AWolf

I have been having a fair amont of dieseling when I turn the car off lately. Should this be something I worry about? It seems to do it a little more when the car has warmed up. I turn the key all the way off and the car sputters like its trying to start again then shuts off. If it is not harming my car then It does not really bother me. Thanks for the help.
-Andrew

L8 APEKS

Could be something as simple as timing being too far off...or something worse. Hard to say. I wish I were more familiar with "typical' 944 issues, but double checking your ign timing is a cheap and quick thing to check.

Zero10

Umm, the timing is electronic.
Sorry

If it's dieseling that's a little strange. The coil is turned off as soon as the ignition is off. The fuel injectors SHOULD stop firing. However, maybe it's a leaky injector or something?
Although, I can't understand why there would be ignition.

L8 APEKS

...so no 944 has ever had any sort of problem with the ignition system before? Wow! That's hard to believe!

Just trying to help.

Micah

Has this problem been exacerbated by colder weather?

Micah

inactiveuser92616

could be excessive carbon deposits combined with a leaky injector. Some fuel system cleaner may treat the symptoms, but the cause is likely still there.

Zero10

Wow, I was being nice, and then this.
What happened to whoever stopped these guys at the door?

Anyhoo, that said.

Is it actually firing after the car turns off, or is it just taking a long time to stop spinning?
Perhaps we can nail this thing down.

I really hope it's not actually firing, that makes it even stranger.
Really reaching here, but what if you turn it off quickly, or remove the key right away when you turn it off?
Perhaps it's an issue with the ignition switch.

FSAEracer03

This is a long shot really... but if it's running lean and combustion temps elevate, the plugs can keep hot enough to ignite for a few cycles until the fuel cools them down.

Sooo... leaky injector(s) + lean tune = deiseling/stumbling on shutdown

I doubt this is the case, though it might be worth looking into.

AWolf

The car is actually firing a couple of times before it shuts off. I havent checked the timing and it does not seem to be affected by cold temps(I live in san diego so cold is a relative term) It is basically like when I used to drag race we had a camaro, and after really hot runs we would shut off the engine and it would sputter a little then shut off. Hope that helps.

-Andrew

Perry 951

I'd bet you have an injector or two that are dripping some fuel.

Friendan

My beater Oldsmobile diesels like a ****...the timing is screwed and the choke is all twisted and gummed up...but of course it has a carb. It's actually quite funny, I'm often waiting up to a minute for the engine to stop dieseling, then when it's finally done it lets out a big grunt from the engine and then shuts off.
Probably not the best thing for the car though, the pistons are still firing but the rest of the cars functions are not operational because the ignition is off. I'd check that out asap.

L8 APEKS

In case you didn't notice, the "ummm..." preceding your statement, followed by the "Sorry." (read as..."Sorry...you're an idiot"), came off as you trying to be a smart-**** and make me look like an idiot. So I replied as such.

Had I been in your shoes, I would have said something more a kin to:

"Well, the ignition is electronically controlled so that's pretty unlikely...so maybe it could be <insert helpful suggestion here>..."

...that sounds a little bit more like you are genuinely trying to help others learn. As opposed to sounding like a pompous a$$.

I am very friendly, but I have little patience for forum trolls - if I misunderstood your choice of words, I'm sorry...but it doesn't take a rocket scientist to see you were at least somewhat trying to put me down.

That is all. Carry on. Live long and prosper. ...and all that jazz.

AWolf

It is always fun to have a thread where people argue. Makes you feel kind of important. So what I am hearing from people is that It is most likely a timing or injector issue and that I sould start with a fuel system flush? I really do appreciate the help on this guys.
-Andrew

FSAEracer03

Fuel system flush sounds like a good start... you might try checking out, or having the injectors checked out by a Porsche specialist or respectable shop. Do you have another car to take them over in?

AWolf

Yes, my Porsche is not my daily driver so I could definately take out the injectors and have them looked at. Just for refrence what do Injectors cost for our cars?
-Andrew