Engine runs on after key is turned off.

hello. I have just recently brought a Nissan patrol gu 1999 st 4.2l diesel. I have seen 2 different mechanics and been told different things. the engine runs on after keys turned off. petrol it would be timing but diesel I don't know. I have some knowledge of petrol engines but as this is my first diesel and first 4x4 I don't know a lot. (still learning). so I think they were trying to take advantage of that and make me spend big bucks when only a small problem. if someone could help with this would be much appreciated. Thanks Aaron.

It could be the fuel shut off solenoid. When you turn the key off that solenoid should stop any fuel coming through but it sounds like it might not be shutting properly and letting some fuel through.

Hi Aaron an intro would be the right way before asking for advice just something the forum asks of us all.
sure someone will have an answer for you soon though

sorry. first time user. what do u mean intro? im a Capricorn and I like long walks on the beach. haha just laughs. i'll keep in mind. cheers

thanks mate, sounds good my mate said same thing but wasn't 100% sure. is it easy to do myself or should I take to mechanic? im fairly mechanical minded, I do all my own servicing myself ect.

Just tap on forum header and you'll see introductions ,
just like a hand shake no harm done, tell us a bit about yourself and your Patrol

intro's up. cheers

G'day Aaron, interested to see what answers you might get here, mine runs on once a month maybe and it runs rough when it does it.
Always thought the fuel solenoid has not completely shut off. Be good to know what it is.

PS don't sweat too much about the intro thing, some get all wound up about it, me I hardly read them and don't care if you have an intro or not.
The responses you will get are mostly cut and paste same old same old that just fill up the thread anyway.
But you say you have done so, now you will be left alone. Welcome any way.

Like Macca mine runs on every now and then for a second or so. Normally after a longish run, I let it idle for 10-15 seconds and it doesn't happen, when I haven't let it idle is when it happens.
The "intro thing" is something we ask for as we do have a good mob here, like saying gday when you meet someone I spose. I don't cut n paste for the record and normally use the persons name when replying. Maccas right a lot of people don't read the intros. My favourite colours blue, but im colour blind so it could be bloody anything :)

how long does it keep running for?

Aaron,

My old 4.2 used to do it every now and again too.

Never harmed it at all, as it still ran like clockwork when I sold it.

I would add that it is the fuel solenoid too - If it bothers you too much, then take a look at the wiring first to make sure that the terminations are good, and if there doesn't seem to be a damage or corrosion, then take a look at the solenoid itself.

Mic

Quote:

---

Originally Posted by growler2058

I let it idle for 10-15 seconds and it doesn't happen, when I haven't let it idle is when it happens.

---

I will give that a go, thanks for the tip.

Its just that you can't stop a Nissan with a TD4.2. But seriously, mine dose it also. Have given up on finding the coarse. It doesn't do it all the time but when it dose, I just floor the go pedal with the key turned off. Stops strait away then.

This is very common for the 4.2's. The problem is initially caused by lack of maintenance. But once the damage is done there is nothing you can do about it but change the solenoid. If you dont change you fuel filter often enough the fuel pump has to work alot harder to pump fuel and becomes very hot hardening the small piece of rubber on the bottom of the solenoid. This is also the major cause of leaks as the o-rings are affected the same way.

There is a rare chance the pump is just worn out but there are many other symptoms that go along with that.

Hi MikeBossyBos, sometimes only for a few seconds but sometimes maybe 5 seconds feels like forever and she sounds rough when its happening. she runs beautiful & don't want to hurt her.

thank you every body for your help its been great to hear everyone's thoughts. I have really enjoyed this forum. good crowd. cheers.

I have noticed that mine seems to run on much more on the hotter days.