miss

[maxpaine]

what can be making a missfiring on a nova 1.3 sr with all newm sparks everthing, exepte the sparcks cables.
One more question what is the missfiring

[doni_nova12]

the cables lol

[maxpaine]

nobody else

[ade]

A misfire is where the engine skips a beat - ie one of the cylinders does not spark, does not ignite the fuel/air mix and it doesnt force the piston back down causing the engine to judder and sound terrible...

To create a misfire just remove an HT lead (make sure the engines off before hand coz you may get a shock)

there could be several reasons why a car misfires...

1. blown head gasket
2. HT leads or firing order wrong
3. duff spark plug/ht lead
4. spark plug not connected to ht leads right
5. timing out
6. incorrect spoark plug gap
7. low compression/piston damage other internat damage
8. HT leads connected to dizzy cap wrong
9. Dizzy cap cracked, damaged or skipping
etc...

was the misfire occuring before you changed the plugs?

If not then its a plug/HT lead firing order issue. Did you note which HT lead went to which plug and which end connected to which plug on the dizzy cap?

I think youve put the HT leads on wrong and got the firing order mixed up.

Its usually 1324 (I think) - check Haynes for details...

Ade
:wink:

[Adam]

Its usually 1324 (I think) - check Haynes for details...

Close :wink: , its 1342 (I think( in an anticlokwise direction on the cap.

[maxpaine]

already done that only didnt chage the spark cables. i already done that and i already chaged the head gasket it was all fine engine pistons and everthing could be the dizzy ?

[ade]

already done what mate?

So - youve changed everything except cables but its still misfiring (I presume when you say cables you mean HT leads)?

Change cables?

:roll:

If its not that then yeah change dizzy cap or rotor arm.

To check if dizzy knackered -

1st locate which cylinder is misfiring - to do this remove each lead from the spark plug in turn - the knackered one wont affect engine when removed...

Then with that HT lead removed from spark plug, stick it on the engine block and see if it sparks - if it does then the dizzy is fine (spark getting to plug) - which means its either a spark plug issue (change plug) or engine fault (get compression test done - this should have been done already if head gasket changed)

If theres no spark then change dizzy/rotor arm.

If head gasket was changed and after changing dizzy/rotor arm its still misfiring I'd return it back to garage and get then to check compression on faulty cylinder, look at timing etc...

Is it smoking at the back?

Could be summut like a bent valve, piston rings etc...

[ade]

did you change head gasket yourself?

If so I presume you knew what you were doing and skimmed the head?

(if you did it yourself I;m surprised you dont know what misfiring is)

:?

[maxpaine]

yes i did it
it was whit a mecanic :P

[maxpaine]

its not smoking and the compression its hight 1:11 :P but its equal in all

[ade]

then I'd check for spark from HT leads on cylinder thats misfiring and if no spark change lead, then dizzy/rotor arm.

Ade

[maxpaine]

gracias