Inertial Switch problem or something else???

[Markkuether]

I have a 2005 Ranger with a 3.0 and auto trans. Last Wednesday I was driving with about 1/8 a tank of fuel and the engine suddenly dies while I am on a city street going about 25 miles an hour. I pull over and try to get the engine started again. The starter was turning just fine and there was the occasional studdering but it would not start.

I began to think maybe it is out of gas. I went over to an auto store and bought a gas can, got some fuel and put two gallons in my tank. Then the engine started right up. I then proceeded to a gas station and filled up the tank to the max.

I traveled 150 miles to my parents house for Thanksgiving and there were no more problems that day. However, two days later I was in traffic again in the city and the truck stalled once again. This time it still had half a tank of fuel. I knew then that it was not a problem with the gas gauge. Note that there were no warning symptoms. The truck just stalled at once both times.

I had it towed to a local garage. Earlier today they told me that they found the inertial switch had been tripped. They reset it and it started right up. However we are all kind of wondering if that was the case, then how did I get it started after the first time it stalled?

1. Does this has something to do with just the inertial switch?

2. Or does this have something to do with the fuel pump?

3. If the inertial switch is tripped. will it affect all the power on the truck going off or just the fuel pump?

4. Could having my vehicle towed have tripped the inertial switch somehow and thus the problem is more likely to do with the fuel pump itself after all? In any case, I find it VERY hard to believe that the inertial switch and the fuel pump are BOTH bad. Thoughts?

 

[509lifted]

mine dide that and i had to manually trip the inertia switch and reset it and my truck started up, and that was with a brand new out of the box switch so maybe next time try that? sorry that i can't help ya more

 

[RonD]

A bad inertia switch could be triggered by hitting a bump or tapping your foot to hard on a good song.
You know where it is now so if it stalls again, reset it, drive to parts store, and replace it.

A good inertia switch should trip completely on a collision only(sudden stop or airbag deployment), so engine wouldn't restart without a reset.

And a good switch wouldn't trip by being towed or hitting a bump, nor reset itself, so you could have a bad switch.
I would give the switch a few taps while engine is running, see if engine stalls

 

[Mark_88]

I've had problems with inertia switches before and it had similar symptoms to the in tank low pressure fuel pump going wonky.

It was on my Tempo...if the temperature dropped over night and then rose during the day (which it usually does) in a fairly wide range the low pressure pump would suddenly stop working. This turned out to be a "known" problem with this particular vehicle...

I had the in tank pump changed 4 times in the course of 14 years of driving that car...and although it may not be a problem with Rangers, it does sound similar...the pump would start working after the engine died for no apparent reason...and I found that if I just got out and loosened the gas cap it would start right up...

Hope it is just the inertia switch in your case...but you might want to check out prices and availability on the in tank pump...if your truck even has one...

 

[kimcrwbr1]

Intermittent faults are usually wire/connector related, sand all the grounds and clean the connectors with elect cleaner and use dielectric grease to put them back together. Fuel pump, inertia switch, fuel relay and computer connectors.

 

[tmcalavy]

sounds like you need a new fuel filter or a clean(er) tank...first time you might've pulled the tank down so far that crap/sediment in bottom of the tank got into your fuel filter, second time could've been due to the same, or crappy/wet gas. if the fuel pump is stock it's 7 years old, might not hurt to change it after you check the inertia switch and fuel filter...they play out at the worst time and will leave you afoot.

 

[Markkuether]

Can anyone PLEASE tell me further why my truck started up after it died the first time after I put two gallons of gas in the tank 20 minutes after it died? Two days later, it died again with half a tank of gas and after it was towed to the shop, they found the inertia switch was tripped after all.

I dont want to invest in a new fuel pump if that is not the problem. Quite expensive. Thoughts?

 

[RonD]

As said, a good inertia switch will only trip on a collision, yours tripped when being towed, or that's the assumption.
So it doesn't seem to work like a good inertia switch should, which could mean it will cut power to the fuel pump without tripping completely, which explains the cut out and then restart, maybe you slammed the door just right , to get it working again.

Inertia switch is suspect after tripping for no reason, IMO.

 

[Mark_88]

Can anyone PLEASE tell me further why my truck started up after it died the first time after I put two gallons of gas in the tank 20 minutes after it died? Two days later, it died again with half a tank of gas and after it was towed to the shop, they found the inertia switch was tripped after all.

I dont want to invest in a new fuel pump if that is not the problem. Quite expensive. Thoughts?

The best way to test it is to by-pass the inertia switch for a day or two depending on how frequently it is cutting out.

Just remember that this is a safety feature and disabling that switch can be rather dangerous...but short of that I don't know how else to test it other than to reset it if this happens again...if it starts right up after doing that then you can probably narrow it down to the inertia switch.

 

[snake]

A friend of mine had an '04 that had this exact problem, he went nuts for a while until he found out it was indeed inertia switch related- the wires had gotten pretty hot behind the switch and was starting to make a bad connection.

When you went to go get gas it probably cooled off and that's why it started back up. Electrical bad connections can do some weird stuff. I suggest you remove the switch and check the wiring and connectors behind that damn thing.

 

[tmcalavy]

KISS...you have a fuel delivery problem...assuming the inertia switch was tripped (some shops lie), check the switch, wiring, fuel pump, fuel filter and gas tank...narrow it down until you find&fix the cause.