Spark plug leads

**wynode** · 12-03-2005 09:48 AM

Whats the best way to test them apart from visual inspection?

I attacked mine with a multimeter today and noted the following ressistances.

Cyl# Ressistance (Ohms)
1 10.75
2 10.20
3 7.81
4 6.70

Time to change the leads? (they've been on there for AGES!)

**Macros** · 12-03-2005 10:17 AM

yup

**Weq** · 12-03-2005 10:25 AM

ive got a set of honda leads

hit me up

**wynode** · 12-03-2005 07:30 PM

LOL@Weq

I was wondering what the values should be roughly. I'm assuming the difference in values is because cylinder #1 is the furthest away and #4 the closest to the dizzy. ?

**ECU-MAN** · 12-03-2005 11:07 PM

yep the longer the lead the higher the resistence.

your leads are still with in spec, posibly the high side, but not bad

**wynode** · 13-03-2005 10:04 PM

Do you know what propper spec is John?

**ECU-MAN** · 14-03-2005 10:40 PM

cant remember off the top of my head, but somthing like 10ohm per foot max, I think

**mastcell** · 10-06-2007 11:50 PM

Sorry for bringing up old post, I have a question:

When one lead is worn out, should I change just that one or change all four of them at the same time?

**yourfather** · 10-06-2007 11:53 PM

you're probably better off doing all 4 at once, otherwise maintenance down the track will be, oh dont replace number 2 cuz I did that 2 months ago, and your mechanic will stuff up, etc etc.

Just do it once, take the hit.

Plus, it's a EURO, so make sure you do the best you can to keep it in good condition.

**dsp26** · 11-06-2007 12:08 AM

Originally Posted by wynode

LOL@Weq

I was wondering what the values should be roughly. I'm assuming the difference in values is because cylinder #1 is the furthest away and #4 the closest to the dizzy. ?

yup but newish is less than 2500ohm per foot.... cyl1 lead is about 1 foot

***EDIT***
farking lol... holy thread revival! i quoted someone who knows the answer by now.

well at least it's good to know people still search

but yeah better off getting them all done... or you can bring your multimeter with you to Pick n Payless lol. thats what i did for the mrs celica when i screwed cyl1 lead

***EDIT AGAIN***
zomg.... my answer about Pick n Payless is irrelevant as they wouldn;t have euros. just do as above and change them all as i don't think you can buy them individually anyway... unless the individual blue Top Gun ones Autobarn sell are universal?

having 1 cylinder not igniting optimally will screw fuel efficiency and performance.

**wynode** · 11-06-2007 12:20 AM

Just get the whole lot done and replace with brand new is my suggestion.

Also a good reading with a multimeter won't always be accurate because the electric stress on the insulation at higher operating voltages will be greater and might not show when you apply only a few volts across it. You really need to do hi-potential testing of the leads to see if there is any leakage current. But that's probably taking it a bit too far

Anyone know what the operating voltage is?

PS: THumbs up for searching mastcell!!!