One cylinder running cooler

[ukkid35]

What should I check, swap, or change to resolve this?

[oakdale]

First thing I'd do would be to buy some decent spark plugs.

[stevieturbo]

nothing in old used plugs indicates hotter or cooler.

Perhaps one is running a little richer than the others there, or has weaker ignition for whatever reason.

whether that's just at idle, or any other time is impossible to say from those plugs.

[oakdale]

Seriously, I'd ditch those plugs, Unipart are a long defunct motor factor who didn't make plugs, they just rebranded someone else's stuff.

In about 2006 they started repackaging NGK plugs but the ones you have look like Champion ones and must have been made about 20 years ago or more, I don't know what champion plugs are like now but they were crap then.

I was in the trade during that period and wouldn't touch them with a bargepole.

[stevieturbo]

oakdale said:

Seriously, I'd ditch those plugs, Unipart are a long defunct motor factor who didn't make plugs, they just rebranded someone else's stuff.

In about 2006 they started repackaging NGK plugs but the ones you have look like Champion ones and must have been made about 20 years ago or more, I don't know what champion plugs are like now but they were crap then.

I was in the trade during that period and wouldn't touch them with a bargepole.

Yep

[ukkid35]

oakdale said:

In about 2006 they started repackaging NGK plugs but the ones you have look like Champion ones and must have been made about 20 years ago or more, I don't know what champion plugs are like now but they were crap then.

I was in the trade during that period and wouldn't touch them with a bargepole.

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

[E-bmw]

Champion just aren't a good plug.

The only plugs to use are NGK, always have been.

When fitted, give them a good run & if you think there could be an issue pull them when warm & check again.

[julianm]

You might not like Champion plugs, but their history is quite a story - http://www.mycitymag.com/a-spark-of-brilliance-the...

[oakdale]

ukkid35 said:

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

Many were faulty from new, if you serviced a car and fitted Champion plugs, the car would often have a misfire it didn't have before.

[stevieturbo]

ukkid35 said:

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

Regardless of Champions history, I've never considered them good plugs. NGK or Denso for me

And what makes you think those plugs are brand new ? They look very old

[E-bmw]

stevieturbo said:

ukkid35 said:

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

Regardless of Champions history, I've never considered them good plugs. NGK or Denso for me

And what makes you think those plugs are brand new ? They look very old

He said those ones have been binned & replaced with new the same.

[Tony1963]

OP,

When a product has a reputation for poor quality, quite often one factor that suffers is manufacturing consistency/tolerances. So seven plugs could be ‘ok’ but one could be outside of what NGK says is acceptable, for example. So that one plug might be running at the wrong temperature.

[AW111]

oakdale said:

ukkid35 said:

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

Many were faulty from new, if you serviced a car and fitted Champion plugs, the car would often have a misfire it didn't have before.

I spent a lot of time (and some money) chasing a high rpm miss in my first modified car.

Then someone more experienced than me told me to bin the Champions and fit a spark plug that worked (NGK).

I did so, and the engine finally could actually rev past 6,500.

[SystemOfAFrown]

I share the general disdain for Champion plugs, but have you actually noticed the engine misfiring? I might be inclined to get the injectors tested, a leaking/dribbling injector can do exactly this.

[ukkid35]

SystemOfAFrown said:

I share the general disdain for Champion plugs, but have you actually noticed the engine misfiring? I might be inclined to get the injectors tested, a leaking/dribbling injector can do exactly this.

Thanks, they were tested/cleaned, but not too recently

I will swap the injector and plug lead, to different cylinders, if the new (old stock) plugs show the same colour pattern

I will also replace with NGK in due course

Gratuitous photo included

[ukkid35]

oakdale said:

Seriously, I'd ditch those plugs, Unipart are a long defunct motor factor who didn't make plugs, they just rebranded someone else's stuff.

In about 2006 they started repackaging NGK plugs but the ones you have look like Champion ones and must have been made about 20 years ago or more, I don't know what champion plugs are like now but they were crap then.

I was in the trade during that period and wouldn't touch them with a bargepole.

You were so right

The new plugs (albeit Unipart old stock) fixed the issue quite dramatically

The car is running wonderfully now at low revs, not used to that

Thanks for for your great advice

[catman]

oakdale said:

ukkid35 said:

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

Many were faulty from new, if you serviced a car and fitted Champion plugs, the car would often have a misfire it didn't have before.

I know of someone from years ago, had a Triumph Vitesse with a misfire. Replaced the old plugs with 6 new Champions, car still misfiring. New Points, rotor arm, condenser, leads, coil. Still misfiring. Cylinder head off, nothing wrong there. Gives up, puts it into his local garage and gets a call shortly after to say that it's running fine. Two of the new Champions were duff.

[lemonslap]

catman said:

oakdale said:

ukkid35 said:

I didn't realise there was a problem with Champion plugs

I will change them for NGK, but is there a reason why brand new plugs would fail instantly?

Also, what is the critical failure mode for Champion of that era (assuming they are 20 years old)

The ones in the photo have been binned, but replaced with a 'new old stock' set of the same

Many were faulty from new, if you serviced a car and fitted Champion plugs, the car would often have a misfire it didn't have before.

I know of someone from years ago, had a Triumph Vitesse with a misfire. Replaced the old plugs with 6 new Champions, car still misfiring. New Points, rotor arm, condenser, leads, coil. Still misfiring. Cylinder head off, nothing wrong there. Gives up, puts it into his local garage and gets a call shortly after to say that it's running fine. Two of the new Champions were duff.

Reminds me of chasing a misfire 25 years ago on my old fiesta, again champion plugs. Much scratching of heads amd it turned out the insulator on the spark plug was detached and slid down over the electrode, but of course this was only visible when the plug was pointing downwards as when you turned the plug up to inspect the insulator it would slide back to the correct position!

[ukkid35]

Have just removed the new old stock Unipart plugs after completing a track day at Spa, they all looked similar, may post a pic later

The car was running rough again, but now with new NGKs it is much smoother

Wonder how long that will last

[oakdale]

ukkid35 said:

Have just removed the new old stock Unipart plugs after completing a track day at Spa, they all looked similar, may post a pic later

The car was running rough again, but now with new NGKs it is much smoother

Wonder how long that will last

You've done the right thing at last , I'm sure it will be fine now.