I don't think I'm getting fuel. The Summit guage says 0 psi, yet there is a little bit of gasoline coming out the end of the hose when I remove it from the carb. I had it running for about 15-20 seconds under its own power but could not get it to start again.

I heard somewhere that I have to "bleed" my fuel system but I quickly dismissed that. I am however thinking I need to do something now, because if it ran before and won't run now, odds are something happened.

I thought it was a lack of spark because my timing light stopped blinking after some time, so I pulled the cap off and got the multimeter on the power wire, and it said 12v. I put it back together and plugged a spark plug into the wire and let it rest on the fender and I was getting spark (I dont know how strong it was, i was using an old plug and it was pretty bright out but I definitely saw a spark)


In brighter news, it sounded like a beast for those few seconds.

 

do you have the Mallory three port regulator?

can you hear the fuel pump whine when the car shuts off?

 

In addition to the suggestions above:


Vacuum lines hooked up?

All wiring connected?

Fuel Filter not clogged up?

Plugs/wires/cap/rotor/distributor all attached correctly and in good working order?



My experience has been its usually the little things that screw you. The 305/5-speed I swapped into my convertible wouldn't run for more than 10 seconds, found a loose vacuum line and BAM it purred like a kitten.

 

Yes I have the Mallory. I hear the fuel pump prime when I turn the key to ON, and before I had it all plumbed up there was gasoline coming out, so I believe the pump works. Hell, it worked fine the last time the motor ran. I haven't checked to hear it when the car shuts off but I'm not sure.

This is a TBI to carb swap to anyone who doesn't know.

 

Vacuum lines are fine.
All the wiring that's required is connected (grounds, starter, power, alt)
Fuel filter is old but not clogged.
Plugs, cap, rotor, distributor are all brand new, and wires are a season old- all fine.

Yes, it's these little things that SCREW YOU OVER BIG TIME. Tell me about it. Last year I fought with the 305 for about two weeks, thought it was an ignition problem. Turned out to be a valve lash problem.




How is the fuel pump of a 92 TBI-equipped car controlled via the computer? Would the pump be on when the ignition is on or at least when the car is cranking? If not, then I'll have to hotwire the pump to be on when the ignition is on, correct? Trickster would be of great help on this one.

 

my car had the exact problem that you had, i had to hotwire the pump, im fixing that now that the motor is out.

 

If the FP ga says 0 and you're sure it's connected to the right port, then that would mean you have no fuel pressure.
That seems like a good place to start your troubleshooting.
You need to have a connection from your oil press sender to the fuel pump relay or the pump will shut off after a few seconds.
Don't hotwire that, Please. Just be sure it's wired the right way.
Let us know if that circuit is okay, and well go from there if it is.

My car's a TPI, and I'm not sure if the relay wiring is the same as yours, otherwise I'd go out and pop my hood and look. Besides it's raining.

 

Good thinking- I don't need an engine fire.

But I have the supply line to the side port, the return line to the bottom (bypass) port, and the feed to the carb coming off the other side port with the un-used two ports capped. The guage is in-line to the carb on the feed line.

Where is the oil pressure sender? While I'm down there, where can I wire the electric choke to?

 

With your 305 was it runing with the carb? Or is the carb new?
The old oil press sender from your 305 is the one you should be using, and I'm pretty sure it should be wired to the pump relay just like it was when your TBI was on there.

 

My 305 was running TBI last time. The carb is brand new, out of the box Edelbrock. I don't know where the fuel pump relay is, or anything that I'd need to do, but I do have a Chilton's manual- how vague those can be though, I'm sure you know.

 

That explains why your engine didn't stay running.
The fuel pump is self priming, it runs for a few seconds when you turn the key to on. After that the fuel pump shuts itself off til there's a signal from the oil press sender to the FP relay. It's a saftey feature that should remain, because it's a bad thing to have fuel pressure if the engine is stopped.
Anyhow, work that angle. Your engine started, so the dissy is probably good enough for now.
Try some searches under fuel pump relay and oil pressure sending unit.
Search in electrical forum too. I'm pretty sure you'll find what you need there.
Oh... the oil press sender is at the rear right next to the dissy.

Have Fun

 

Well I got fuel pressure now- problem was that it was out of gas


a bum must have siphoned my tank when I had it parked in the ghetto for two months. I had well over half a tank! I'd imagine that's like gold to the vagrants of downtown Ypsilanti Michigan.



ANYWAY The car runs. I got it. I had to give it a little throttle while it was cranking, but it most definitely fired up and stayed going for about a minute before I had to kill it minor concerns, nothing major. I then went to go celebrate seeing as it was too dark to work any further. Icecream, instead of beer. Hey, it works

 

Yea it still amazes me how my firebird was parked back in December with 3/4's of a tank inside the shop 90% of the time mind you. I go to get some gas from it its bone dry. Good thing the guy that took it doesnt work for us anymore.



Anyway good deal on getting her going but since when does reduced light stop a madman?

 

hahahahaha I'm the last guy who needs reduced or light

gratuitous skinny picture

 

You need to hotwire your fuel pump.

When I first did my TBI to carb swap I hotwired it into my relay. Now I have it hotwired under the carpet by the back seats. BTW be careful what wires you cut. You don't want to hack away anything important...like blower motor wires. But I wouldn't know anything about that ::::whistling::::

 

hahahaha nice


I have it wired to the +12v on my distributor until someone tells me something better to use that's easy to access.

 

I'm sooo glad this is all on record about how all you guys say you hotwired your fuel pump. That way when one of you is the next guy who's car catches fire, I'll simply refer back to this thread. Heh Heh! At least I won't be the guy who told you how to set it on fire.
... But ya know, If you insist on hotwiring the fuel pump anyway, the easy way would be to use the wires that are already connected to your relay.
Just take the one that's supposed to go from the relay to the sending unit and complete that circuit.
On my 85 it's a female plug with a 12ga brown and a 12ga orange at the rear of the engine.
It's been a while so it would be a good idea to double check that, but I think those are the right wires.

 

well after considering it I don't see how the fuel pump being on would hurt anything when the car is on the ON position. I mean, it's on the whole time you're driving anyway, so that's nothing major. If there WAS a car fire I'd rather not be rolling! I'm just going to be sure to clamp down all of the lines extra nicely. I don't need leaky fuel lines that's for damn sure.

 

The reason the factory installed a shutoff switch is so the pump would stop if there's a crash.
The scenario being; the car crashes, occupants trapped inside, driver forgets to turn the key to off.
Without the oil pressure sensitive switch, even though the engine is stoped the fuel pump is still pumping... And there's fuel spraying all over the place under the hood waiting for a spark to ignite it.
Also should the oil press drop too low, it kills the engine before there's any damage.
If you take the time to think about it, you'll have to admit it's a pretty clever idea.

 

Something else. Don't be swayed by some guy who demonstrates how safe gasoline is by tossing a lit cigarette butt into a puddle of the stuff.

 

Good thinking...

 

I'd bypass everything just for a temp fix. At the earliest oppurtunity I would put it back the way it came from factory. That is one safety feature I am not willing to do without. I couldn't care less about ABS and airbags but I like the fuel cut feature.

 

Something about the idea of being trapped in a burning car... YIKES!
But then, just think of what a show you'd be able to put on for all the onlookers.

 

i did exactly what HalfInchWrench suggested when i was 15 (last year) just so i could break in the cam. With the new motor im getting rid of the "fuel pump switch " thats on my dash and going back to the way gm had set it up. my pet peave is doing things "half assed."

ps it looks like you were hungover in the pic. just a guess?

 

you're pretty good


oil pressure switch... how many rpms does it take to get 5psi?

 

this is releveant:
long story short:
i built a new motor.
The oil pressure was low due to galley plugs missing. i fixed it and it now has great pressure. I only ran the motor for the cam breakin and a short drive without the galley plugs. After I fixed it....I took the car for a ride. It got about a mile from the house..and died. When i turn the key on, the fuel pump doewsn't prime or come on. I am worried I spun a bearing and have no oil pressure now, even though I fixex that galley plug problem and that's why my pump won't come on. Could this be accurate, or ois it just the fuel system (i hope)?