fuel pump wont stop priming

[6SpeedLX]

earlier this week i noticed that my MSD blaster 2 coil was all busted up and decided to replace it...i did and when i went to start the car all i got was loud ticking from the solenoid...i tried jumping the solenoid with a screwdriver and the starter didnt do anything but i could feel power running through it...2 days later i go back out into the garage and the battery had died so i put a battery charger on it. the key was in the igniton in the ON position and i heard the fuel pump prime....and never stopped, it just keeps running....anyone know what might have happened? would the starter solenoid have anything to do with the fuel pump at start up? the car was running fine up until this

 

[HISSIN50]

A latched FP relay or latched EEC relay can cause the FP to stay energized.

I would probe the FP relay socket's terminals to see what values you have at which wires. Post what you have and that will help folks to help you (to determine if the EEC relay is providing the FP relay's positive coil with 12 volts when it should not, etc).

Good luck.

And if the FP relay is the only thing staying energized, one can remove the relay (it is under the driver seat on Pre 92 models; under the hood next to the WOT relay on 92+).

Good luck.

 

[loveblueoval]

I've had this happen to Me before and it was a bad fuel pump relay, and I've use a screw driver to jump the two termanals at the Solenoid with no ill affects before. The PIP senser also controls the fuel pump but I think if it went bad the pump won't run at all. keep me posted if this is'nt it, I still think I can help.

 

[HISSIN50]

I've had this happen to Me before and it was a bad fuel pump relay, and I've use a screw driver to jump the two termanals at the Solenoid with no ill affects before. The PIP senser also controls the fuel pump but I think if it went bad the pump won't run at all. keep me posted if this is'nt it, I still think I can help.

I think you mean the PIP controls injector timing. If it goes bad, the pump runs but the injectors might not fire and one wont have spark.

 

[Don Fiveolio]

Man.....

Sometimes I think my car is possessed. I had posted a thread about this same issue about week ago when I had changed out my battery cables and put in brand news ones. Afterwards, the pump would not stop primeing. Hissin50 suggested that I check the relay under my seat, so I figured that I would do it on the weekend when I have time because I just about live at my job, but I got tired of hopping out the car o disconnect my battery cable everytime I arrived somewhere.

So I get out of work early and dash home to pull the relay before the sun goes down. I pulled the relay and went to search for my volt meter so I could post my readings here to get some input, but after 30 minutes of searching, I gave up and figured I would wait until Saturday. So, I put the relay back in with the battery cables connected and the key turned in the on position and nothing happens. So I turn the key off and then back on and sure enough the pump primed and then went silent until I started it.

I don't know whether to be happy or confused. What happened???

BTW, when I pulled the relay and turned the key, the pump did nothing. Could this mean that it's the EEC relay if there is still a problem?

Steel GT

 

[HISSIN50]

So I get out of work early and dash home to pull the relay before the sun goes down. I pulled the relay and went to search for my volt meter so I could post my readings here to get some input, but after 30 minutes of searching, I gave up and figured I would wait until Saturday. So, I put the relay back in with the battery cables connected and the key turned in the on position and nothing happens. So I turn the key off and then back on and sure enough the pump primed and then went silent until I started it.

I don't know whether to be happy or confused. What happened???

BTW, when I pulled the relay and turned the key, the pump did nothing. Could this mean that it's the EEC relay if there is still a problem?

Steel GT

When one turns the key to the run position, but does not start the car, the pump will prime for ~3-5 seconds and then the EEC removes the ground pulse to the relay and the pump stops priming. It sounds like yours did this after you looked for your meter, and that is normal.

WHen you pull the relay, there is no way for the pump to run - that is also normal. The easy way to kill a pump is just to remove the relay (if the FP relay is the only thing latched. If the EEC relay latched, the many other circuits can stay active and one can come out to a dead battery).

So is it running ok for you?

 

[HISSIN50]

Also, if one thinks a relay is latched, sometimes a light tap on the relay housing will make it unlatch. Just info.

 

[Don Fiveolio]

So is it running ok for you?

Oh yes it is....

Thanks again....Back to the streets

 

[HISSIN50]

Oh yes it is....

Thanks again....Back to the streets

Ok cool. Glad to hear it.
It sounds like the FP relay latched and your removing it jarred it back into action. Might be good to pick up a spare relay and keep it in the glove box (or swap the new one into the car and keep this one in the glove box, since this one is funky, but still works for an emergency).