XPT 673 Posted October 26, 2017 A bit of a strange problem. My (manual) AU ute misses under load mainly when it's warm. It usually runs ok in the morning, you can give it full throttle and it pulls cleanly through the gear. Sometimes it runs like shit from the getgo, this morning it ran perfectly. At times it can run fine initially then after 15-20 minutes of driving it start playing up again. It doesn't miss at idle, or under light throttle. When it's playing up and you apply say 1/4 throttle or less it pulls through the gear ok. I've replaced the leads with genuine bosch ones still the same symptoms. I know coil packs are a very common problem but I would have thought they're either fucked or not, not intermittent. They're not expensive, I just dont want to get under a car I don't particularly like to do a shit job only to not fix the problem. Ideas anyone? Share this post Link to post Share on other sites
bear351c 10,270 Posted October 26, 2017 Hmmm...... would have said coil packs. Maybe Ignition module.? Fuel filter been changed? 1 XPT reacted to this Share this post Link to post Share on other sites
deankxf 20,279 Posted October 26, 2017 i was always told coils either work or they don't.. however i've had over the last 25 yrs at least 5 counts (mates cars included) where they will play up when warm etc.. so i'd agree with Bear.. coil pack (or plugs) but i haven't ever had any experience with coil pack cars..but would assume the same applies. it's not the only thing it could be, but just don't rule out the coils as a works or doesn't reason.. 2 XPT and Outback Jack reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted October 27, 2017 I had an AU come in with a very slight roughness at idle, pulled out the plugs and found all of them had their electrodes melted into little balls (instead of a sharp needle point) This was at 70,000 km, and iridiums are meant to go 150,000.I have shitloads of factory BA/BF plugs here if they are a suitable substitute. I can send up a set if you like.Sent from my CPH1607 using Tapatalk 1 Outback Jack reacted to this Share this post Link to post Share on other sites
Outback Jack 6,352 Posted October 27, 2017 Can happen from running shit fuel in a 10/11:1 motor.AUs like decent fuel.Not like the XG at 8.5:1 ..... run on lamp oil.... lolSent from my GT-S7583T using Tapatalk Share this post Link to post Share on other sites
XPT 673 Posted October 27, 2017 4 hours ago, gerg said: I had an AU come in with a very slight roughness at idle, pulled out the plugs and found all of them had their electrodes melted into little balls (instead of a sharp needle point) This was at 70,000 km, and iridiums are meant to go 150,000. I have shitloads of factory BA/BF plugs here if they are a suitable substitute. I can send up a set if you like. Sent from my CPH1607 using Tapatalk I forgot to say I did the plugs when I got it. I think I've only done about 8k in it. I've run it on e10 or 98, still plays up. It's definitely only on one or two cylinders. At $100 I'll just do the coil packs. It's more the annoyance of having to do it than anything. Just wanted check around the traps to see if there's any other ideas. Thanks for the input guys, I'll let you know how it goes. Share this post Link to post Share on other sites
Thom 6,650 Posted October 27, 2017 It you have a bunch of extensions and pull the airbox out you can change the coil pack from the top, easier than trying to do it reaching over the engine mount 1 XPT reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted October 27, 2017 Yeah the reach-around is not a pleasant experienceSent from my CPH1607 using Tapatalk 2 Thom and XPT reacted to this Share this post Link to post Share on other sites
SPArKy_Dave 8,869 Posted October 28, 2017 Also consider a sticking injector. In my experience, a spark miss in an OHC falcon, usually gives a decent kick as it comes and goes, whereas a fuel miss can be subtle. Note the manner in which it starts, after a run. If it starts too easy/too quickly, that usually points to leaking/stuck open injectors. Share this post Link to post Share on other sites
Outback Jack 6,352 Posted October 28, 2017 +1 with Dave on fuel.Plugs melting and too hot... not enough or shit fuel. Sounds like fuel filter, fpr or fuel pump. If was one injector would not melt all plugs. Jack. Sent from my GT-S7583T using Tapatalk Share this post Link to post Share on other sites
XPT 673 Posted October 30, 2017 Yep it was the coil pack. Thanks for the tip Thom it was piss easy to do it from the top using a few extensions and removing the airbox apart from constantly burning myself on the coolant pipe lol. I had to get it done before it started pissing down. So no time to let it cool. Thanks a lot for your input guys. Cheers 5 Valvebouncer, Thom, deankxf and 2 others reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted October 30, 2017 Burnout vid or we don't believe youSent from my CPH1607 using Tapatalk 2 Outback Jack and XPT reacted to this Share this post Link to post Share on other sites
XPT 673 Posted October 31, 2017 17 hours ago, gerg said: Burnout vid or we don't believe you Sent from my CPH1607 using Tapatalk It might only manage a clutch burnout 1 gerg reacted to this Share this post Link to post Share on other sites
gerg 10,871 Posted October 31, 2017 It might only manage a clutch burnout Smoke is smoke, right?Sent from my CPH1607 using Tapatalk 1 XPT reacted to this Share this post Link to post Share on other sites