Puffwagon Puff Gold Donating Members 15,831 Member For: 9y 9m 11d Gender: Male Location: South Australia Posted 12/02/17 10:57 AM Share Posted 12/02/17 10:57 AM On 12/7/2016 at 1:37 PM, rollex said: Now it goes lean at idle indicating a miss fire. How lean? I know there was a lot of talk about coils but lean at idle points to an injector not injectoring. To confirm what I already knew I literally just went outside, started my car up and watched the afr go from 14.0:1 up to 16.8:1 when I pulled an injector plug. If the fuel kept going and the spark didn't then there would be excess fuel in the mixture and it would go rich. I cbf pulling my car apart to confirm but some things are just common sense. Things I can think of doing off the top of my head right now (I've just had 3 beers so forgive me if I forget something or many things) are; Swap injectors around to determine if it is a faulty injector, Last I checked injectors have a constant 12V feed (give or take) and pulse the ground so check the the faulty cylinder has power when it's malfunctioning (multimeter), Check that the ground is pulsing with the injector still plugged in (test/noid light or similar), Check the pins in the plug aren't too wide, they can become bent and not provide a sound connection, Check that the pins haven't been pulled out of the plug, Those last two suggestions are tantamount to checking the wiring so check the wires for splits, cracks and breaks and also check the plugs in the loom for proper mating, corrosion and of course pin connection. The only strange thing is that the problem disappeared briefly when you replaced the plugs. Anyway as we all know there is only so much we can help over the internet and we are relying on your diagnosis and interpretation of the issue which may not be correct as well, no offense. Good luck mate, hope this helps and if it is indeed a fuel issue, which it points to, then you have some ideas to keep you going. Link to comment Share on other sites More sharing options...
rollex Member 683 Member For: 10y 5m 1d Gender: Male Location: Australia Posted 12/02/17 11:06 AM Author Share Posted 12/02/17 11:06 AM (edited) 8 minutes ago, Puffwagon said: If the fuel kept going and the spark didn't then there would be excess fuel in the mixture and it would go rich. I cbf pulling my car apart to confirm but some things are just common sense. An o2 sensor measures oxygen, a misfire regardless of reason will read lean as you have excess unburnt oxygen in the exhaust. Eg if I unplug all my coils it will read 20:1 or whatever the max lean condition is as none of the oxygen is being burnt. If I unplug injectors and the coils it will still read 20:1 despite there being far less fuel in the exhaust. I will try the things you mentioned though, swapping injectors is a pain but it's getting to that point now... Edited 12/02/17 11:07 AM by rollex Link to comment Share on other sites More sharing options...
Puffwagon Puff Gold Donating Members 15,831 Member For: 9y 9m 11d Gender: Male Location: South Australia Posted 12/02/17 11:13 AM Share Posted 12/02/17 11:13 AM Swap the injectors around first mate. Link to comment Share on other sites More sharing options...
Puffwagon Puff Gold Donating Members 15,831 Member For: 9y 9m 11d Gender: Male Location: South Australia Posted 12/02/17 11:35 AM Share Posted 12/02/17 11:35 AM Lol I just checked what happens when you pull a coil out and you're right, it went leaner. Pulling the injector made it go 2.8 leaner and pulling the coil made it go about 0.7 leaner. There would have been some slight interference from the narrowband sensor in both cases (I pulled and checked as quick as I could several times) and the car was cold on both occasions. Obviously I could tune it to have no o2 interference but that's not the issue we are looking to solve. Food for thought. Link to comment Share on other sites More sharing options...
rollex Member 683 Member For: 10y 5m 1d Gender: Male Location: Australia Posted 13/02/17 06:39 AM Author Share Posted 13/02/17 06:39 AM Ok I don't want to jinx it but think I fixed the problem. Above the coilpacks on the head cover there are rubber stoppers that press down on the coil and make sure it is tight. Cyl 6,5 and 4 were all missing them. I cut up some hose and stuck it in the same place and the car has survived about an hour without dropping a cylinder. Wish me luck! 1 Link to comment Share on other sites More sharing options...
Puffwagon Puff Gold Donating Members 15,831 Member For: 9y 9m 11d Gender: Male Location: South Australia Posted 13/02/17 06:45 AM Share Posted 13/02/17 06:45 AM Good luck! When I pulled my coil out last night it was jumping a large gap and was firing the plug when it was just sitting in there loosely. Link to comment Share on other sites More sharing options...
rollex Member 683 Member For: 10y 5m 1d Gender: Male Location: Australia Posted 13/02/17 10:14 AM Author Share Posted 13/02/17 10:14 AM Yeah it still fired when I did the same but when listening to the exhaust note it was noticeably rougher with ~3 of the coils pulled halfway out. I'm guessing when hot it turns to sh*t as it wasn't missing completely when I played around with it. Tonight is the first time I've gone for a drive lately without it dropping a cylinder. Link to comment Share on other sites More sharing options...
Puffwagon Puff Gold Donating Members 15,831 Member For: 9y 9m 11d Gender: Male Location: South Australia Posted 13/02/17 10:28 AM Share Posted 13/02/17 10:28 AM Hopefully that's fixed it then. Link to comment Share on other sites More sharing options...
rollex Member 683 Member For: 10y 5m 1d Gender: Male Location: Australia Posted 14/02/17 12:17 AM Author Share Posted 14/02/17 12:17 AM (edited) Was purring like a kitten on the way to work today. Feels like a new car. Now I just need to figure out the bloody clutch. Edited 14/02/17 12:17 AM by rollex Link to comment Share on other sites More sharing options...
ScottyB New Member 5 Member For: 10y 2m 6d Posted 14/02/17 09:25 PM Share Posted 14/02/17 09:25 PM Awesome. You don't have a pic of these rubber stoppers do ya? I've got a similar problem with my n/a. Link to comment Share on other sites More sharing options...
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