires that I know of, didnt find a whole lot ruined or damaged.

Well, my dad has already bought me a new fuel pump (the one in my gas tank is stock, 16 years old and has over 180,000 miles into this car.)
So I think what we will do is drop the gas tank, take out the old fuel pump and hook a hose on where the old fuel pump used to be and use my same old fuel lines.
this fuel pump is about the size of a fuel filter,
but it will work great since its in between of 5 psi to 9.
we're gonna mount the new fuel pump in then engine bay, and hook up new wires.
so that should help it.

 

Check the sticky in the top section of the Carburetor forum for a good way to convert an in-tank electric pick-up to mechanical.

It would be better to mount the new pump back by the tank. They push better than they suck.