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[SteveAvfc.]

Hi OOFers can some one shed light as to why my recently fitted VX spark plugs are looking sooted they have only been in for about two months. The car seems to run perfect for a few weeks then starts to play up poor acceleration hunting ect, have recently found breather pipes were cracked so replaced and all seemed well. Then started to run poor again had a look at the plugs and they are sooted at the bases, could this be the problem and if so what would be the best solution. Thanks in advance for your answers.Steve 

[feeutfo]

Do you mean soot on the electrode and insulation from poor combustion?

Or around the external section that sits in the plug well?

[SteveAvfc.]

Do you mean soot on the electrode and insulation from poor combustion?

Or around the external section that sits in the plug well?

The actual electrode tip looks ok-ish but they are sooted around the base and i would say up to three/four thread turns from the base. Externally they are clean. 

[RobG]

Plugs all tightened to 25Nm

[SteveAvfc.]

Plugs all tightened to 25Nm

They were done at the garage Rob so would hope so but who knows ?? Could it be running to rich? if so remedy's please they do look in a poor state for two months wear.

[RobG]

Normal cause of soot is loose plugs, have you checked for tightness. 25Nm will compress the "crush" washer but plugs have and do work loose

[SteveAvfc.]

Normal cause of soot is loose plugs, have you checked for tightness. 25Nm will compress the "crush" washer but plugs have and do work loose

Thanks Rob will look into it 

[feeutfo]

Plugs are coming loose by the sound of it. As Rob says, 25nm each. And as master says, then go over them again as they may well relax on the crush washers.

[Kevin Wood]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

[SteveAvfc.]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

The car seems to run worse during warm up, dose not seem to affect acceleration up through the box its becomes apparent when moving at lower speeds.

[RobG]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

The car seems to run worse during warm up, dose not seem to affect acceleration up through the box its becomes apparent when moving at lower speeds.

[JamesV6CDX]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

The car seems to run worse during warm up, dose not seem to affect acceleration up through the box its becomes apparent when moving at lower speeds.

If I get Claires car done on Saturday in good time I'd be happy to take a look...

[SteveAvfc.]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

The car seems to run worse during warm up, dose not seem to affect acceleration up through the box its becomes apparent when moving at lower speeds.

If I get Claires car done on Saturday in good time I'd be happy to take a look...

Thanks James for your offer will try tightening them first possibly tomorrow afternoon see how it goes. If she still plays up will make contact, your doing Claires car would that be down around here or is that more Gloucester way ??. 

[JamesV6CDX]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

The car seems to run worse during warm up, dose not seem to affect acceleration up through the box its becomes apparent when moving at lower speeds.

If I get Claires car done on Saturday in good time I'd be happy to take a look...

Thanks James for your offer will try tightening them first possibly tomorrow afternoon see how it goes. If she still plays up will make contact, your doing Claires car would that be down around here or is that more Gloucester way ??. 

It's actually the other direction... but, I'd happily keep going on the M5, on the way home, for the sake of a beer token to cover the LPG

Could run some diags, look at the live data and see if we can determine any issues

[SteveAvfc.]

The condition of the plug is not a reliable indicator of how an engine's running, in reality. You might get a clean plug if the engine was cut immediately after being driven under load, but a few seconds of idling and the plug will cool and collect a layer of soot.

I would say the plugs are unlikely to be the problem but if they haven't been changed recently then it won't hurt to try some new ones.

They do have a habit of coming loose. The trick is to tighten them to 25Nm, leave them for a few minutes, then go round them again and double check.

So, on to the running problem. Any fault codes stored? Is it running poorly just at idle or under load? Throughout the whole rev range or just in one place?

The car seems to run worse during warm up, dose not seem to affect acceleration up through the box its becomes apparent when moving at lower speeds.

If I get Claires car done on Saturday in good time I'd be happy to take a look...

Thanks James for your offer will try tightening them first possibly tomorrow afternoon see how it goes. If she still plays up will make contact, your doing Claires car would that be down around here or is that more Gloucester way ??. 

It's actually the other direction... but, I'd happily keep going on the M5, on the way home, for the sake of a beer token to cover the LPG

Could run some diags, look at the live data and see if we can determine any issues

Hi James have PM you Steve.