Pat_McCrotch 0 Posted February 11, 2012 The VR has developed a slight missfire when cold but seems normal when up to temperature. Is this a sign of a coil going down? :( Is there any physical way to check? Quote Share this post Link to post Share on other sites
MarkFoster 0 Posted February 11, 2012 Take it round to Uncle Kev's - he'll know what's best for the sickly child...! ---------- Post added at 03:54 PM ---------- Previous post was at 03:48 PM ---------- Actually, and perhaps more helpfully, if you've checked the leads and coilpack; have a look at the MAF plug. I had all manner of hassle with mine and it turned out there was a bit of moisture in the plug which would pop the plug off after a while and cause a missfire type problem. I suspect the moisture got in there from condensation during the cold weather which can't escape unless you physically get into the plug and blow it all out. Might help M. Quote Share this post Link to post Share on other sites
Jim Bowen 1 Posted February 11, 2012 yep, could be moisture around the coilpack/leads. i usually check by spraying some water on that area and can sometimes see/hear the sparks escaping. Quote Share this post Link to post Share on other sites
Pat_McCrotch 0 Posted February 11, 2012 I'll get to work on it tomorrow if it's not too cold :) Quote Share this post Link to post Share on other sites
Stonejag 10 Posted February 12, 2012 There must be something in the water, mine lost a coil earlier :( It'd been running a bit rough when it got wet for the past few weeks (then recovering) but the cold weather must have finished it off. I start a new job tomorrow and was on a dry run to remind myself of the route in - lucky I did or it would have failed on the way in on my first day :lol: I've got a spare - with a crack in - I've just poured a load of epoxy into it so hopefully it will last me long enough to get a new one... Stone Quote Share this post Link to post Share on other sites
huggy 0 Posted February 12, 2012 Yep had the same issue in the dark and with the engine running cold mist some h2o over the engine look down the tunnels that lead to the spark plugs you will proberly see a spark arc, swap the leads out for some new ones and done Quote Share this post Link to post Share on other sites
Stonejag 10 Posted February 12, 2012 Well, I swapped on my epoxied coilpack and it's running fine again :) The leads were new about three weeks ago so I was confident it wasn't them...do check yours though. FWIW my coilpack was totally knackered and you couldn't see a thing when it was misfiring! The crack was right down the edge closest to the slam panel so cylinders 1 and 6 had dropped out. Stone Quote Share this post Link to post Share on other sites
Jim Bowen 1 Posted February 13, 2012 I spose at this time of year any moisture in the coilpack will freeze and expand @Pat/Neil I have a coilpack and leads from my corrado just doing nothing at the moment if you needed to experiment with anything before forking out for a coilpack etc Quote Share this post Link to post Share on other sites
VW_OwneR_85 2 Posted February 14, 2012 Take it round to Uncle Kev's - he'll know what's best for the sickly child...! ---------- Post added at 03:54 PM ---------- Previous post was at 03:48 PM ---------- Actually, and perhaps more helpfully, if you've checked the leads and coilpack; have a look at the MAF plug. I had all manner of hassle with mine and it turned out there was a bit of moisture in the plug which would pop the plug off after a while and cause a missfire type problem. I suspect the moisture got in there from condensation during the cold weather which can't escape unless you physically get into the plug and blow it all out. Might help M. That was the problem with mine, the previous owner said it allways had an idle problem but couldnt find out what, how ever it was fine when i picked it up, i only found out about it when i was washing my bonnet, the way the maf cable is routed it would allow water to run down into the plug itself, the symptoms were if it was just damp it would miss under load and idle abit irraticaly, if the plug was absolutley flooded it would idle up and down from 600rpm to 1500rpm then the battery light would come on then cut out and was un driveable!! quick blow out and a squirt of wd-40 and its back to normal.. Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 14, 2012 Usual checks:- 1) Push HT leads down firmly onto the spark plugs to make sure there are no partial connections. 2) Push HT leads firmly onto coilpack to make sure there are no partial connections. 3) With engine running at night, get a water sprayer with a fine mist and spray the coilpack and plugs and check for arcing. 4) If at that point nothing springs out at you, life the plugs and check for oil fouling. Bear in mind we've had temperatures fall below -10 recently, and it the car is kept outside, it's going to cause cracking problems on old coilpacks as it warms up. Quote Share this post Link to post Share on other sites
Pat_McCrotch 0 Posted February 15, 2012 Right, did the spray bottle test and did about 3 minutes of spraying. It arc'ed about 2-3 times on the lower part of the coil? If it was fubared would it be doing it constantly? Or is the fact it's arc'ed at all a sign it's fooked? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 15, 2012 Shouldn't arc at all mate Quote Share this post Link to post Share on other sites
Pat_McCrotch 0 Posted February 15, 2012 Bugger :( £250 bill it is then! Quote Share this post Link to post Share on other sites
lewvw 10 Posted February 15, 2012 Bugger :( £250 bill it is then! If thats £250 to you whats the retail on that bad boy? Quote Share this post Link to post Share on other sites
krishen 2 Posted February 16, 2012 I had mine replaced few weeks ago. Think it was £100 plus vat for the coil. Quote Share this post Link to post Share on other sites
Jim Bowen 1 Posted February 16, 2012 I used a beru one and has been fine for years now Quote Share this post Link to post Share on other sites
Pat_McCrotch 0 Posted February 16, 2012 If thats £250 to you whats the retail on that bad boy? £333.00 including VAT! Can get one from ECP for £106 + VAT which is a BERU. But might have another solution... Quote Share this post Link to post Share on other sites
Trickygti 0 Posted February 16, 2012 I've just bought a cheap one off Ebay as mine was missing when first starting when cold but then clearing up. Cost me £72 delivered and car runs alot better with it. Could get a new genuine one for £150ish but just needed something to keep me going for the time being. Mine had a crack right under no'5. Quote Share this post Link to post Share on other sites
Johnny H 0 Posted February 18, 2012 I'm having the same problem but i've got a new coil pack and new plugs and just changed the leads to 2nd hand ones but was told they arent very old and are in very good con. Could it be the MAF or the Throttle Body needs cleaning or the dizzy cap?? Its doing my head in now. Its got a cold start prob where i need to give it a lilttle rev for about 1 min and then it will tick over and then it has a small missfire at low revs. Can anyone help me with this?? PLEASE??? ---------- Post added at 06:51 AM ---------- Previous post was at 06:49 AM ---------- Bugger :( £250 bill it is then! I got an genuine one for £145 inc vat Quote Share this post Link to post Share on other sites
Stonejag 10 Posted February 18, 2012 (edited) Bloody hell, £333?! I bought an own-brand one from GSF this morning for £78 inc VAT, with a one year warranty! Johnny: tried cleaning the MAF? Run it for a bit, then kill the engine by turn the key to the accessory power position and leave it there for 30 arcs before turning off - the ecu should keep the wire heated and burn any crap off it. Cheap so worth a try! If not then also make sure the MAF connector is clean and free of water before spending any more... Stone Edited February 18, 2012 by Stonejag Quote Share this post Link to post Share on other sites
Johnny H 0 Posted February 19, 2012 Bloody hell, £333?! I bought an own-brand one from GSF this morning for £78 inc VAT, with a one year warranty! Johnny: tried cleaning the MAF? Run it for a bit, then kill the engine by turn the key to the accessory power position and leave it there for 30 arcs before turning off - the ecu should keep the wire heated and burn any crap off it. Cheap so worth a try! If not then also make sure the MAF connector is clean and free of water before spending any more... Stone ?? Sorry for sounding a bit think but I'm not sure what you mean mate?? Quote Share this post Link to post Share on other sites
Pat_McCrotch 0 Posted February 19, 2012 (edited) Bit of an update. Took it out for a spin yesterday after taking it off SORN. Ran like a dream! I think given the number of times it sparked when I did the spray test I think it's in very early days of coil failure so I shall monitor it and see how i get on :) Edited February 19, 2012 by Pat_McCrotch Quote Share this post Link to post Share on other sites
Stonejag 10 Posted February 19, 2012 ?? Sorry for sounding a bit think but I'm not sure what you mean mate?? Sorry, predictive text ('secs' became 'arcs') - made that a little unclear! Run the engine for a bit, then turn the key one click onto the accessory power position to kill the engine, and leave it there a few seconds. (supposed to be 10 seconds but give it 30 to be safe) The MAF works by heating up a platinum wire and measuring the resistance - the more air comes in the more the wire is cooled, and hot metal has higher resistance than cold metal so the ECU can work out how much air the engine is sucking in by how much the resistance drops. Doing the above heats the wire up with no air cooling it, so it gets nice and hot and burns off any accumulated crap that might make it give a false reading. Stone Quote Share this post Link to post Share on other sites
Johnny H 0 Posted February 20, 2012 Sorry, predictive text ('secs' became 'arcs') - made that a little unclear! Run the engine for a bit, then turn the key one click onto the accessory power position to kill the engine, and leave it there a few seconds. (supposed to be 10 seconds but give it 30 to be safe) The MAF works by heating up a platinum wire and measuring the resistance - the more air comes in the more the wire is cooled, and hot metal has higher resistance than cold metal so the ECU can work out how much air the engine is sucking in by how much the resistance drops. Doing the above heats the wire up with no air cooling it, so it gets nice and hot and burns off any accumulated crap that might make it give a false reading. Stone Hi Stone, I gave it a go this morning and think it's helped so it must be the MAF. I'm going to take it out and give it a clean tomorrow and hope it does the job. Thanks for your help bud Johnny Quote Share this post Link to post Share on other sites
huggy 0 Posted February 25, 2012 If you haven't alrealy look up how to clean a MAF witch contact cleaner if I recal, the MAF is very sensitive and quite expensive Quote Share this post Link to post Share on other sites
