I'm curious about a "nitrous" style engine kill button

[MetroMPG]

See http://metrompg.com/posts/coasting-e...-vs-idling.htm

Restart with the key, if the car's automatic (and if the transmission is the type that won't be damaged by engine-off coasting). Clutch start if it's a manual transmission.

Again, this is not something I'd recommend for every driver or car. Safety & durability issues. Buyer beware.

[COMP]

Originally Posted by MetroMPG

See http://metrompg.com/posts/coasting-e...-vs-idling.htm

Restart with the key, if the car's automatic (and if the transmission is the type that won't be damaged by engine-off coasting). Clutch start if it's a manual transmission.

Again, this is not something I'd recommend for every driver or car. Safety & durability issues. Buyer beware.

if i was to add the kill button i'd add a start button to the system to ,,or a momentary (sp) toggle/rocker switch

[8307c4]

Originally Posted by Volones

My desire is to keep my changes as "invisible" to another driver as possible.

I like the way you think, stealth econ, less raised eyebrows.

The shut down isn't too awful, it's the starts that kill it for me.

But I also believe the dash shut-off isn't all that good, not so much because we don't have gauges (maybe that too) but electronically speaking.
And, less power fluctuations wouldn't be harmful.

[JohnnyGrey]

Interrupting the crank sensor is not a good way to go. Some cars, like mine, have both crank and cam sensors that are somewhat redundant, but are also used to make sure the crank and cam are in sync. If you interrupt the crank sensor, the engine will continue running on the cam sensor and will complain about the crank sensor. If you interrupt the cam sensor, the engine will run on wasted spark, revert to batch injection mode and will complain about this, but it will keep running. Plus, you don't want to set a CEL if you don't have to.

[COMP]

it would throw a code

[Volones]

Originally Posted by 8307c4

I like the way you think, stealth econ, less raised eyebrows.

I actually meant to other people that drive my car, sorry for the confusion. I'd be happy to advertise to other traffic what my MPG is. I even intend to put stickers on my rear wheel skirts showing the improvement in mileage they are responsible for.

As for the switch (back to the topic), I played around a bit with the steering column, and am pretty sure I can splice the relay inline with the main ignition wire, so as far as the engine is concerned it would be just like turning the key off, but the rest of the dash (gauges, lights, etc.) wouldn't be affected at all. I'll have to review the schematics a bit more to know for sure, then take a trip to the electronics store.

[RH77]

Regarding the fuel pump cutoff.

I know I argued against it, but in the essence of "Full Disclosure", I had an interesting experience.

I replaced a fuel filter on a '95 Merc Mystique last weekend -- the process to relieve the fuel pressure in the line was to pull the fuel pump fuse and start the car until it stalled.

Much to my surprise, the car immediately stalled within 2-3 seconds.

(meanwhile, replaced the filter and the fuse)

Turned the key to on, heard the buzz of the pump for a second or 2, and the car started right up.

Pre-OBDII and no codes.

I haven't tried it on the 'Teg -- should there be a concern with the injectors trying to pump diminishing fuel supply (or lean-issues)?

Side Note: For those interested in buying a used car...

I don't know what team of "experts" designed the Contour/Mystique Zetec 4-cylinder. When rigorously maintained, it's an efficient engine (easy to attain 30 MPG). There's the kicker -- rigorous! The buildup of carbon into the EGR is a big problem. It also gunks up the idle air control valve and there's no idle screw -- all ECU controlled. Most are running around rattling teeth at the 450 RPM idle. Replacing the oil filter is a huge pain. The Peterbilt-sized filter barely squeezes through the suspension parts. The recommendation is to remove the right-front wheel to get to it easily. What if you use ramps? This (1995) model year had 7 recalls and terrible wiring. There are some wires to the fans with cracked insulation, exposing bare wire (heat/humidity was the culprit). '96-onward fixed most of the problems.

RH77

[metroschultz]

Most cars have a common power soource for the injector(s).

If you tie into that and kill the power to the injectors you effectively kill the engine immediately with no fuel loss.
It would be the same as if you had pulled the injector connector loose.
I am not sure whether or not it would set a code on your engine, but it won't set a code on the '95 & older Metros.(at least not on mine)
Anyway, just a thought on a different yet similar way to kill the engine for EOC.
TTFN
S.

[RH77]

Originally Posted by metroschultz

I am not sure whether or not it would set a code on your engine

FI cutoff produces something like a misfire code. Easy to reset with the SG.

Still searching for that CEL-free cutoff...

RH77