Engine wont shut off
 

So... interesting predicament here. We're prepping a buddy's car for Aircare and since we couldn't tune Megasquirt properly to pass the emissions portion, we decided to strip all the turbo and MS parts and bring it all back to stock. The only thing that's not back to stock at the moment is a relocated battery.

Tonight, however, we came across an issue. When you turn the key to the off position, the engine should die... right? Well, tonight the engine kept running despite the fact that the keys were sitting out of the ignition and on top of the seat. It only died after we pulled power to the main relay. This has kinda cropped up in the past, but the engine would only keep running for a second or two before dying. And even that was only infrequent enough that we were focused on other issues instead of trying to figure it out. We associated it with part of the MS harness that was going to be replaced anyway. However, we're back to the stock harness, so that can be ruled out.

Any thoughts as to what might be causing this issue? Perhaps a faulty ignition relay or even the cylinder itself?

does he have keyless entry/ remote start ?

How about telling us what car it is and what mods the car has?
Stock alarm?

We need more details.

is the timing really really advanced?

From the sounds of it, the car is fuel injected, so the advanced timing should not cause the engine to continue to run with the ignition off.

Basically, there is something wired wrong and is giving a constant power source to the ecu and fuel pump.

I know of a US import S2000 where the parking lights was wired to the ignition as a cheap DRL. Well, as long as the lights were on, the motor would stay running with the ignition off.

In this case, was the alarm wired incorrectly? Turbo timer wired incorrectly?

Again, more details please.

It's a '93 Ford Probe with a momentarily stock '94 KLDE engine.

No keyless anything, no remote start, and no alarm. The car is currently back to 99% stock form. The only mods on the car right now are about three Autometer gauges w/corresponding sensors plugged into the engine, and the battery relocated into the truck with a kill switch wired in. All of the Megasquirt and turbo parts are off the car right now.

The timing is actually advanced about as far as the disty would allow. It's running pig rich and wont start unless it's in it's current position. That's another issue that we're fixing, but didn't get to before we decided to call it a night.

Edit: Just remembered that the fuel pump is currently wired in as constantly "on" through the diagnostic box. Don't think that would be an issue as it's been like that all week and it's never been a problem.

maybe try retarding the timing and see if it helps? maybe start the car and turn the dist. back while its running. i had the same problem with a golf, the timing was advanced (the gear was 1 tooth off after they did the timing belt) and after i fixed it the problem was ALMOST gone. i decarbonized the engine after that and the problem went away completely

Can it be as simple as your ignition switch?.. I am currently fighting the steering column of a e36 to get to a similar issue.

Its possible your ignition switch isnt shunting to ground when turned off