Mi Misfiring Occasionally And Keeps Running When I Turn It Off!

[PsychoSimon 0]

hi guys.

i went for a drive with batoutofhell just before christmas and the earth wire that goes to the fuel rail burned out (it wore through and contacted the back of the alternator) which killed everything.

I replaced the wire and all was good - or so i thought.

basically every now and again the car will missfire (like its being turned off and on again v.quickly casuing the car to judder). it did this about 3 or four times in 15 miles.

also a few times when i have tried to start it, its been quite hard to start, and when i go to turn it off it keeps running and judders to a halt after a couple of seconds.

 

my thoughts are coil due to the bad starting and the juddering, but the over-running has got me stumped.

Any ideas before i lose faith in my pride and joy?

Cheers,

Simon

 

*EDIT* i am running an 8v coil if that makes any difference?

Edited January 1, 2006 by PsychoSimon

[C_W 3 1 Cars]

My car had similar ignition cut out problems when one of the relays in the loom was intermittantly breaking (think it was the brown one).

[PsychoSimon 0]

do you mean the one of the two that are together? with the 2 pin plug with them also?

*runs out to the garage to check relays*

 

cheers mate, hopefuly its that simple!

Simon

[C_W 3 1 Cars]

Yes one of those two, but not sure why it would be running on.

 

It could somehow be that the coil is constantly live and its only the fuel supply that is being cut when you turn the ignition key off, therefore there is a slight run-on with excess petrol in the head from the injectors/rail???

[PsychoSimon 0]

i checked the relays and replaced then with new ones and still no avail. also have had the multimeter on the coil and the switched live is fine too. y dad seems to think its the coil on its was out and it's holdin a short amount of power in it?

[taylorspug 7]

Running on can be caused by excess carbon deposits in the head igniting when the ignition is turned off (and they are still hot). This doesnt help with the misfire problem, but its another thing to think about...

[PsychoSimon 0]

ok have just changed the amp unit and coil for brand new replacements, and still the same problems.

in regards to the carbon, it only started doing it since i burned the wireout last wekend? could be coincidence but hopefully its not this

Regards,

Simon

[d-9 0]

Sounds like a wiring fault. Check the ignition relay on the mi16 injection loom clicks on and off when you turn the key on/off.

[Longun 1]

Could it be the earth? If it was replaced is it the same size cable? Not sure why it would cause run on tho. Follow the wires path and see where it goes. There could be another point thats burn out because of the short?

[d-9 0]

On reflection its coz the melting earth caused some other wires in the loom to melt together

[PsychoSimon 0]

"On reflection its coz the melting earth caused some other wires in the loom to melt together"

 

I thought this but as it only melted the short piece (it's from the smaal brown connector by the inlet manifold, which also houses the injector wires and starter feed wire etc) i didnt think any permanent lives went through there?

 

Will check it anyway.

Keep the ideas coming anyway guys your helping me out loads here,

Many thanks,

Simon

 

 

*EDIT*

one thing i think i noticed today as well,

when i turned the ignition before, i could here the fuel pump kicking in, now i cant? although it's obviously kicking in when its cranking otherwise it wouldnt run? Is this just my imagination?

Edited January 4, 2006 by PsychoSimon