68vitesse Posted January 6, 2021 Report Share Posted January 6, 2021 (edited) My Vitesse misfires on first start of the day which then clears and car fine for rest of the day, no coolant loss and low oil consumption. Today I removed the plugs when cold, NGK BP6ES, to find numbers 4 and 5 difficult to remove all plug electrode's look ok but number 4 plug is eroded or corroded at start of thread near electrode number 5 not so bad. Just changed these two plugs for a couple of new champion plugs and car started without a problem and ran fine while I did my food shopping. Don't know if this is a permanent fix and wondering if these are fake plugs, never had a problem with NGK before. Regards Paul Edited June 27, 2021 by 68vitesse Update Link to comment Share on other sites More sharing options...
Peter Truman Posted January 6, 2021 Report Share Posted January 6, 2021 can't comment on the corrosion issue but around 8 years ago I brought 24 new NGK BP6ES plugs as a job lot at a club meeting over the following 8 years there've all failed ie the Pete Lewis advised saturation of the non glazed insulator, I put the last 2 in a couple of weeks ago. Maybe they were cheap for a reason! The issue is how I start the car so as to get oil circulation before firing the engine after she's stood unused for a while, choke in spin the starter for 8-10sec then pull the choke and churn for another couple of secs then she fires, she is obviously flooded a little as she runs rough then clears. With an unglazed plug insulator it gets saturated and fails, there very hard to dry out and clean sometimes its fixed the issue for a short period but once there've been saturated their life expectancy appears short, Being honest because I had a good supply I just replaced them. I'm now looking for Bosch replacements, but for some reason there getting hard to source here locally in Melbourne almost as if Bosch are limiting there supply! NGK virtually have the market covered esp with the major aftermarket suppliers. Ridiculous as it sounds I'm looking to source plugs from the UK, and pay the shipping Link to comment Share on other sites More sharing options...
Pete Lewis Posted January 7, 2021 Report Share Posted January 7, 2021 here's a link to the original ideas of NGK and others failing on carb. cars Link to comment Share on other sites More sharing options...
johny Posted January 7, 2021 Report Share Posted January 7, 2021 All this has made me think that my policy of keeping the same plugs (so long I cant remember when but certainly 25+ years) has been a good idea. Admittedly over that time Ive only averaged about 1000 miles a year but I just clean/gap them and back in they go - after all we're talking a tractor engine here not F1.... Link to comment Share on other sites More sharing options...
Pete Lewis Posted January 7, 2021 Report Share Posted January 7, 2021 4 hours ago, johny said: tractor engine here not F1.... its all down to modern fuel injection runs without any major enrichment like you get withma choke /carb system that plug design parameters have changed to suit present running conditions it doenst say when these changes came about but certainly many members have found early life plug break downs on certain plug makes lots of short cold runs will not help , plenty of good hot running obviously should help pete Link to comment Share on other sites More sharing options...
johny Posted January 7, 2021 Report Share Posted January 7, 2021 Interesting, so old plugs might be best - I love it when Ive saved money AND done the right thing! Saying that now one of my ancient plug electrode will probably snap off and bounce around in a combustion chamber😵 Link to comment Share on other sites More sharing options...
68vitesse Posted January 7, 2021 Author Report Share Posted January 7, 2021 Found this for modern cars. https://desertoasisautorepair.com/direct-injection-carbon-build-happens-prevent/#:~:text=As the miles are put,causes a carbon build-up.&text=The carbon build-up is,issue with their engine's performance. Regards Paul Link to comment Share on other sites More sharing options...
Pete Lewis Posted January 7, 2021 Report Share Posted January 7, 2021 change the engine oil on a modern at 5000miles HMMMMMMMMMMMMMMMMmmmmm!!!! petrol detergents are not letting the valves to be cleaned with direct injection HMMMmmmmm !!!! some of this is designed to put the fear of deep pockets into practice and collect the proceeds I might e a bit old but much of that should remain with the shoe repairer Pete Link to comment Share on other sites More sharing options...
Colin Lindsay Posted January 7, 2021 Report Share Posted January 7, 2021 Modern vehicles of today, especially those of the European manufacturers, have engineering unique to their designs. I'm glad he spotted that. We'd be able to work on them all if it wasn't for those pesky designers. Link to comment Share on other sites More sharing options...
NonMember Posted January 7, 2021 Report Share Posted January 7, 2021 Hang on... the petrol being sprayed directly into the cylinder means that it can't clean the carbon off the back of the valves... which got there from the fuel that... isn't being sprayed on the valves in the first place. As Pete rightly says, it's a consignment of geriatric shoemakers. Link to comment Share on other sites More sharing options...
Nick Jones Posted January 8, 2021 Report Share Posted January 8, 2021 20 hours ago, NonMember said: which got there from the fuel that... isn't being sprayed on the valves in the first place. Which got there from the EGR and breather systems.... and ran down the valve stem from leaky valve stem seals....... before being baked on. Valve backs noticeably cleaner on engines with port FI rather than carb. Never owned a DI petrol and not planning to. DI diesels can have ports almost blocked by carbon deposits from EGR....... I doubt DI petrol get quite this bad, but even a 1/4 as bad.......!! BTW pics are of a VAG 1.7SDI inlet. It ran better when cleaned out. Got to agree on those pesky designers though. Lots clear advances in maintenance hostility in recent years, especially in the VAG stables. Nick Link to comment Share on other sites More sharing options...
NonMember Posted January 8, 2021 Report Share Posted January 8, 2021 1 hour ago, Nick Jones said: Valve backs noticeably cleaner on engines with port FI rather than carb. Yes, because the vast majority of the crap on the backs of valves comes from over-fuelling, which carbs do lots and FI doesn't. Most GDI engines don't need EGR. The level of carbon you're seeing on that diesel engine is because it's been badly maintained and driven by a thug - it's been over-fuelled and smoky for quite some time. Link to comment Share on other sites More sharing options...
Nick Jones Posted January 9, 2021 Report Share Posted January 9, 2021 On 08/01/2021 at 17:27, NonMember said: been badly maintained and driven by a thug - it's been over-fuelled and smoky for quite some time. Quite possibly, came to us with 140k (and nearly solid oil). This at about 175k. Never smoked. Even when driven at continuously at full throttle, which is the only way anything “powered” by a VAG SDI engine will actually move (the s is for slow). Didn’t use any oil either. Did a similar exercise on my 5 pot Audi TDI when it had done about 175k. It was nearly as bad in spite of meticulous maintenance. EGR was disabled at the same time. Now on 335k and still clean so I conclude that EGR is the cause. It’s always comfortably passed the MoT emissions first run since then too, whereas before it needed all 6 attempts to squeak through..... Nick Link to comment Share on other sites More sharing options...
Ian Foster Posted January 10, 2021 Report Share Posted January 10, 2021 On 08/01/2021 at 15:51, Nick Jones said: Never owned a DI petrol and not planning to. My Mazda 6 MPS was direct injection and seemed to perform well even at high mileage (165k). Ian Link to comment Share on other sites More sharing options...
Chris A Posted January 10, 2021 Report Share Posted January 10, 2021 I'll come clear - I don't know what EGR stands for 😔 Link to comment Share on other sites More sharing options...
johny Posted January 10, 2021 Report Share Posted January 10, 2021 ooh ooh I know: exhaust gas recirculation... Think its, put hot exhaust gas back in somewhere to reduce emissions due to unburnt fuel, or something like that👍 Link to comment Share on other sites More sharing options...
Colin Lindsay Posted January 10, 2021 Report Share Posted January 10, 2021 It's a valve system that rechannels part of the exhaust gases back through the engine to burn any unused fuel that might otherwise come out through the exhaust and increase emissions. Fine in theory; in reality it just soots everything up and causes problems including eventual loss of power. I removed mine from the TD5 Discovery; very easy to do in most cars as you just remove the actual valve then blank off both ends of the pipe it sits in (some have a water pipe for cooling that you just reconnect end to end). It doesn't affect the MOT as diesel cars aren't tested for emissions (over here anyway, when they're actually being tested at all, that is) Link to comment Share on other sites More sharing options...
Chris A Posted January 10, 2021 Report Share Posted January 10, 2021 Thank you gentlemen. Je vais dormir moins bête, as the saying goes. Isn't one of the main points objectives of electronic fuel injection to stop there being too much fuel going in. I really should stick to simple things, low/ no tech . .so where is my dot to dot book? Link to comment Share on other sites More sharing options...
NonMember Posted January 10, 2021 Report Share Posted January 10, 2021 1 hour ago, Colin Lindsay said: rechannels part of the exhaust gases back through the engine to burn any unused fuel Actually it has nothing to do with burning unburnt fuel. Its purpose differs almost entirely between diesel and petrol, even though the mechanism is very similar. On a diesel engine, the EGR serves to slow the burn of the injected fuel, particularly at high boost, which reduces the temperature and hence reduces NOx emissions. However, the consequence of lower temperatures is also that you run less efficiently and produce more black smoke. As a side note, the famous VW emissions scandal centred around them actually using less EGR in the real world, and hence getting more NOx (but also more fuel economy) than the test implied. On a petrol engine, EGR is used to increase cylinder pressure when running at very light load. The air/fuel mix must be stoichiometric so you can't add extra air, which means you run into both "pumping losses" and combustion (pressure) limits. Adding some inert (exhaust) gas allows you to get round both of these and run more efficiently, giving better economy and emissions. Link to comment Share on other sites More sharing options...
68vitesse Posted January 10, 2021 Author Report Share Posted January 10, 2021 Out in Vitesse today for shopping, car started ok without misfire so must have been plugs. Any recommendations for plugs apart from NGK. Regards Paul Link to comment Share on other sites More sharing options...
Iain T Posted January 10, 2021 Report Share Posted January 10, 2021 Bosch WR78 are good, bought mine from Greenspark Plug. Iain Link to comment Share on other sites More sharing options...
Guest Posted January 10, 2021 Report Share Posted January 10, 2021 Hello Paul, NGK is a decent plug and TBH you will always get a duff plug at some stage - either on initial installation or after some use. Purchasing from reputable companies such as Green Spark Company is at least a step forward in the right direction to ensure a quality product. I've used and still use NGK BP6ES on all my past & present classics without issue; I'm sure my day will come !! I know Nick recommends Bosch WR78 which are multi pronged. Of note and IIRC the WR78X has a wider electrode gap and is probably unsuitable for cars that use BP6ES whereas the WR78 is suitable - I'm sure Nick can confirm that either way. Champion do have a somewhat chequered history with many users reporting that their performance is inconsistent. I cannot really quote on that as I have not used Champion plugs since the mid-80's. It's easy to be sweeping and chuck the baby out with the bathwater. I always give the threads of my plugs the minutest smear of oil to prevent the plugs binding - never had any running issues doing that and nor when removing them. Regards. Richard. Link to comment Share on other sites More sharing options...
Guest Posted January 10, 2021 Report Share Posted January 10, 2021 4 minutes ago, Iain T said: Bosch WR78 are good, bought mine from Greenspark Plug. Thanks Ian, perfectly timed !! Link to comment Share on other sites More sharing options...
Pete Lewis Posted January 10, 2021 Report Share Posted January 10, 2021 https://www.gsparkplug.com/1x-bosch-special-spark-plug-wr78.html Pete Link to comment Share on other sites More sharing options...
68vitesse Posted January 10, 2021 Author Report Share Posted January 10, 2021 Thanks for the replies. Regards Paul Link to comment Share on other sites More sharing options...
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