Fuel pump runs long, low cold idle, low battery

[DryDog]

I have been searching threads but have not been able to find my solution. Hope you all can help

We were in a cold stretch a few weeks ago, -15 F. Everything is sluggish at first in this weather. I noticed one day when I turned the key off that I still heard the fuel pump for a couple seconds. About this same time, the idle wouldn't set itself on a cold start. Instead of being up about 1000, it was closer to 400. I had to keep my foot in it to warm it up. But idles and runs fine once we get going. The X sat in my garage for week while drove my F150 (it has better insulation.) When I got in one day to go for a drive the battery was dead. New bat 11/03. I have been jumping it everyotherday this past week.

Today I pulled off the cables to clean them and the posts, When I put the negative on, I heard the fuel pump run for a couple seconds, with no key in the ignition! Is this noise normal? Or am I just grasping at straws because it is 18 F in my garage and I barely know which end of the wrench to bang with.

So in a nutshell: Low cold idle, Fuel pumps running longer than normal, low/dead battery.

 

[Opera House]

Although the fuel pump relay is known to stick, this could be a problem with the keyswitch sticking. When you mentioned that the pump came on for 3 seconds when the battery was connected, that indicated that the computer was being powered up and then shutting the fuel pump off in a normal sequence. This would also explain the pump running for a while after the engine was stopped. You can turn the engine off because the ignition coil power comes from a seperate switch section of the keyswitch and not a relay. This is done to provide a fail safe circuit to shut the engine off. There is a seperate switch in the keyswitch that powers the ECM relay. This would not be the first time I heard this sticking on. Might want to try some WD-40 in the key to free things up first.

 

[kdogg212001]

i also have somewhat of the same problem, on my 94 xlt when i start it, it will idle about 400 or 500rpm and then i will give it a little bit of gas and then once it worms up everything is fine, so yea any help?

 

[DryDog]

I sprayed WD-40 pretty liberally in the keyhole while I had the bat disconnected, then exercised the switches. I still got the pump noise when I reconnected the bat. Hanes says I need to pull the steering wheel off to get into the column, and for reassembly to replace the nut with a new one. I would like to check that switch, so I guess I'd better stop by Ford after work tomorrow for a steering wheel nut.

 

[DryDog]

Same original problem, new symptom. Today I turned the truck off but the fuel pump continued to run. I could only stop it by dc'ing the battery. I took the steering column apart. On the left is the cluster of switches for wiper etc. I cannot see what controls the ECM. I do feel a rod that extends up the column under the dash that moves in and out when I turn the key. Where does this go and do?

Is the fuel pump damaging the pressure regulator by running w/o the engine on?

 

[Opera House]

The computer would turn off the the fuel pump relay shortly after the crank sensor detected the engine wasn't turning anymore. Looks like the previous information you supplied was incorrect. Looks like you got just a boring stuck fuel pump relay.

 

[DryDog]

For me, boring is good. Where abouts is the fuel pump relay?

 

[DryDog]

Replacing the fuel pump relay solved most of my problem, once I found it. On the '91 it is not in the power distribution box, but under it. I had to remove the air filter box to get to it. There are 3 colored relays there, FP is the black one.

I still have the low cold idle but most of my problem is solved. Thanks for your help.

 

[BONJOVI]

cold weather

During the rough idle on cold starts, did it almost stall on you?

And did you ever get the problem fixed? If so, how? (regarding the rough idle)

I have heard it is often the gasket on the lower intake manifold....