Car misfiring after changing plugs

JoeySully

hi

Changed the plugs in my car this weekend
1L 90 starlet.
now its misfiring , if thats what you call it it kicks every 20 seconds or so. no loss of power really.
I did not adjust the clearance on the plug, after i hd them in i was told that they should be set but i dont know what it should be. This is the problem i think but what is the correct setting for the plugs and what else could it be?

Wishbone Ash

Did you connect the leads correctly to the plugs?

JoeySully

Wishbone Ash wrote:

Did you connect the leads correctly to the plugs?

yes changed them one by one and replaced each cable after each plug change.

alias no.9

Plugs are usually set right these days. Check that you've replaced all of the leads correctly.

[edit] by correctly I mean that they are fixed onto the plug correctly, I do understand that you did them in order [/edit]

JoeySully

alias no.9 wrote:

Plugs are usually set right these days. Check that you've replaced all of the leads correctly.

[edit] by correctly I mean that they are fixed onto the plug correctly, I do understand that you did them in order [/edit]

yes iv also done that even pushed each one in turn, left and right and held there to make sure that a contact was made and it mad no difference.

could i have got a bad plug?

Henry Ford III

Did you set the gap on the plugs?

JoeySully

Henry Ford III wrote:

Did you set the gap on the plugs?

No I didn't as i didn'yt know the correct setting.

ismynametoolong

Not only could you have a bad plug you could have a counterfit plug .
Crazy as it may seem there has been cases of engine damage caused by counterfit spark plugs . The copies are made in China and have made their way into motor factors here through someone buying a cheap job lot .
The ones i have come accross are NGK. The tips fall off them and they continue to burn destroying the cylinder . I suppose 100,000 spark plugs at 50c each as opposed to the normal €1.20 is a nice little mark until something goes wrong .

MercMad

But you say you get a "kick" every 20 seconds or so ? If you had a plug that was not firing you would get it every second or 2 !

Are the plugs the corrct type ? If you use an insulated pliers you can remove each lead one by one to isolate where the misfiring cylinder, if you are still convinced thats the problem. If you find absolutely which one is causing the problem, then first swap the leads between 2 cylinders, completeley, i.e at both ends ! If the problem moves, you have a faulty lead. If not remove the plug, examine it and ensure you have any gap in it, in fact most Toyotas have a sticker in the engine bay stating the gap !

Did you discover if the car has points in it !

JoeySully

ismynametoolong wrote:

Not only could you have a bad plug you could have a counterfit plug .
Crazy as it may seem there has been cases of engine damage caused by counterfit spark plugs . The copies are made in China and have made their way into motor factors here through someone buying a cheap job lot .
The ones i have come accross are NGK. The tips fall off them and they continue to burn destroying the cylinder . I suppose 100,000 spark plugs at 50c each as opposed to the normal €1.20 is a nice little mark until something goes wrong .

They are NGK. bought in a reputable motor factor at ~4€ a each.

JoeySully

MercMad wrote:

But you say you get a "kick" every 20 seconds or so ? If you had a plug that was not firing you would get it every second or 2 !

Are the plugs the corrct type ? If you use an insulated pliers you can remove each lead one by one to isolate where the misfiring cylinder, if you are still convinced thats the problem. If you find absolutely which one is causing the problem, then first swap the leads between 2 cylinders, completeley, i.e at both ends ! If the problem moves, you have a faulty lead. If not remove the plug, examine it and ensure you have any gap in it, in fact most Toyotas have a sticker in the engine bay stating the gap !

Did you discover if the car has points in it !

Great idea. plugs are i believe are correct however the clearance may not be set correctly. Looked for that sticker but couldnt find any info on plug clearance.

Alun

Possibly you might also have one or more knackered plug leads which only showed after they were moved about to replace the plugs.

JoeySully

Alun wrote:

Possibly you might also have one or more knackered plug leads which only showed after they were moved about to replace the plugs.

Looks like there are too may variables in this equation. think ill try swapping the new plusgs one by on with an old one. if result is the same then do leads one by one.

MercMad wrote:

Did you discover if the car has points in it !

Yes i found the points . gace the rotor a good cleaning till it was shiny again and cleaned dis cap.

Well there is another question. is it worth while changing a distributer cap??

MercMad

Its worthwile ensuring you didn't disturb something like the rotor, points wire, ensure the cap is sitting on the dizzie correctly. How did you clean the points ? Did you remove them ?

JoeySully

MercMad wrote:

Its worthwile ensuring you didn't disturb something like the rotor, points wire, ensure the cap is sitting on the dizzie correctly. How did you clean the points ? Did you remove them ?

I did not clean the Points just distrib cap metal contacts and the metal on the rotor(im guessing that dizzie means rotor or have i got the incorrect name for it) it made no difference afer i did it anyway so the problem is 99% sure, not in the distributer cap.

Audioslaven

Hi,

This happen me before in a Nissan almera but i was losing power. I used to drop them down and then put down the spanner and tighten them.

Take them all up again and put the back down again(fix the plug in the spanner and put them in gently). Probably one of them is not fully in !!

crosstownk

This is quite common on VWs, Seats etc - the plug leads sometimes get damaged by accident when you're removing them. I'm not sying that this is your problem but it'd be worth checking by removing each plug lead one at a time and seeing if the fault persists.