Why does my engine keep running after i turn it off?! help needed.
 

I have an S5 and im having a pretty big problem.. For some odd reason the car keeps running even after i turn the key back to off...

I have a turbo timer and through process of elimination ive already ruled it out...

I dont know what it is or what to look for... If i start the car (engine and all) then go to turn it off it the motor keeps running and i dont understand why...


But when i turn the key to on without starting the engine, all the power shuts down once i turn the ignition switch off... !!!???

I have also noticed that you can hear the relays in the car switch off but they do it in a delayed manner.. and when the engine is running the dont switch off at all...

IM LOST CONFUSED AND FRUSTRATED SOMEONE PLEASE HELP...

Thank You,

if i had to guess.............your turbo timer is not wired in properly. either that, or you blew a fuse somewhere in the wiring circuit to the turbo timer

Clean the emission harness ground for starters. When I had no motor in, and turned the key off, the only way the main relay would turn off is if I grounded the engine harness.

Its worth a try.

@blackrotary - I uninstalled the turbo timer completely and put everything together in stock form.. it still did it...

@nate - funny you said that because when i put the motor in i grounded the ground that went to the starter in a whole different spot not the spot it was meant to be grounded on.. Is that what you are referring to?

Main Relay could be stuck in the "relay" position and not shutting power off to the ECU among other things. You could try disconnecting the two wire plug from the relay while the car runs but key to off to see if it shuts the engine off or not, and if not, then disconnect the four wire plug to the relay and see what happens.

well the thing is that i dont have a stock ECU i havea MICROTECH LT10s on the car.. Does that change things?

It shouldn't.

well, i would double check the wiring since you uninstalled the turbo timer. you never know, you might have crossed something somewhere. it sounds to me like there might be a power wire connected to a signal wire somewhere. power to power, signal to signal, ground to ground. see what i am saying? if you have a signal wire connected to a power wire, you have constant power to a wire that is only supposed to see signal which would SIGNAL whatever it is connected to to stay on.

usually this is the result from wiring a thermo fan without a relay

@satch - im going to try to unplug the main harness like you said today.

@balckroatry - and i will go ahead and double check the wiring harness under the dash... Is there a wiring diagram here on the forum that shows me what plugs have power and what not?

@bumpstart - I have a fan but its connected to a relay..... ???

That's the "Main Relay," and it needs to be disconnected in the order stated (two wire plug first). Also, if you have an S4 alternator, if the Black/White wire grounds against anything metal it will cause the car to not turn off.

Ill do it in the order you stated. And that black/white wire isnt grounding out i made sure of that.

And just to let you guys know there are no Black/White wires on my alternator plug. One is white with a blue stripe and the other is black with a white stripe...??

Black/White means a Black wire with a White stripe.