LFX experiencing run-on every now and then
 

Anyone else having any issues with the engine staying running while the car is shut off? Trying to track this down on my LFX.

It isn't happening all of the time, but some nights when I park in my driveway, I'll have the car in 1st, clutch pressed in, apply the parking brake, turn the engine off, remove the key from the ignition, and it's still sputtering and running. If I clutch out the car stalls, and if I keep holding the clutch in, it eventually sputters out and dies.

try changing gas brand/octane first and see what she does before starting anything else

I'm tuned with 93 octane sunoco in the car, and only ever use 93 Sunoco.

have you made any changes lately before it started? spark plugs? CAI? exhaust? fuel system cleaner?

Negative. Have had no changes made recently. It's done this once before for 2 days (roughly 2 months ago), and then went away. Last night it did it again.

Last time this happened, I checked all of the sensors, and cleaned the MAF. This weekend I'll pull a plug or 2 and take a look at those.

Just curious if anyone else has experienced this with the LFX before.

Other notes, oil level is good, car has a catch-can and has had it for its whole life, 62,000 miles.

i would start by changing gas stations and checking for vacuum leaks and pulling the spark plugs to see what they look like. Wont cost you a dime and only about an hour of your time

A fuel injected car with run on? I can't say I've heard of that. Must be burning oil, because it should quit delivering fuel the second you turn the key off. Maybe it's indicative of an injector that doesn't close all the way or something. I've never heard of anything like that - I'd be interested to learn what you find.

I know, it blew my mind the first time it happened. I was holding the key in my hand, and stalled my car.

Uh. Well. Do you have an OBD2 module? You might have a code to go off of even if the CEL isn't on. That, or if you had some way of looking at the car's data while it's running / shutting off that would help a lot. Like acammer said, sounds like a fuel issue, injector or otherwise. Also sounds like the inverse of an issue I had a few months ago where I started my car and it started sputtering almost immediately and threw a TPS / MAF correlation error CEL. It actually did that a total of 3 times over like 30 days. Hasn't done it since though.

Leaking injectors can give you the dieseling experience. Rare but it's happened.

I do have HPTuners and can run scans. Naturally it hasn't done it since I started this thread and hooked my HPT to it.

Check the fuel pressure regulator.

the V6 cars have a fuel pressure regulator?

Bad ignition switch? If the switch is good than something is igniting the fuel, likely carbon deposits. Suggest getting a boroscope and pulling each plug and taking a look inside. But, yes like someone else said, this shouldn't happen with fuel injected vehicles since the fuel supply should be cut off with the ignition switch. If fuel is leaking from injectors, then that could be part of this as well. Perhaps let it sit overnight and then pull each plug and see if you smell gas more than others, which might be a leaking injector.