Alarm with Fuel Pump cutoff?

[1991S13]

A boy in my class was talking about an alarm he bought for his Integra that shuts off the fuel pump if anyone tries to steal it...but he didn't have a name for it. I wouldn't mind getting one, if it even exists, so can anyone tell me what kind of alarm this is?

[PoorManQ45]

That's not a bad idea for disabling the car. But as usual, I don't really like security systems that disable the car from starting. I mean, what happens when the security system somehow gets "stuck in the disabled mode? You're basically screwed until you bypass the disabled systems.

ANyway, I do understand the purpose of the system. Which is to stop would be theifs.

If you want to disable your fuel pump, I would suggest that you just find out where the fuse for it is. Find the wire for the fuel pump right after the fuse box. cut that wire. Then connect a length of wire long enough to reach a "hidden" location where you can mount the switch. Mount the switch, wire it up, and there you go, you have a custom CHEAP disable system.

[1991S13]

Thanks man, thats awesome. What wire would you recommend? I dont really know much when it comes to electrical, but is there some special kind I would need?

[PoorManQ45]

I like to use nice Cheap Walmart 14 gauge speaker wire. It costs ~$10 for a 50ft spool.

I don't know about your specific car. So if you need help locating the actual fuel pump wire, you might need to ask someone else

[elwesso]

If you wanted something either craftier you oculd bypass the relay, so that it wouldnt be easy to possibly bypass it.....

Just an idea.....

[1991S13]

After you gave me the idea I consulted my grandfather about it (man is a 70 year old genius, lol). He was like yea, my brother had that on some old car he had back in the day. He said he's got the wire, so Im gonna pick up a toggle switch and we'll get it done. Thanks a lot.

[PoorManQ45]

Woot WOot. I bet your grandfather either had a muscle car, his friend did, or his son did

[1991S13]

I don't remember what my grandfather had...

Uncle had a Grand Tourino with some Chrysler engine special built for the NYPD, you could put in an 8-track tape while sitting still and when you floored it it would shoot the tape back out.

Dad had a '70 Charger with a built 400. Pretty bad a**, but he sold out and traded it on a newer Ford truck back in the 80's when the 4x4 craze hit.

So yea...I got some mad hp in the family tree.

[Jookmasta]

the cliffords that came before the matrix series had a fuel cut off thing built into them. ya they work cuz if the code isnt punched in within 20 seconds of the engine running, the car will cut off and the alarm will blare.

[meticulousmobile]

fuel cutoffs are a bad idea in general. A well done starter kill (or ignition kill in a manual transmission) works better.

[PoorManQ45]

Why do you think that a fuel cutoff is a bad idea? It is the same thing as a starter kill swittch.

Except, the car will start and run for ~5~10 seconds and then shutoff.

[meticulousmobile]

Just because it lets the engine start and run, and then lets the engine die the same as if you ran out of gas. It's not the worst thing you could do to your car, but there are better options that are very secure if installed correctly.

[PoorManQ45]

Yeah, I know what you're saying, But as you will soon learn, I am PoorManQ45. I like to do things myself for less then it would cost to buy an already built kit.

I personally would combine a starter kill switch will a seperate fuel pump cutoff and hide the switches in seperate locations so that if one is found, the car still won't run.

[Rex]

Yeah, I know what you're saying, But as you will soon learn, I am PoorManQ45. I like to do things myself for less then it would cost to buy an already built kit.

I personally would combine a starter kill switch will a seperate fuel pump cutoff and hide the switches in seperate locations so that if one is found, the car still won't run.

If you're gonna go that route, put 3 relay switches in place that require a specific combination of open/close to allow for starting and be done.

I'd rather mess with strictly eletrical, than fuel and eletrical.

[PoorManQ45]

If you're gonna go that route, put 3 relay switches in place that require a specific combination of open/close to allow for starting and be done.

That's too complicated, I can't remember what I had for breakfast and you expect me to remember the order to flip switches?

I'd rather mess with strictly eletrical, than fuel and eletrical.

That's the thing, I am talking about only electrical cutoffs. You wouldn't actually cut the fuel supply, you would just cut the power to the fuel pump.

[Rex]

... That's the thing, I am talking about only electrical cutoffs. You wouldn't actually cut the fuel supply, you would just cut the power to the fuel pump.

And it would cut off???

Therefore, you would in effect be messing with the "fuel", I'd rather just stop the spark. Yes, this could result in a soaked/flooded condition, but (my guess) they aren't gonna try that long, if it never turns over/starts.

[PoorManQ45]

And it would cut off???

Therefore, you would in effect be messing with the "fuel", I'd rather just stop the spark. Yes, this could result in a soaked/flooded condition, but (my guess) they aren't gonna try that long, if it never turns over/starts.

Oh sorry, I thought you were thinking that we were talking about an actual valve to cut off the fuel.. Oops.

Yeah, I know what you're talking about now, but you stated the one major flaw with an ignition cutoff. You run the risk of a hydralocked engine, and if the would be theif just left the car there, you would be non-the-wiser, unless they broke glass of course.

I think an ignition and fuel cutoff switch would be the way to go for both theft deterent and engine health.

[Rex]

Just showing my age ... I think flooded, not hydra-locked.

[PoorManQ45]

Hmm, well, when the cylinder fills up with fuel, isn't that called "Hydra-locked"?

Either way, that's a recipe for a bent rod if you try to start the engine like that

[Hellion240sx]

sorry about the double post but i figured why i wasn't getting any email responses to the topics i was replying in. i thought it was automatically done? eh well i know now you have to check the little box!

back on topic VVVV

[Hellion240sx]

If you're gonna go that route, put 3 relay switches in place that require a specific combination of open/close to allow for starting and be done.

I'd rather mess with strictly eletrical, than fuel and eletrical.

aight i dunno what just happened buut... ok thats exactly what i have been wanting to do but wasn't sure if it was possible! i like the way you think rex! can you explain a little more how that would work? thanks

[hannibal]

I understand fuel cut (place a switch in the power line to the fuel pump) and starter cut (switch in the power line), but what exactly are you switching in an ignition cut??Are you switching on and off the power to the coil??

[PoorManQ45]

Yep, you answered your own question .

Cuts the power to the ignition system, ie spark plugs

[Silvia2b]

I forgot to eat breakfast this morning, skipped it and went straight on to lunch. That seems to be my problem too. For instance I'll wire some complicated sequence of alarm channels to transmit while operating vehicle circuits and guess who ends up looking like a dumb *** when the alarm is going off and the car doesn't start, airhorns and horn is honking for 15 sec. while I try to remember the sequence. But at least I have comfort in knowing a professional whould encounter the same difficulty in an attempt to unlawfully remove my car fro the designated parking spot that I chose. I have since simplified the process with my newest alarm/ security network.

[PoorManQ45]

^^^

[Hellion240sx]

whenever your ready rex

[Rex]

whenever your ready rex

Sorry, I had stayed away fromt his thread in general .

If you think about each switch either being open or closed, lets use pluses and minuses for example the switches could be in the following positions

- - -- - +- + -+ - -- + ++ + -+ - +etc with only +++ allowing the car to start. You would just have to know the right sequence. Keep in minid these three switches could be located at various points of the car.

[Hellion240sx]

rex your a genious. now i gotta get y boi to look at this cuz he'll undrestand it more thna i ever will. lol.

[PoorManQ45]

Sorry, I had stayed away fromt his thread in general .

If you think about each switch either being open or closed, lets use pluses and minuses for example the switches could be in the following positions

- - -- - +- + -+ - -- + ++ + -+ - +etc with only +++ allowing the car to start. You would just have to know the right sequence. Keep in minid these three switches could be located at various points of the car.

What type of circuits and relays would you have to use to get that kind of effect?

I mean, what I got from what you said is basically you're going to be putting in three seperate switchs, that's it. Could you extrapolate a little bit please?

[Rex]

What type of circuits and relays would you have to use to get that kind of effect?

I mean, what I got from what you said is basically you're going to be putting in three seperate switchs, that's it. Could you extrapolate a little bit please?

Just put them "in-line" in any circuit that is required to start the car. It could be bewteen the key tumbler/ignition adn the starter for instance.