High mileage missfire (non clio)

[guysy]

I wasnt sure where to put this, the car isnt a clio is a honda civic 1.6 on 128k miles.

Its my girlfriends mum's and she use it a few times a week, being a honda it runs well still, its been serviced on and off by a friend mechanic of hers but tbh i wouldnt say its been treated like a baby car.

I was told the car had an engine diagnostics light on so i used my cheap diagnostics obd2 reader.

And had the following codes:

Misfire cylinder 3
Misfire cylinder 4
random/multiple misfire

the pending fault was: Misfire cylinder 4. Does pending mean the current ?

She's not looking to spend any money on the car that she can help, and i know from research the misfire could be the distributor? Because ive said for the sake of 12 quid i would change the spark plugs for her and hope that helped.

My question is: I've always thoughts changing one part of something thats old (i.e. plugs) could then put more pressure on the ignition leads and distributor afterwards? is that right to think so in general?

Im thinking if i go and change the plugs it might kill off other parts that where just limping along. The car now doesnt seem to be misfiring so i'm wondering weather to leave it or just change the plugs and it will be fine.

Thoughts please?

 

[guysy]

Anyone have any opinions?

 

[Bluebeard]

Unless you know someone with the same car (and can chop and change parts) then the cheapest way of fixing this is to replace cheapest bits first.

Personally, I'd pay someone with proper equipment to diagnose it.

Not some mickey mouse code reader.

 

[ross0530]

its the old parts that put more strain on the rest, for example the worn spark plugs put alot more strain on leads, dizzy and most of all the coil. etc

 

[guysy]

Cheers for the reply's, Daniel i agree but this isn't likely to happen, as long as the car moves it wont have any unneeded attention because its just a runner.

Ive found the obd2 code reader fairly accurate in the past? not very good overall then?

And i don't have another car to switch parts from. Cheers ross understood now, I think ill just change the plugs over there only £12 and easy to do.

 

[Bluebeard]

I'd start with plugs, then leads.

Honda's very very rarely go wrong so I would put money on it being a servicable item thats failed.

 

[guysy]

Cheers Daniel at the mileage its on I think the plugs need changing anyway, so ill go through the motions.

 

[Russ_16v]

Id do plugs, leads, dizzy cap and rotor arm - will be under £50 for the lot, and the main part of the ignition system will be fine - id guess it is one of these, could be any or all

 

[guysy]

Cheers Russ, ill have a look into the rest and see about replacing them

 

[MicKPM]

Check the snap shot information before clearing down the codes... This info can help when using ODB readers.

From above it appears the problem is down to cylinders 3 & 4 so if it's a waste spark ignition, unless it's got a lead issue, it rules out an ignition fault. Next step would be to confirm injection is all good and then check the basic engine health (compression test and leak down test).