pete_griff 0 Posted February 9, 2008 my car has developed a sporadic missfire yesterday thats become more frequent now, but is still not there all the time which makes me instantly think fuel. it's just had new leads/plugs/coilpack and it does make a difference (even if it is only a little) when taking off each lead one at a time while it's running. i've just done the head gasket and obviously replaced all the other gaskets (inlet/exhaust etc) so i'm pretty certain there's no air leak anywhere, and also up until now the car has been running really well. i'm getting white smoke which stinks of fuel and i had to change all the injectors from one manifold to another owing to mine breaking. i'm guessing that it could only be the injectors now - anyone got any other thoughts... also have sourced some more injectors that are reconned/flow tested etc for approx £65 that i will hopefully buy in the next day or two also can someone confirm that this is the part number for me - Part number: 0 280 150 953 cheers Quote Share this post Link to post Share on other sites
pete_griff 0 Posted February 9, 2008 another question while i'm on the subject - i've never had any experience with VAG-COM or whatever it's called. how good is the diagnostic on old cars like the 'rado vr6 (mine's 1993). also i take it a decent vw garage would be able to sort me out with reading it and codes etc... as i know a friend who works at a vw dealership if it's any good it might help me shed some light on whats going on. also i've noticed my speedo (again since yesterday) has started to drop all of a sudden to zero then back up (after wobbling around a bit) to the speed it should be (lucky i use a road angel). also the engine oil temp seems to be reading very low all of a sudden compared to what it normally does - car's got plently of oil in, pressure is ok, but after a "spirited" drive down my favourite b-road which would normally see the temp rise to 115 and above, it's reading very low, like 60-70 at most, then dropping right off after the car has sat still for 5 mins. i had to re-solder a load of new wires in where my exhaust got so hot it melted the ones that run over the exhaust tunnel just behing the gear shift-mech - could my instrument troubles be caused by more melted wiring elsewhere, and if so where, asi can't think that it would cause melting anywhere else? cheers again Quote Share this post Link to post Share on other sites
pete_griff 0 Posted February 9, 2008 any help from anyone would be really appreciated, as i don't really want to shell out on a new set of injectors when i don't need them. also has anyone in/near hereford got VAG-COM as i would happily pay to be able to use it... Quote Share this post Link to post Share on other sites
dr_mat 0 Posted February 9, 2008 "white smoke, stinks of fuel" .. is normal during cold start cycle, but should go away when the engine is warm. If it's massively overfuelling then it could be MAF / lambda / stuck injector or even an ECU fault. What colour are the plugs? If one is noticeably different from the others you might have a problem with that injector. Have to say tho, £65 for a set of cleaned injectors is pretty cheap! Quote Share this post Link to post Share on other sites
pete_griff 0 Posted February 9, 2008 "white smoke, stinks of fuel" .. is normal during cold start cycle, but should go away when the engine is warm. If it's massively overfuelling then it could be MAF / lambda / stuck injector or even an ECU fault. What colour are the plugs? If one is noticeably different from the others you might have a problem with that injector. Have to say tho, £65 for a set of cleaned injectors is pretty cheap! cheers dr-mat totally agree with the price - V cheap; from the states though, so they'll take time to arrive. i'm pretty certain it's fuel as it was doing it when warm sporadically during/after a drive and it varies in just how bad it actually is, and it literally just started out of the blue yesterday - never done it before... i'll defo check the MAF though, should have thought of that really, cheers any other ideas anyone? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 11, 2008 The speedo dropping out is usually a sign of the gearbox sender starting to go or the Voltage regulator on the Clocks. Both easy to correct. Gearbox sender obviously a simple case of replacement, only about £20. The Voltage regulator is a few quid from VAGparts.com under their 'misc' section. If you take out the clocks, you'll see a blue PCB and you'll see the reg on the back there, which is a black tranny with 3 prongs. Sometimes the solder joints just go dry and need redoing, so try that first. Mine was the same, rev counter dropping, weird temp readings etc and resoldering the reg did the trick. If you suspect your injectors, i can stick some standard ones in the post to you to try? Quote Share this post Link to post Share on other sites
was8v 0 Posted February 11, 2008 I had the same missfire plus white smoke stinks of fuel, was a duff injector. Whip the plugs out and see if one stinks of fuel. If so swap injectors with another cylinder and see if the problem moves to that plug. Apparently its easier to remove/ replace injectors with the engine warm. Probs best to change the oil after as the unburnt fuel may have washed down the bores. Quote Share this post Link to post Share on other sites
fla 9 Posted February 11, 2008 Clean the injectors by opening them with a 1.5V direct power supply and flush them with an injector cleaner. Then change teh seals, there is an o ring and an energised lip seal which may be failing. I'm trying to get hold of some lip seals from a few manufacturers as they cost about a fiver EACH from GSF, God knows how much from the stealers. Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 11, 2008 VAG-COM has injector and coil test cycles. So long as the injectors are in the rail and secured with the circlips, you can extend the fuel lines to move the rail a few meters from the car and then fire them up into a bucket or something. Works a treat as you can also check the spray patter of each and make sure they're uniform. I never ran the test cycles when I had Motronic and you do so at your own risk :-) I have run them on standalone though and they're invaluable for fault finding. Personally, if the injectors are duff, I'd import some new ones from the states (they're 210cc @ 3bar) but the Rochester or Delphi brand. Better and cheaper. Quote Share this post Link to post Share on other sites
pete_griff 0 Posted February 12, 2008 cheers for all the advice gents - well appreciated kev it does sound like the connections on the back of my clocks need attention, as i've been getting some very strange readings etc. thanks again for the offer of the injectors, but to be honest i'm getting pretty pi$$ed off now with fixing the car and pouring money into the engine, when i'm only going to replace it at the end of this year with an r32 unit, so this weekend i limped it to where it's going to live for 6 months and i'm just going to leave it there. i'm off on my 6 month "holiday" very shortly, so frankly i just cant be arsed to keep on throwing money and time at something that i'm not going to see the benefit from. i would much rather it was driven round for the 6 months i'm not here, but i've run out of patience now as it's spent more time off the road than on it so far! edit: - another thing, my friend who is looking after it for me took the car up the road the other day and said that it was perfect - plenty of power and didn't missifre once!... the saga continues! edit edit: - i'll try and put this in the correct thread this time :ignore: Quote Share this post Link to post Share on other sites
