UK-POLOS.NET - THE VW Polo Forum

Last year while driving my Polo 1.2SE in the snow, I was left a bit stranded when one of my coil packs died, leaving me with effectively 2 cylinders. Prior to the failure, out of the 3 coil packs, 1 of them had been replaced recently, with two older ones fitted from before I bought the car (it was one of the older ones that died). On the recommendation of the garage, I had the two older coil packs replaced. This was in January earlier this year, and I had given it no thought since.

However, I was on the M1 this evening, just approaching the M25 having come all the way down from Sheffield (left in absolute blizzard conditions!). Suddenly, I get an emissions light and I find my power is dying. I end up crawling along in the slow lane at 60 with my foot on the floor, going little over 45 on the hills. I suspected I'd lost a coil pack again, but decided to soldier on and run out the motorway as far I could to minimise the looming rescue mission from home! My fears were confirmed as I pulled off the M1 onto the slip road of my junction. As I dropped below 40mph, the accelerator suddenly became response-less. Flicked the hazards and stuttered along at about 10mph until I found a residential street. Came to a standstill, shut everything off and sat for a second dreading having to call out a tow. But for whatever reason, I gave the ignition another go. Hey presto, engine turns over perfectly with all 3 sparks firing. I continue my journey and get home fine.

Sorry about the essay of a story, but I've got a few questions for all you knowledgeable folk as a result of this experience...

Why do these coil packs seem so temperamental when exposed to a bit of cold? Am I doing something wrong here? Surely after 100 miles of 50-80mph motorway driving, everything would be warm and ticking nicely.

In terms of going about a repair, what would you suggest? Is this isolated problem and indication that the coil in question is about to fail totally, or might I get a fair few more miles out of it?

Thanks for any help guys!

Could be an electrical issue on the coils mate with wetness from the road seeping into the bay and playing about with a loose connection?

Would explain the tempremental nature of the problem anyway, have a look about see if you can spot any strained/split/loose connections.

Worth a go

Sepi

The big deal with these coils I think, is that the insulating "potting" compound either shrinks or cracks with age due to the manufacturer using the wrong process or wrong material. After this shrinking and/or cracking takes place, small openings exist in the insulation - round about high voltage coils - water gets in - and the rest is history! It could be that these COP or pencil coils are just designed badly. One interesting thing to note for the future, the new 1.2 4 cylinder range of TSI VAG engines seem to use a single (old style) coil pack with EHT leads going to the shrouded plugs. This turns the clock back about 10 years in VAG ways of thinking - but might cure a few potential problems!! I should not boast about this, but "just" before a coil failed on my wife's 1.4 Polo, I bought a NOS one from ebay - a week later it was put to use, it was the same build date roughly as the factory fitted ones - and the same brand. That was about 5 years ago, have not had any more problems yet, although since that used up my spare coil, I bought another - newer manufacture date - again from ebay.

I reckon that you should get a fault scan done on your car - or do it yourself using one of these cheap Gendan VAG fault code readers - about £40 delivered I seem to remember. By doing that you should discover what the car thought was happening - you should get a mis-fire being reported - along with a cylinder number,then clear the logged fault(s) after noting them down. On the other hand, you might get something more interesting reported. Remember to check up on the warranty that VAG is currently giving with these coils - that is assuming that your garage was a VAG garage and it fitted VAG sourced coil packs - as it seem that there are some cheapies about from other sources.

Took the car back to the garage where I originally had the work done today. The guy there seemed to think there was no point doing a diagnostic as, since the misfire wasn't still happening, it wouldn't read anything. He said the fault codes weren't stored. Don't know how much truth there is in that really. How easy are those Gendan things to operate? I'm guessing it's all pretty restricted so you can't mess too much up! I've heard the fault code list they provide isn't very extensive either and you have to source the comprehensive one elsewhere. Is this true?

Thanks

I've got the hand held Gendan one, its pretty damn good for £40 to be fair.

Comes with a big booklet which covers 99.9% of the codes it throws up, though any others are easily given with the CD it comes with along with a quick google.

Great tool.

You can only read codes + clear so you cant mess anything up at all, it cant reprogram anything...

I agree that the Gendan scan tool is good, it will pick up any engine, ABS, SRS or AUTO TRANS codes that get logged - in exactly the same way that VAG-COM ie VCDS will do, though VAG-COM and VCDS will always add an appropriate label to the code - ie explain it in English as well as the VAG code number and where appropriate the OBD11 code number. It is very easy to get hold of an extensive - or maybe complete VAG code listing on-line as its true that the CD that Gendan supplies is a bit on the short side - but as said getting that listing is easy - its best to start looking for that list when you order the tool, as, in my case (I also have VCDS) I keep the Gendan in the glovebox of my car, first two times I used it, it picked up the code okay but it was not on the list! So much for "I'll tell you what is wrong in a couple of minutes" - all I got has a hunch and a red face - but at night after some surfing I managed to put a name to both the missing codes. Why could not these two cars just chuck out old well tried and tested codes - it's not fair!!

BTW, your garage telling you that it would be a waste of time looking for logged codes is not being very helpful! If the fault warning indicator was switched on then I'd expect that a code would have been logged - so yes, go your own way and get that cheap Gendan scan tool - it might just be worth its weight in gold.

sep_rider wrote:I've got the hand held Gendan one, its pretty damn good for £40 to be fair.

Comes with a big booklet which covers 99.9% of the codes it throws up, though any others are easily given with the CD it comes with along with a quick google.
Great tool.
You can only read codes + clear so you cant mess anything up at all, it cant reprogram anything...

I did not have much luck with the supplied CD - I seem to remember that it came up with an error or problem - I was using it with a Vista SP2(?) laptop - but the internet search quickly yielded a HUGE listing for VAG - so that list now travels with the Gendan tool.

When you guys mention the Gendan tool, did you buy the 'Gendan GCR05 EOBD/OBDII Fault Code Reader'
- £39.95 or the 'Gendan VW Audi Seat Skoda Code Reader' - £39.10?

Cheers

tim80bwi wrote:When you guys mention the Gendan tool, did you buy the 'Gendan GCR05 EOBD/OBDII Fault Code Reader'
- £39.95 or the 'Gendan VW Audi Seat Skoda Code Reader' - £39.10? Cheers

For VAG only use and to include "looking" at ABS SRS or AUTO TRANS as well as engine, then get the second one, for engine only and only EOBD codes on any European car that is meant to comply with EOBD requirements - and some that should but don't (Fords! I discovered), get the first one. From what your requirements seem to be, if I were you I'd get the VAG one - ie VW Audi Seat Skoda Code Reader.

Cheers RUM4MO

For future refrence if anyone wants to quickly scan their car etc and is in the midlands area, very welcome to use mine