Question: 1986 fuel pump

[tedsone1]

I believe my fuel pump had died in my 86. Bought the car several months ago and it has very low miles (71K) Believe I am the first owner in a while that is driving it every day so I have had some issues with the moving plastic parts (windows, antenna, interior stuff) but this is the first engine issues. Started fine this morning but died as soon as I touched the gas. Repeated starts died faster. I figured it burned all the fuel in the line. I found part of a post on line stating that the pump is located at the filler tube assembly and you do not have to remove the tank to replace. Does this sound correct?

 

[BADDUCK]

Yes, you access through the filler door. Test fuel pressure at the schrader valve on the fuel rail. You should see 35 - 40 psi IIRC. Make sure pressure holds after ignition is off. If not, it is likely the pump. If you buy the pump make sure you buy the sock as well. It is sold separately. It would also be a good time to change the fuel filter if it's old. Some kind of service manual will be good if you are going to work on your car. The FSM is best.

 

[vetteoz]

. Started fine this morning but died as soon as I touched the gas. Repeated starts died faster.

I would get a fuel pressure gauge and check pressure at the rail first.
As you say pump may be dying but there are other things that could be causing same no start symptoms.
A injector may be shorted causing the computer to shut the injectors down ,a faulty fuel regulator maybe be leaking fuel pressure off , the one way valve in the tank may not be holding pressure


Pump/gauge assembly comes out the top after you remove the fuel filler door

 

[WillC4]

I didnt think fuel pumps could be dying. I thought they just straight up ceased, meaning even if you turn your ignition, the car still wouldnt start. That was the case with my friend's '93 Camaro Z28.

Aside from the reccomendations from the other members, if your looking/in need for a new pump, you could also consider racetronix, they have a nice fuel pump kit: Racetronix - C469 Fuel Pump Assembly - Kit Configuration Page

Good luck

 

[WRECKER88]

My 1989 Corvette had a stalling problem but would restart for about a year. Then it stalled and would not restart. It turns out my problem was a shorted fuel injector. When there is a shorted injector the ecm will shut the engine off. Each injector should be 16 ohms and is easy to check with a meter. If you find a shorted injector just disconnect it and the engine will start and run. I got a great deal on new injectors from FIC and replaced them last sunday. My car now runs like it did 21 years ago. Good Luck

Fuel Injector Connection

 

[vetteoz]

It turns out my problem was a shorted fuel injector.

As I noted above there are many things affect fuel delivery on a EFI system; not just the pump.
There are basic tests he needs to do to narrow problem down

 

[jnealg]

yep and basic tools he needs as well, in this case a minimum of a FSM, multimeter and a fuel pressure gauge.

 

[aklim]

Yes, you access through the filler door. Test fuel pressure at the schrader valve on the fuel rail. You should see 35 - 40 psi IIRC. Make sure pressure holds after ignition is off. If not, it is likely the pump. If you buy the pump make sure you buy the sock as well. It is sold separately. It would also be a good time to change the fuel filter if it's old. Some kind of service manual will be good if you are going to work on your car. The FSM is best.

I thought it should be 45 with the hose off and the engine running? :confused

Also, I thought that if it doesn't hold pressure after shutdown it is more likely to be the regulator and the way to figure that out is to clamp off the return line?

 

[jnealg]

If you are reading anywhere near 40 the FPR is probably good. if the check valve in the pump is bad then it will drop with the power off. pull the vac line off the FPR and make sure no gas is in the line as it will indicate a bad one also.

I just replaced mine last weekend for the same thing. bad check valve. it pumps 48 with it on now and holds at 40.

these pumps will pump 60+ without a FPR.

dropping PSI could also indicate a leak in the line or leaky injectors. check those as well.