Fuel pump stays on with ignition in 'on' position!

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R.J.
Helpful MS/Extra'er
Posts: 66
Joined: Sun Oct 23, 2005 10:31 am

Fuel pump stays on with ignition in 'on' position!

Post by R.J. »

Here's my situation. I hope someone can shed some light on this for me. Yesterday, the wire that goes into the MS unit for the fuel pump relay came loose. I re-attached it and now I notice that my fuel pump stays on when the key is in the on position. I used to hear the relay click on, then the fuel pump would prime and then the relay would shut off and the fuel pump would shut off. Now, the relay clicks on and the fuel pump stays on. Does this should like a bad fuel pump relay? Is it coincidence that it happened when the fuel pump wire came loose? Most importantly, will this effect the car when running? I wouldn't think that it would effect the car while running. The only negative effect that I can see is if the car is left in the on position, it will flood the engine. Please help me out. thanks.

-RJ
buncey
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Post by buncey »

hi R.J

im getting the exact same problem,. fuel pump runs constantly without priming and going off after 2-3 secs,

if i dissconnect m.s completly the fuel pump dont run, so i know it must be a problem with the m.s

i even tryed upadaing firmware like other did but i dident work.

so far i have not worked out whats the problem, if you find out the problem R.J please post what is was mate.


also is there anyone here that can help us, solve this fuel pump problem :(
jsmcortina
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Post by jsmcortina »

This could occur if the transistor on the main board that drives the fuel pump relay got damaged.

James
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buncey
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Post by buncey »

ok any ideas why transistor it is ?

can only see q2 and q7.
R.J.
Helpful MS/Extra'er
Posts: 66
Joined: Sun Oct 23, 2005 10:31 am

Post by R.J. »

Would something outside MS cause this problem? It just seems a little wierd that all of a sudden it happened. Or maybe since the fuel pump wire came loose on MS it ruined a transistor when it got re-connected. Any ideas?
buncey
Helpful MS/Extra'er
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Joined: Thu Jul 13, 2006 8:11 am

Post by buncey »

only other thing it could be outside m.s is ur relay did u change it for another.
R.J.
Helpful MS/Extra'er
Posts: 66
Joined: Sun Oct 23, 2005 10:31 am

Post by R.J. »

I figured out why the fuel pump was not shutting off. When the wire came loose, I hooked it up to the wrong pin. It's working correctly now. Hope you figure out your problem buncey.
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