Spark Plugs

[craig_the_german]

Hi All,

This is not strictly VW related but could apply to almost any car.

I have just returned from a caravaning holiday (had a great time mind you ) and before I went I decided to give my tow vehicle the "once over" so to speak.

Oil and filter change, fresh set of spark plugs, grease and lube all round...as you do. There in lies the problem.......

Prior to changing the spark plugs, the vehicle was running perfectly. The plug change was more for piece of mind than anything as the plugs hadn't been changed for a while.

Almost from day one, the vehicle developed a misfire when under load (towing a campervan puts it under load most of the time).

I put it down to maybe a faulty spark plug as it ran perfectly before. Since returning, I have put the old plugs back in and the misfire has gone away.

The question is...what makes brand new spark plugs misfire? I have checked the gaps, checked for cracks, generally anything that might be wrong and all appears fine.

The plugs in question were Bosch Platinum+ (made in Germany) and were the plugs specified for the vehicle.

What's everyone's thoughts?????

Thanks

[h100vw]

They just do mate. Put the new ones back in one at a time and find out which one it is, then buy one more.

I had a mis develop in my S3 with a new set of plugs. You can't take anything out of the equation when troubleshooting. Even new parts.

Gavin

[Transporter]

Check the spark plug leads as well. You may have broken wire.

But, also as Gavin said, it could be just a faulty brand new spark plug.

[Jmac]

Yeah new plugs could have been dropped in the parts dept mate. Having said that i agree with the leads comment, A new set of plugs will show up a weak lead mate. You can get a decent lead set for your AKL motor from Imparts at a decent price, they will most likely be due to be replaced. Seen it before engine is fine till you fit new plugs
Cheers
Jmac

[Mrk_Mickey]

While it may or may not be the problem, personally I think it's a good idea to change the leads anyway. Chances are the leads on your car are getting on by now, and they're probably getting closer and closer to failing anyway.

[Jmac]

I agree mickey, back when i was with Dub in the UK mate we were changing leads at services galore, we hooked the car up to a KV reader which read the resistance on the leads and found them crap at 40k miles ( 60Km) back then Quantum were the big suppliers of leads for all VAG ( tears) they really were the days, thats when a G60 Corrado came in for a service and you caned it and took it for granted hmph!!! An S2 came in for a wastegate spring and chip.Hmph!! Ah well, here we are
Change the leads, imparts do them very cheap, and they are all numbered like the VAG set up
Cheers
Jmac

[craig_the_german]

Thanks for the info guys.

The vehicle is actually my Holden Jackaroo 4wd that I use to tow my camper.

The old girl has done 207000km on the original leads so I guess I could put a set on now....

[gregozedobe]

The old girl has done 207000km on the original leads so I guess I could put a set on now....

May be nearly time for a distributor cap too (and a rotor button if it has one).

[gerhard]

Thanks for the info guys.

The vehicle is actually my Holden Jackaroo 4wd that I use to tow my camper.

The old girl has done 207000km on the original leads so I guess I could put a set on now....

If it's the 2.6l engine, it's hardly even run in. Kumbak in Melbourne uses Rodeos with this engine as delivery vehicles, and they have over 700,000ks without touching the engines. Like the 3.5V6, it's not an easy engine on fuel, but it just keeps on going.

Could be weak coil as well.

[Mrk_Mickey]

Yeah Jackaroo's are the sheet! My mate's dad has one that my mate learnt in....hammered the clutch all the while he was learning and it still hauls ass. 220,000km on the original clutch too, somehow...