Its another misfire thread.

[Howrare]

Poor Tolly. Sitting not getting used much in down to -25C temps has obviousley messed with her sensibilities a bit.

I'm starting a new thread to see if I can get some answers from experienced posters or mechanics. Please refrain from the usual "could be this, could be that" posts. Sorry to sound a little negative when asking for help, but I have spent hours trawling the various VAG forums, and confusing myself. There is so much conflicting info out there, and posts from those that are obviousley just poking about under their respective bonnets.

So to the symptoms.
AE AEY had been running peachy, but then noticed the slightest hessitation whilst driving up a gentle incline. It cleared itself and didn't do it again for the rest of a fairly long journey. Having been aware of the V5 (and VAG in general) coil issues, I thought it would probably be one of them on the way out.

Next time I used the car it ran for 5 minutes in it normal creamy smooth manner, then started missing pretty badly. Very much felt like a cylinder was down. ECL on and flashing when I gave it some gas. It got home though. Note that it was still running rough as a badger whilst at idle.

Once cooled down I checked the coils and indeed no.2 was in bits. So ordered a new Bourgicord one. (Mines a 170BHP 20v BTW) Fitted it, and she was back to idling perfectly. Also it would rev through the whole range very cleanly. Guess the new coil is behaving properly. HOWEVER, I took her for a test run and as soon as the engine temp started to rise, she started to misfire again. Only slightly at first, but as temp reached normal I had a very strong mis at around 2000rpm. I kept my foot in and got the revs over 3500-4000 it was much better.

First question. Does the car need to be put on VAGCOM after a coil pack has been replaced?

Second question. As the car now idles properly, and drives fine whilst cold, this to me would suggest the coils are now working as they should. Would you agree?

Third question. Does the misfire when warm suggest that my car is ready for its third MAF of its life?

Forth question. Can a MAF be replaced without resetting the ECU via VAGCOM?

Fifth and final question. I have read about temp sensors, and lambada probes leading to similar issues. Can these be islolated without resorting to VAGCOM (PS I was being funny about the la la la lambada probe.

As mentioned above I would be very very greatful that answers are given by those that really really know thier VAG onions. As I am in Austria, those kindly folks out there with VAGCOM that can do diagnostics down at the local Macca D's car park just don't exsist. The local VAG dealer can do it, but are going to charge me the earth just to plug her in and get the codes. Also if it is the MAF or Klapper, as the call it here (oooo dear missus me cars got the Klap) then the bill is going to be massive. Around €500 at the least. Simply not worth it.

Hope a few of you with grease under your nails can help,
Kind regards
Larry.

 

[Paul. W]

Hi there.

First question. Does the car need to be put on VAGCOM after a coil pack has been replaced?
Nope, a new one just works straight away.

Second question. As the car now idles properly, and drives fine whilst cold, this to me would suggest the coils are now working as they should. Would you agree?
Yes I'd agree

Third question. Does the misfire when warm suggest that my car is ready for its third MAF of its life?
Its a possibility!

Forth question. Can a MAF be replaced without resetting the ECU via VAGCOM?
Just disconnect the battery for 20 minutes or so then take it for a decent drive. It'll relearn its values.

Fifth and final question. I have read about temp sensors, and lambada probes leading to similar issues. Can these be islolated without resorting to VAGCOM.

Not really. VAGCOM will give you a MUCH better idea of what to tackle. I'd have no idea that my pre-cat lambda sensor heater had broke causing it to run in a cold loop. I now have an extra 80 miles to a tank! No light or EML for the whole time.

Getting the codes read will save you heaps of time, and probably money. If you have a vacuum leak (like I have atm) then you know to start checking all the pipes. When you say it missfires at around 2000rpm, is it just a loss of power blip, or does the EML light still flash? My hesitation at 2000rpm is being caused by a vacuum leak.

 

[Howrare]

Thanks Paul, looks like I'll have to find a localish dealer that can pop in on a diagnostic for a sensible amount of euros then.
As for the vacuum hoses, I'll give them the once over. The EML light stays on all the time, and then when I give her some gas it starts to flash. it then returns to a solid light when revs drop again. It does all feel like an carbed engine that I've forgotten to adjust the choke on. Last time it ran completely fine it was utterly baltic in my kneck of the woods. The other day when I started out on a small journey it was much warmer and it was bogging down a little when cold.
Perhaps the MAF is stuck in its last cold setting?

I guess as you say I should just bite the bullet and get it hooked up to the 'puter. I could go round in circles for ages otherwise.

Thanks again for the reply, it was most helpful.

 

[Paul. W]

You could unplug the MAF and go for a drive. The car will run on a default map, and will help eliminate if your MAF is faulty.

If the EML light is flashing then I'd personally sway towards a bad sensor. Still guesswork though.

I dont have VAGCOM myself, I just bought a cheap VAG 405 reader off ebay, link here:
http://www.ebay.co.uk/itm/221153442887

Obviously not as advanced as VAGCOM, but it will reset EML / Airbag / ABS lights and codes. Suits me perfectly, I've already made my money back on it with the countless times I've used it.

 

[Howrare]

Not going to shout about man points just yet, but I have managed to get a VAGCOM cable, downloaded VCDS-Lite from Ross-tech, loaded it all up, and got a diagnostic readout of my Tolly. Yay me.

Looks like you were right Paul

16804 - Catalyst System; Bank 1: Efficiency Below Threshold
P0420 - 35-10 - - - Intermittent
16523 - O2 Sensor Circ. Bank1-Sensor2 Slow Response
P0139 - 35-10 - Please Register/Activate - Intermittent

There was a bunch of other stuff pertaining to random misfires and also the log of when I was trying to locate which coil pack had gone.

Question is learned folks of Cupra.net. Which O2 sensor is it. The one in the exhaust? Or are there others?

Thanks in advance.

PS I bought a Gendan KKL cable for about £20. Looks exactly the same as the chinese ones on ebay, but hey, rather have a little back up for the sake of 15 squid.

 

[Paul. W]

Excellent, glad you got a code reading solution sorted

The codes you're getting relate to the post cat lambda sensor. Bank 1 relates to the bank of cylinders - In our case it'll only ever be one (V8's for example would have bank 1 and bank 2). Sensor 1 is pre-cat and sensor 2 is post cat.

I'd certainly replace the post-cat sensor. They're quite easy to access on the Toledo, you just need the correct sized spanner (or lambda socket to make life very easy).

Other things that could possibly trigger them codes according to ross-tech is an air intake leak (split vacuum pipe etc). Its worthwhile having a look round your vac pipes, especially the PCV breather hose at the top. However I'm banking on a new sensor

 

[Howrare]

Paul you ledge, talk about a swift reply.

I have a friendly ex landlord with an inspection pit in his garage. I'll see if I can get her in there and have a root around. I did have a good look at the hoses last time I had the bonnet up. Looked in pretty good shape. I'll get a lamp in there and move them all about a bit to see if there are some tiny splits I'm missing.

I'm hardly using the car at the moment. Living in a bit of an alpine bubble, and having smashed up ribs, means I don't really need it. Sods law though I need to go to Innsbruck this week. Could driving
it in this condition bugger the Cat up?

Thanks so much for the help.

 

[Paul. W]

The cat wont instantly destroy itself, your car is probably running richer or leaner than normal though to compensate. Its certainly not as bad as driving round with a knackered coil pack dumping unburnt fuel straight into the cat.

As long as you fix it soon enough, it'll be ok.

 

[Howrare]

Been a little while getting this sorted. Finally got a new post cat probe fitted yesterday. Managed to get a direct fit Bosch one for €75 which I though was pretty good, and a local spannerman popped it in, did a diag scan and checked all the vac hoses for €30.

She's certainly running much better, but STILL misfiring. Scanned her again today, and another coil pack has failed. I have given up, and ordered another 4 coils, so that they are all new.

One more 1000m trip back to the UK, and my time with AEY will be at an end. GF's 207HDi is much newer, (and much more boring) but coming travels need to be paid for so the Tolly must go.

 

[Paul. W]

Sorry to hear that Howrare. What mileage are you on with that now? Are you hoping to sell in the UK or back at home?

 

[Howrare]

Hello Paul,

About 108000 by the time she gets back into the country on the 20th. I'm based in Suffolk in the motherland. I've popped full details on the for sale section and pics.

 

[Howrare]

Well AEY stormed back from Austria and without a stutter. Misfire fully sorted. 1000 miles was dispatched in quiet comfort. I don't want to get rid of this car Have to though, and I have run out of time to get it sorted.

Any offer considered!!

http://www.gumtree.com/p/cars-vans-...o-v5-20v-170bhp-2001-must-go-today/1015779073

 

[Paul. W]

Howrare!

You made Pistonheads SOTW!

http://www.pistonheads.com/news/default.asp?storyId=27613

That'll get you a decent audience!

 

[adaminnit]

just chucked two new coils on my v5. funny how they seem to go at the worst possible time!

 

[Howrare]

I was immensely chuffed to make Pistonheads SOTW. By far my favourite part of that site. AEY went to a fella from Darlington who had an identical spec one to mine but with 170k on the clock. He'd had it from new and loved it. His vari valve timing had gone south, so rather than fix his, he bought mine. Very glad it has gone to a good home.

The GF's 307 HDi, is an utter bag of poop in comparison. Horrid build quality and a dire stereo being the first impressions of it. It will be rather less fond of a drink though.