Michelon85

Hi all new to this scene. I'm hoping for a little help. So I bought a 1992 Camaro RS that has a swapped 1986 crate 350 that has a carburetor . I got the car to run but won't stay running. I'm thinking fuel/vaccum issues. Here is what happens. Turn the key she cranks takes a second then fires up idles for a minute then dies. Crank again and it takes few seconds starts then shutters and dies. I crank again hit the throttle dies. Crank again slowly hit the throttle revs up to about 5,500 rpm then release it dies. Has a aftermarket fuel pressure regulator on it as well. Any ideas on how to test the fuel pump?

five7kid

iTrader: (14)

Welcome aboard thirdgen.org.

Disconnect the fuel line from the carburetor, run it into a container, start up the pump.

zed-028

how many fuel pumps are on this thing?

in tank pump + mech block pump + regulator
or
in tank pump + regulator
or
mech block pump + regulator

Michelon85

So i disconnected the line from the carb and put in the bottle and turned the key and a small amount dumped into the bottle then after that nothing. Everytime I turned the car off then on would I get a small amount of fuel in the bottle.

Michelon85

As far as amount of fuel pumps all I have seen is the regulator in the engine bay and I know it has a tank pump

NoEmissions84TA

iTrader: (1)

Obviously you have a fuel supply problem.
Fill a small soda bottle with fuel, put the rubber line
from the carb into it, and hold it ABOVE the level of
the carb. Have someone else start the car.
Does it continue running?

Michelon85

No it does not run

Michelon85

I checked all the fuses as well and none are blown or bad

Michelon85

Should I check for voltage at the fuel pump relay?

NoEmissions84TA

iTrader: (1)

Was there enough fuel already in the carb to start it when you did that test?
The fuel needs to gravity feed from the bottle.

You can simulate the same by using an old spray bottle.

sofakingdom

iTrader: (1)

Sounds to me like the fuel pump is being told to prime, but then isn't being told to keep running.

Most likely, whoever hacked in the carb, put in a non-computerized dist (as they should have), left the ECM in place, and left the fuel pump entirely under its control. Which means the ECM tells it to prime when the ignition is turned on. But then the ECM never gets pulses from the dist; therefore has no clue that the engine is turning; therefore never commands the pump continuously on.

Use a 3-terminal oil pressure switch to operate the pump relay... hook the gauge terminal up normally; hook one of the other 2 to ground; and the other of the other 2 to the side of the pump relay coil that the ECM grounds to operate it.

The "5500 RPM" thing sounds like it has a massive vacuum leak, for example, the brake booster port. Solve the fuel problem first, then go to work on the other. One defect at a time. Avoid tail-chasing.

Michelon85

Sofakingdom thanks for the advice but I have no clue where the oil pressure switch would go?

sofakingdom

iTrader: (1)

One of the ports where oil pressure is present.

One is on top of the block, under the dist, behind the intake. The other is on the side of the block above the oil filter.

Rancid87

If I was you I would pull the pump out the tank and run an external fuel pump like a holley red or holley blue. I'd also run some new wiring for it instead of using the factory wiring. Either that or run a mechanical pump. If you do that just make sure you run new fuel line and route it so gravity assists flow so you will not lose your prime.

Michelon85

I would like to run a mechanical fuel pump would be easier then dealing with the one in the tank.

NoEmissions84TA

iTrader: (1)

Both good ideas from sofakingdom & Rancid87.

Michelon85

Yeah and I am thinking of just buying a oil pressure switch for now. I bought this car for $200. Has a '86 crate 350. Not sure what all has been done to it but after bypassing the starter enable relay I finally got it to turn over. Now I'm having this fuel issue. So my question is how or where can I find out how to wire it up? This wiring harness has all kinds of wires disconnected on it. Someone put some effort but never finished it.
I wanna get this ole girl on the road. So do I buy a stock oil pressure switch from Autozone?

Rancid87

If your harness is mostly complete and you find the connector for the oil pressure sending unit/switch you can just jump the terminals with a piece of wire to see if the pump continues to run.

Michelon85

are you talking about the one by dist or by the one above the oil filter?

Rancid87

The one above the oil filter.

sofakingdom

iTrader: (1)

I think someone already told you how:

Which word should I explain more fully?

Michelon85

thanks for all the input I havent gotten a chance to try anything yet my work schedule has been crazy. Thank you though.

zed-028

find a wiring diagram and hotwire the fuel pump through the OBD connection

or

find the wires to the fuel pump and run 12v to it - see if you get a steady stream. if thats the case youve got an oil pressure switch issue.

cannibaljeri

by terminals do you mean the ends of the pig tail for the oil sending unit?

could i just run those wires into the cabin and attach a switch, and have a fuel on/off switch?