Hi all,

I have an '87 P/U with the 3.9L engine. It ran okay till this past Saturday. It's dump run truck that it's poor shape.

It had been sitting for three weeks when I tried to start it. It cranks very well. I'd had problems in the past starting but it always started. Now, it won't start at all.

I've done some reading on the fuel system in this forum but have not been able to find the info I need.

I checked the pump resistance and it's about 23 Ohms. I use my meter to jumper the pump and it pulls about 1.6 Amps.

I have checked for spark going into the distributor cap and it's strong. The coil is about a year old.

The questions I have: What should the current draw on the pump be?

What should the resistance on the pump be?

I have what appears to be the test port on the fuel line. How do test that? I don't have access to a fuel pressure gauge.

It really seems as though it's not getting fuel. Is the pump above the tank? I've replaced the fuel line going to the tank. Can the pump be accessed without dropping the tank?

Someone suggested cutting a hole in the bed to access the fuel pump. I can do that if that would help. Not worried about the bed.

I don't have my code reader - it's at work. Would that even help?

Thanks in advance for any help.

Ray

 

Something is not right here. The 87 3.9 v6 is carbed with a mechanical pump. You sure of the year? Sounds newer with fuel injection

 

GAAAAK! You're right. It's '97. Sheesh!

 

I am more familiar with chevy's then dodge, but I believe the principle is about the same. For openers, take something small and push the Schrader valve down and see if you get a squirt of fuel out of it. Do this after you have tried starting it. There should be some fuel pressure there. If not, you need to get to the wiring going to the pump. Disconnect it, have someone attempt to start it while you check for voltage at the pump wiring. If you have voltage, its probably a bad pump, if no voltage, start checking back up stream, ie pump relay, fuse, etc. To change the pump, assuming its in tank, you have to drop the tank, or remove the bed. Good luck.

 

I changed the title of your thread and moved it to the correct forum for you.

Before you cut a hole in your bed and remove the fuel pump, invest in a fuel pressure gauge. If fuel pressure is good and spark is good, the problem may be that the injectors aren't firing. There is an electronic pickup inside the distributor, as well as one on the top of the bellhousing, but I'm not sure exactly where the injector firing signal comes from. I'm sure somebody here knows more than I do.

In the meantime, have you checked your fuses?

 

Most parts stores will loan/rent a fuel pressure gauge. It just screws on to the test port. You should have near 49 psi.

 

Thanks for moving the thread.



I haven't been able to get to it till today because of two sons in fall baseball and work.

I'll post what I find out today.

Ray

 

I used a meter to jump the fuses and the pump draws 1.6A.

I just had my son try to start it while I pushed the schrader valve in on the fuel pressure port and nothing came out. No pressure at all.

 

can you hear the pump buzz for 2 seconds before start, to prime the system?

 

No, I can't. I had my son turn the key to the run position and nothing. I felt the pump and could feel nothing. I have a new fuse and switched the relay with one that I know works.

There is a set of connectors in the front wheel well that have given me problems in the past.

I could be wiring but when I jump directly to the pump it draws current. Starting to sound like something else is keeping the pump from initiating.

Any thoughts?

Edit:

I do feel it now. I had my son turn it on the pump energizes. I pushed down on the schrader valve in the test port and nothing comes out.