So last weekend i purchased my first car as a small winter project. Its a 1990 Camaro rs with a tbi v8.

I'm not getting any gas to the throttle body. When i turn the key i can hear the pump 'prime' as it goes for 2 or 3 seconds but i get no pressure that i can tell of and no gas up to the engine.

I replaced the fuel filter and made sure gas was able to flow out of the tank, which it does.

I don't know where to go from here, very new to working on cars and would appreciate the help! Looking to have the car running good for prom!

 

Hearing the fuel pump does NOT mean you have a pump working.

 

Ok so if the prime doesn't mean that the pump is working properly how do I test to see if it is?

 

Fuel pressure test.

 

just curious have you lost spark as well ?

 

I do have spark, replaced the distributor cap, button, and all spark plug wires. As far as i can tell I'm getting no presser through the lines. I have the back end of the car jacked and on stands so gas has gravity fed itself to the throttle body through the lines so a block in the line is ruled out.

 

Fuel pressure is measured with a pressure gauge, not gravity. An auto parts store should have a loaner you can use.

Verify pressure with a pressure gauge.
Fuel should spray from the injectors while cranking.
verify injector signal with a Noid light, plug it in place of one of the injectors, the light will pulse while cranking the engine.
Having verified pressure, and injector signal, and you still don't have fuel spray.
Check for a blockage at the inector, or the injector itself is faulty.

FYI
Holding the gas pedal all the way while cranking will cause the computer to disable the fuel injector signal, it does this because it thinks you are trying to clear a flooding condition. Never press the gas pedal while starting the engine.

 

Alright, SO

I tested the pressure, I have none.
I tested the injector signal with a noid light, Everything was good there.
Injectors are clear.
New fuel filter is installed
The fuel line is not blocked.
The relay is good.
The engine runs perfectly when ether is sprayed into it.

I bypassed the relay to see if the pump would run by connecting the gray wire with the orange wire while the key was in the on position and i can here the pump running as long as i keep the connection together but i get no gas.

There is 6 gallons of gas in the tank that i know are FOR SURE there so there is gas to pump if the pump was working properly.

SO is it safe to assume all wiring and connections are good and its time to replace the actual fuel pump?

 

Nice work Sherlock !

 

Sounds like you may have a split in the hose between the pump and the sending unit. GM also liked to used a funky "damper" in this location that would come apart.

Understand also, the TBI operates between 9-13 psi fuel pressure while the port injected engines operate between 35-45 psi(higher pressures in later years). The larger of the two lines is the pressure or supply line, the small line is the return line back to the tank.

 

It's time to drop the tank and see what is actually keeping the pump from building pressure.
FYI - There is a fuel pump relay bypass built into the ALDL connector. Supplying 12v to the G-terminal will power the fuel pump.

 

I hope this doesn't make anyone want to cringe but i was able to cut an access hole in the truck to get to the pump without the whole mess of removing the fuel tank. Very clean and a lot simpler access! especially if the replacement pump goes out in a year or two! Tomorrow I'm going to finish disconnecting the piping and change the filter! Hoping everything goes smooth. Never realized how much i hate gas until this past week!!

 

Looks like your still going to have fun trying to remove it.

 

Don't cheap out and buy a shitty autozone pump or you will be replacing it again soon. Buy a quality replacement pump.

 

On my 92 camaro the hose that held the fuel pump the the fuel pump assembally had actually melted. Sounds like that couldd be your problem also. Also I second that a access panel probably wont work as all the lines coming out the top are metal. I was able to change mine without pulling the rear end though on a positive note but it was still a pain!

 

That looks pretty rusty. Use plenty of penetrating oil on the lock ring so it doesn't get torn up too bad coming apart. I second that the hole you cut isn't going to help as much you may think. The steel lines go down and off to the side of the tank. Not alot of flex there, plus you just cut up your car's body. I have replaced many of these pumps the correct way. The hardest part is disconnecting the exhaust to remove it. As long as the exhaust pipes come apart okay, the pipe comes out with a little help and then you just disconnect the rear shocks from the axle and let the axle hang down as far as it will. Detach the rear brake line block from the body to avoid overstretching the rubber hose. With the axle down out of the way, the tank comes right out conce the lines and electrical are disconnected. This way you can clean up and inspect the tank for the best install. The only decent way I know of avoiding dealing with a future tank drop is to install external pumps.

 

The access hole worked wonderfully! Had to undo the bracket that holds the fuel tank on (two bolts) and the suspension bar that went across the back (3 bolts) but that let me drop the fuel tank slightly to slide the fuel pump and metal fuel lines out nice and easy! The tube that connected the pump to the fuel line had melted in the tank. Also the fuel line under the body (connecting the tank to the fuel filter) was so rusted that it cracked when i accidentally bumped it with a wrench. I was able to replace all metal lines (running from pump) with high pressure rubber fuel lines. I double clamped the lines on both ends. Looks a lot cleaner! Have absolutely no leaks. Bolted everything back together it fits like a dream. Turned the key got fuel to the throttle body, it fired right up for the first time in 6 years. let if run for about a half hour, was letting out clean exhaust, the fan kicked on right when it was supposed to.

I did not want to take the tank out the "proper way" because there was a lot of bolts that were rusted completely over and did not want to risk stripping them out.

Car runs very quiet in idle no clicks or ticks at all. Revved it up a little everything sounds and looks good!

Thank you to everyone who helped me get this figured out! I REALLY appreciate your time!!

 

Thats awesome that everything worked out for you with the fuel proplem. From that pic i could tell that you would have to drop the tank a little bit to gain more room to be able to pull the pump. So now that you have it running i have a question. Did you change all the fluids in the car yet?

 

Not yet, Oil is a little dirty but level is good. Broke a hose on power steering, and broke a brake line in the back so those are the next two projects. Tires are dry rotted and wont hold air for more then a day. Driveside rear shock is broke and needs replaced. Don't plan on letting it leave the garage for another two months at least. I mean the car has not been driven since 2005 but for 800 dollars what can you expect? Other then these problems it has less rust on the body then my 2004 caviler and just needs a little TLC. Are there any fluid that you think i should replace immediately?

 

Glad to hear that it's running. One more classic third gen back on the road.

 

zgoist119-- What did you use to cut the access hole? I am concerned about sparking coming from my Dremel's cutting wheel.

 

Rightwing, I used a cutting wheel to cut my access flap. There is about an inch between the body of the car an the actual tank so as long as you are careful and take your time keeping in mind that the gas lines leave the top of the tank from the side closest to the front of the car.