How to add fuel cut to alarm/remote start?[S13]

[slipnfall]

Hi there, I'm looking for suggestions for adding a fuel cut relay to my 1992 240sx. I am installing a Clifford alarm and remote start next weekend. What's the best way to do this, and still retain remote start and alarm features(in terms of simplicity, integration into the alarm, security).

My alarm unit has an output that is enabled when the remote start is in progress: I originally though I could use this, to enable the fuel pump when remote starting(and disabled all other times). However this wouldn't work when I manually start the car. Another option was to use the factory arm output, but this wouldn't work when the car is remote started, then automatically armed...

Any ideas? I'd rather not have to flip a switch or anything like that. This is an RSX3.5 two-way system FYI.

Thanks!-Jamie

[benemorius]

Use the output from the alarm to activate a relay wired to latch itself which is powered by ign power. When you disarm your alarm, the relay is prepared to activate. When you either turn the key or use remote start, the relay is finally allowed to activate and latch itself. Since it is latched, you may now arm the alarm and keep the fuel pumping to the engine. When the engine is stopped, the latched relay resets so that you must disarm the alarm before being able to restart the engine.

[slipnfall]

Sorry, but I'm not quite sure I follow you: can you clarify your explaination? So I use the GND-when-armed output, to provide ground to the relay coil. The other end of the coil is powered from the IGN. Is the fuel pump(+12V) output on the relay terminals used to latch the coil(w/blocking diode of course)? I understand how to latch a relay, just not clear on how this ties in here.

Thanks!-Jamie

[PoorManQ45]

SOunds a bit too complicated for my liking.

I would much rather have a manual fuel cut switch. That way if the would be thrif manages to somehow defeat the rest of the system, which is all wired together, they still wouldn't be able to start the car.

[slipnfall]

I disagree. While it might be more complex than a switch, if I have to flip a switch to disable the fuel pump(and consequently flip it again to start), it's likely that I won't bother half the time. Also if I can find the switch, then so can a thief. Although I don't underestimate the intellegence of car theives, I highly doubt they're going to fiddle around with wires, trying to find one that activates the fuel pump. In the process they'll likely pop a fuse, hindering them even more. This is of course, after they defeat the starter kill(unless they roll-start it).

IMO, the less I have to do manually means a better chance it will be secured.

[PoorManQ45]

Yeah, but the way I was thinking about it is what happens when someone gets another remote to access your system? All your safe guards will be immediately disabled. That's why I was thinking of having something manual in there too... Just in case...

[benemorius]

This is more or less what I was thinking. Change it to suit your need.

[Florida240sx]

Yea when I get my kit from IAP, and I get the fuel pump going to run extra wire to my undisclosed location.They'll be messing with the rest of my visible switches at which time my alarm will let me know.