Do Fuel Cut Off switches go bad or maybe something else???

[Mystic 544]

2003 SVT Focus 76K miles

OK - so three times over the last month after going to the gym (about 5 mile trip) the SVT won't start.... twice the pump would kick in and she would start only to die after a couple seconds, the other time no fuel pump noise/no start.
On the 1st two times I checked the fuses (OK) and fiddled with the Fuel Shut Off Switch and followed the ignition to on, wait three seconds, turn off - then wait a couple seconds and turn back over. Both times (it did take a couple tries, but) she started back up and ran with no issues - for about a week.

Today she wouldn't start at home so I once again checked the fuses and fuel pump relay (no idea how to tell if the relay is bad or not???) anyway they checked out, so I pulled the side pannel and pulled that Fuel Shut Off Switch. Wires all looked good and clean and connected. I did notice that something inside the switch does flop around and it made the middle copper bridge thing pop up...anyway I push the "switch" back down, the moving parts go up and down, copper bridge middle part stays in place (not sure if that is how it is supossed to work). OK so I put the keys in and the SVT starts right up...

Any Thoughts????
Oh-She has Never been in any accident.

Another question - still has the original battery and the eye kind of goes green/red and I toss a battery tender on it like once a week over night. Does a weak battery mess with things a lot?

Thanks for the Input/Answers/Suggestions ... I appreciate it!
TimmaY

 

[Mystic 544]

the switch says "Inertia Switch" - guessing that there is a weight or something that moves around inside....I wonder if it makes some sort of electrical or ground connection? Maybe it is corroded or just not making the connection?

As far as the FSOS is concerned - When I called a couple local Ford Dealer Service depts they said they haven't really heard of the FSOS going bad - their 1st thought was the fuel pump Just odd that when I mess around with the switch the fuel pump kicks on (when she decides to start)

Hmmmm, a weak battery and/or bad grounds could maybe cause a lot of start and run problems - Possible that it is causing my start issues???
* She does currently turn over with no issue (has been doing a lot of that all day today Arrgh)

 

[Mystic 544]

... so I had The Original Ford OEM battery tested - came back only 180 Cranking Amps
Hmmm that might be a part of problem lol The new NAPA Legend Premium battery has 740 Cranking Amps
Still had to hit the FSOS after putting in the new battery ... but she has started up OK the last three times tonight.
Guess I will see if things are back to normal going forward!

 

[FORDSVTPARTS]

I just looked and we don't stock the inertia switch, I can't even recall the last time someone asked for one and I deal with more Focus owners than anyone in the country.

That doesn't mean it can't go bad, it's just uncommon, could be a bad pump or any number of things and it's just coincidental that it starts working when you mess with the switch.

Have you tested the switch with a multimeter?

-Steve

 

[RoryBarrett]

Hi Steve , I got all the parts you sent last time. Thanks. Since this guy brought it up how much is a new svt pump, also a new fuel pressure switch ? Thanks

 

[Mystic 544]

Thanks for the reply Steve!
I didn't understand how that FSOS could be the issue either - just odd that somehow it got tripped or was causing the "no send fuel" situation...
The new battery seems to be the solution - heck, overall the SVT runs a lot better and smoother...along with starting right up now:rockon:

Odd that a old battery on its last leg would cause so many issues - Fingers crossed she is all good to go now and I sure hope there is not a dieing fuel pump or switch or whatever anytime soon!!!

:beer:

 

[FORDSVTPARTS]

A bad battery or compromised charging system can cause all sorts of bizarre problems in modern cars because they rely so heavily on proper power supply to all the sensors and such.

Glad it's working for you now.

The '03-'04 pump is $209.59 and the FRPS is $95.14.

-Steve