2001 Jaguar S Type 3.0 v6. It will not shut off, then wouldn't start.. I have replace the ignition switch. Now vehicle starts but doesn't shut off not even after removing the keys completely and unhooking both power and ground terminals. I had to disconnect the sensor on air filter to get car to stop running... anyone figure or have this issue figured on it

 

Have a look through this lot, there may be something applicable.

(1) how to stop a car dieseling - Search (bing.com)

 

Just to be clear. When you say it won’t shut off:
Do you mean the engine runs as normal and can be revved and returns to idle even though the ignition is turned off?
Or do you mean the engine runs lumpily for a minute or so before dying after ignition is turned off? (Running-on or ‘dieseling’)

Both have completely different characteristics and causes, so it is necessary to distinguish which.

 

Ooh, excellent point. I hadn’t considered dieseling.

Also, please clarify the sequence of events before and after replacing the ignition switch. It’s not very clear. Is this the correct order?:

Engine would not start.*

Replaced ign switch.

Engine now starts.

New problem: Engine will not shut off.


We’re not trying to nitpick you. We just want to make sure we have all the clues.

IIRC, the ignition switch controls several relays which in turn control the power for fuel and spark. I’d have to dig a bit deeper to see how to test if these relays are receiving the correct commands and responding properly.

*No start - more details here too, please. Did the starter engage normally and get the crankshaft spinning at a good clip, even if the engine would not run on its own? Or was the starter sluggish? Or maybe no response, or just a clunk or buzz?

 

+1 on knowing more details and full description of the issue.

Letting the engine run with the battery leads disconnected is going to damage the alternator.