LSXvnm

I'm going to be purchasing the ECS e85 fuel system with the A1000 pump on a Hobbs switch and was curious if there was a way to set up a fail safe in case the Hobbs switch failed or had a vacuum line issue?

Maybe after the pump is powered it sends a signal to something? I thought maybe just a green LED in the cabin but by the time I look at that and get out of the throttle damage would probably be done.

junk c5

LSXvnm

What's the reason for 2 Hobbs switches?

g23crawler

See if your tuner can make your car go into limp mode if fuel pressure drops below a certain pressure. I run a fuel pressure gauge for this reason, but usually if you have an external pump you should at least have an afr gauge which would also let you know if you lost pressure.

LSXvnm

Yes but that is turning me into the fail safe lol I need something more responsible than me.

Turbo6TA

Don't ever apply for an airline pilot job ...

CI GS

realcanuk

My aeroforce gauge can sound an alarm on anything it's set too. Even 2 parameters like..... If boost is over 5 lbs and AFR is over 12, for example.

junk c5

realcanuk

I'd say if you use a decent Hobbs switch and proper install, the chances are far greater of the pump failing then the switch.

Running 3 Hobbs on my car and none have ever failed.

g23crawler

I personally know a turner that puts a fail safe into the tune of meth dependant cars. If the meth pump does not turn on when activated it puts the car into limp mode. I would think you should be able to do that with an external pump.

schpenxel

It's not typically "limp mode", it just subtracts a bunch of timing if the IAT doesn't get to the low levels you'd expect to see if meth is spraying, usually. There is a way to fake a flex fuel signal based on methanal pressure to set it up to not add timing unless there's a certain amount of pressure in the meth lines, but not a lot of people go that far (or know how to do it)

As far as doing it based on fuel pump... not with the factory parts. These cars don't have a fuel pressure sensor from the factory so the ECM has no idea what fuel pressure is doing, so there's not really any way to base anything off of that.

I guess if you really wanted to get fancy it's possible to come up with a way to use the same ethanol "tricker" box based on fuel pressure or power to the second pump or whatever, but it's def not a common thing to do or something most tuners have experience with

gotjuice?

I use a Hobbs and also an override switch. I have a green led that turns on when the aux. fuel pump is activated. When running the Mile, I manually turn on the pump.

4head

I've been lurking here for a minute so I thought I'd join to give my 2c.

A great option is to add a wastegate to your cold side. There are a lot of ways to do this, but the idea is pretty simple. You just need to have some sort of "fail" signal (whatever you decide it to be) to tell the gate to open to spring boost level.

It's the strongest fail safe system you could involve. One way to do this is with your AFR guage, some like the AEM Uego can be programmed for fail safe signals, and then use an EBC to pull boost. I'm going to keep it vague because there are a lot of ways to do this, some can be on a really low budget, some can be baller and fancy. Just depends on what all you want it to do.

EDIT:
That is assuming you're running a blower obviously. You can also use this to pulley down and bleed boost, or to use an AMS1000 boost controller to do a nice boost by speed. Waste-gates on cold sides of blowers has been around for a hot minute, and are really helpful for all sorts of things.

jayyyw

AEM sells a Failsafe gauge that reads boost and AFR.

4head

Oh damn that's cool. I had their meth gauge and wide band and both had fail safe abilities. They make good stuff imho. If you run meth you'd be silly not to get their water meth fail safe gauge. It does high flow low pressure, high pressure low flow, no flow, etc all different kinds of failure (line coming loose, pump not coming on, etc)

Shortpersonbk

If pressure is to drop as much as your main pump not turning on no fail safe that does not involve computer interference is saving it on time. The AEM standalone gauge cannot cut boost it can just send a signal that the oem ecu can do nothing with no matter how you set it up as far as i know. Only way you are getting good fail safes imo is with a standalone and adding pressure sensors.

4head

1) If your pump didn't come on, there would be no pressure in the line to start with, so that makes no sense
2) You can take that signal and wire it to a boost controller. Only a moron would wire it up to something that "can do nothing with no matter how you set it up".Several modern electronic boost controllers have the ability to drop pressure to gate, when it receives a fail safe signal. Also there are ways to setup a bypass, that's triggered by a signal, between the boost control solenoid and the manifold. That way the solenoid drops the gate to pressure.

Stand alone isn't the only way to get good fail safe's working. You just have to think through every step, and buy a couple of extra parts. A lot of this stuff has been discussed many times on many applications with turbo's and blowers. You can spend 10 minutes on google and find many ways to skin the cat.

Shortpersonbk

1.) He is talking about running an external pump on the side of his intank pump. So there will still be the pressure from the intank pump until it gets run down from not being enough.
2.) If he has a turbo a expensive EBC in combination with the failsafe gauge would work as long as when it drops pressure and runs on gate that the gate power isnt to high for the intank pump which more then likely is stock given that he is adding a large external. I am not sure how you would do this with a blower i know a gate on the cold side has been mentioned but again gate pressure would need to be under what the stock pump can handle which then would limit how much boost you could run on the high side without pushing the gate open. There is a point here where your invest so much time and money in a hacked fail safe for a issue most do not have that you are even playing field from just hurting the motor and fixing it should it happen.
3.) When i say you cant wire it up to anything I am saying people above are saying to trigger the check engine light or sound an alarm...which by the time a human can react more then likely damage is done. Computers tend to react a little faster.

4head

I see
I miss understood that he was talking about a meth pump for some reason.
My mistake.
I agree with you 100% about hooking it up to a light is just too little too late.

With a 4 port solenoid you can run a lot more boost over wastegate spring. I think the accepted numbers are 4-6x wastegate spring. So if you have a 5lb spring you can run 20-30lbs. Some even advertise 7x wastegate spring. I doubt many blower cars are running 30psi, so I'm willing to bet you can get a spring in there that's low enough to work on the stock pump, especially considering most of the higher hp blowers are going to be way out of efficiency at ultra low boost.

Or you could come up with a way to cut all spark all together on fail safe signal.

Like I said, there are a lot of options out there. I'm not interested in doing anyone's home work, so I'll leave it at that.