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95..fuel leak repaired, won't run


premiumpropane
12-14-2005, 01:06 PM
I just dropped my gas tank and replaced the metal fuel lines/interior tree. (remind me not to do this again). I used my old fuel pump as the car was running great prior and during to my fuel line leak which was a steady stream of gas. I can't seem to get it running right now. When just started, it will run fine on idle, even being able to hold a steady 2500 r's or higher. Then it wants to spit/sputter, not stay running. When I can get it into gear it w/it running, it has no power. Is there another filter ahead of the one by the rear wheel well (it was replaced too)? The thing acts like it's starving for gas? I used rubber gas line to splice, is that the problem?? ugghhhh. thanks

randman1
12-14-2005, 08:02 PM
Explain the "I used rubber gas line to splice" in further detail, please. If you replaced the sending unit, it should have connected directly to the three nylon lines via the quick disconnect fittings. Was the splice at the front of the filter where the supply line is steel?

I can think of several possibilities. Fuel strainer in the tank not properly installed, fuel filter installed backwards, supply and return lines reversed. I'm not 100% sure you can reverse the supply and return lines as they were two different sizes on my 97... likely the same on your 95

premiumpropane
12-15-2005, 08:51 AM
Explain the "I used rubber gas line to splice" in further detail, please. If you replaced the sending unit, it should have connected directly to the three nylon lines via the quick disconnect fittings. Was the splice at the front of the filter where the supply line is steel?

I can think of several possibilities. Fuel strainer in the tank not properly installed, fuel filter installed backwards, supply and return lines reversed. I'm not 100% sure you can reverse the supply and return lines as they were two different sizes on my 97... likely the same on your 95

Randman, thanks for the reply, the quick connect fittings connecting to the nylon lines from the metal lines were unusable and the metal lines were all rusted. The new sending unit's steel lines looked like they were made to have rubber hose slipped over them and clamped. So I did that, but I can replace them with steel lines and and compression fittings if thats the problem. The fuel filter is installed the with the flow going to the engine, the fuel strainer in the tank seemed like it only could go on one way since it was elongated in one direction. But maybe I didn't push it on all the way or pushed it on too far. So there are no other filters or strainers on this thing ahead of the large fuel filter under the rear of the car?

randman1
12-16-2005, 02:38 PM
No additional filters... only the in-tank strainer and the in line filter just forward of the fuel tank.

I wouldn't think that the rubber hoses would make a restriction and cause what you are describing. As long as the inside diameter is large enough to fit over the steel lines, you would think it's large enough to support the volume of fuel.

Just for giggles, check to see that the supply and return lines are not reversed. The supply line is the largest diameter of the three coming off of the sender and should be connected to the line that has the fuel filter. The return line is the middle line coming out of the sender and connect to the middle line as they appear fastened to the underbody. The vapor line is the remaining one. If these were reversed, it would cause the fuel flow to be backwards. The regulator would not be able to provide the proper fuel pressure that way.

Can you get your hands on a fuel pressure gauge?

premiumpropane
12-19-2005, 01:12 PM
randman; Thanks again for the reply and I'll crawl under it and check the supply/return lines. I'll also have my buddies mechanic son see if he can bring home a fuel pressure gauge. It should be around 40lbs at that pressure fitting on the fuel rail?

If there was a leak in suction, in the gas return line or the vapor line, would it cause these problems and not have a visible puddle under the car?

randman1
12-19-2005, 07:09 PM
Yep. 40-47 psi is normal. You should see it increase within that range as you open the throttle while running. And yes, use the Schrader valve on the fuel rail.

The vapor line is simply a vent for the tank. Before emission laws, the tank used to just vent into the atmosphere. Now it goes through a valve or two and into the charcoal canister. This can be wide open and not cause any liquid fuel to release nor would it cause a problem for your car ('cept maybe a check engine light for emission related sensors). If there were a leak in the return line, you would have a noticible spray. The pressure in the return line is about 15-20 psi I would guess.

MagicRat
12-19-2005, 07:27 PM
I might add that I rubber-hosed some of the gas supply lines in my '88 Bonneville for several years with no problems, I do not think the presence of the rubber line is the problem.

I might add that ideally a rubber hose is not as safe as a steel line in this application. If you must use one, select one that is designed specifically for fuel injection systems or power steering return lines. They are stronger than the traditional rubber fuel line.

richtazz
12-21-2005, 03:47 PM
You may have a fuel pressure regulator problem at the fuel rail. A fuel pressure tester at the rail is the only way to determine if the regualtor is working. Check for raw fuel in the vacuum line that supplies the regulator, as fuel present in the vacuum line will indicate a bad diaphragm, necessitating replacement of the regulator. The fuel pressure should spike up when the vacuum line is removed, and as vacuum increases (like from a hand vacuum pump), pressure should decrease.

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