Shaking of excess fuel/ air mixture after ignition is turned off.

[79estate]

HAe Fellas,

Just wanting to know,

When i have turned my ignition off, it seems to shake and keep igniting excess fuel and air mixture in the combustion chamber, so shakes for a couple of seconds??

Is this bad for engine??

I have been told Timing might be slightly out of kilture, IS this correct??
As shakes everytime time after ignition is turned off.

Cheers Mikey.

[kierbear]

lol this happens to me sometimes and the guy at the gas station said "your car sounds like shit", and so i said "when was the last time u even seen an avenger?" at which he seemed stumped so i said "that's what i thought, its a fucking miracle its running at all tbh" and havnt been back since. blacklist= havelock north mobil

[JoKer]

carbon build up?

[hunted]

could be a number of things.

Check the timing, if its too advanced it will be causing it to run hot and will overrun (which is what you are experieincing)

Also, try using 95 (assuming you are using 91 petrol).

I had the same issue with my avenger and tried everything but to no avail, then as soon as I started using 95 petrol it instantly stopped.

[hunted]

also just to clarify, excess fuel/air isnt the main issue, as it needs an ignition source to actually burn. Normally you could just cut ignition and the motor will stop.

what causes overrun is the combustion chamber being so hot that it can ignite the fuel/air mixture without any spark.

timing to far advanced is an obvious cause, so like I said, check that. (cant remember what an avenger should be, but probably around 10-15).

If that doesnt work, try going through a couple of tanks of 95, you may be surprised. Like I said above, this ended up solving the same problem for me.

I assume you are in auckland (lol) if you were in wellington Id offer to come have a nosey

[oldschool]

Nothing to do with the timing...advanced timing actually makes your engine run cooler, it will just pink if too advanced.
Retarded timing makes your engine produce less power, so you have to put your foot down more, causing it to run hotter...if your cooling system is suspect.
Nothing to do with carbon build up either as 1970's+ engines, along with modern fuels and oils are designed to minimise carbon build up.
The main causes of 'running on' are...
1/ Idling too fast (particularly autos)
2/ Engine running hot (faulty cooling system)
3/ Wrong petrol (octane too low)
4/ Wrong spark plugs (too hot)
5/ Mixture too rich