spectron Posted March 11, 2019 Share Posted March 11, 2019 Hi all, as the title, I'm starting to get an occasional misfire when the car gets hot and do get the EML flashing intermittently. The odd thing is though, when we had a scan this weekend it's not storing any fault codes at all? Does anyone know of an issue that would cause the EML to flash for misfire but not store a code? Cheers Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted March 11, 2019 Share Posted March 11, 2019 Are you sure that it is the EML that is flashing and not the traction/anti skid? Quote Link to comment Share on other sites More sharing options...
spectron Posted March 11, 2019 Author Share Posted March 11, 2019 21 minutes ago, ZMANALEX said: Are you sure that it is the EML that is flashing and not the traction/anti skid? Yes, it's definitely the EML, I've had it light up before at higher revs before I changed the spark plugs. It flashes at a constant rate for a good 10 seconds whilst the engine seems to misfire then goes off again. Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted March 11, 2019 Share Posted March 11, 2019 Without a code you are guessing I am afraid. Plugs, coils, cam position sensor, injector, etc etc. are stuff that I would be looking at. Perhaps might be a plan to let it develop until it stores a code. Quote Link to comment Share on other sites More sharing options...
spectron Posted March 11, 2019 Author Share Posted March 11, 2019 35 minutes ago, ZMANALEX said: Perhaps might be a plan to let it develop until it stores a code. Yes, those were my thoughts cheers Quote Link to comment Share on other sites More sharing options...
Jay84 Posted March 11, 2019 Share Posted March 11, 2019 In my experience on customers cars (non zed) heat caused misfire usually points to coil packs breaking down rather than plugs. If you have a scanner with a misfire counter it may help, especially as they're individual coils on these, replacing all 6 could be costly and not necessary. Quote Link to comment Share on other sites More sharing options...
Chrissaxon Posted March 11, 2019 Share Posted March 11, 2019 Was the fault there before you changed the spark plugs? It could be coil pack breaking down . You will find out when you take out the spark plugs. If it's faulty . Quote Link to comment Share on other sites More sharing options...
spectron Posted March 11, 2019 Author Share Posted March 11, 2019 58 minutes ago, Chrissaxon said: Was the fault there before you changed the spark plugs? It could be coil pack breaking down . You will find out when you take out the spark plugs. If it's faulty . No the misfire under these particular conditions manifested about 1000 miles after the spark plugs were changed. When I bought the car, the previous owner had obviously neglected the plugs because after about 4 weeks of ownership I started to get a random misfire at high revs, which was sorted by changing the spark plugs. I'm hoping that by previously neglecting the plugs and causing them to break down, it put more stress on the coils which is why I'm now getting the issues I am. At least then it's any easy fix to diagnose and sort. The good news is that I do now have a permanent EML so a code has been logged so just need to get my reader on it tomorrow. Quote Link to comment Share on other sites More sharing options...
Kieran O'Quick Posted March 11, 2019 Share Posted March 11, 2019 I chased this problem for ages. The code reader kept saying random misfire. If it's misfiring when hot you can find the offending coil by cooling them, I think its something electronic people do routinely? I got some freeze spray, waited till I got the misfire and sprayed the tops of the coils. P3 cooled down and the engine purred. The spray evaporated off and it ran rough again..... Quote Link to comment Share on other sites More sharing options...
spectron Posted March 12, 2019 Author Share Posted March 12, 2019 10 hours ago, Kieran O'Quick said: I got some freeze spray, waited till I got the misfire and sprayed the tops of the coils. P3 cooled down and the engine purred. The spray evaporated off and it ran rough again..... Good option; I've got some in the garage but I'm doing nothing in this weather...! Quote Link to comment Share on other sites More sharing options...
spectron Posted March 13, 2019 Author Share Posted March 13, 2019 Just as a final update, cylinder 5 had the misfire so replaced the coil and all is now good. Only issue is the dreaded oil in the recess so it looks like I'm heading for a rocker cover gasket set replacement to stop it happening again..... Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted March 13, 2019 Share Posted March 13, 2019 Glad to hear that you have sorted your misfire: Rocker Cover sets here: Quote Link to comment Share on other sites More sharing options...
spectron Posted March 13, 2019 Author Share Posted March 13, 2019 Pm sent... Quote Link to comment Share on other sites More sharing options...
ZMANALEX Posted March 13, 2019 Share Posted March 13, 2019 PM received and replied to: Quote Link to comment Share on other sites More sharing options...
Willsy1980 Posted May 10, 2019 Share Posted May 10, 2019 Sorry to jump on this one, but getting a similar issue, drives fine upto 70ish at 80 or above missfires. More noticeable up hill. EML flashes for 10 seconds then stopped, logged P0300 (random missfire on one or more) and P0303 (Missfire on cyl 3) Ordered plugs to fit but is it more possible its the coil pack ? Quote Link to comment Share on other sites More sharing options...
Kieran O'Quick Posted May 10, 2019 Share Posted May 10, 2019 Its a nice bonus that it logged the cylinder. Phew. The coil would be the next thing to swap if the new spark plug doesn't fix it, I'd say. Quote Link to comment Share on other sites More sharing options...
Willsy1980 Posted May 11, 2019 Share Posted May 11, 2019 (edited) 6 Plugs done, 3 hours. First time i've stripped anything off so don't think it was too bad. Seems to run better than it ever has so far, need a long motorway run to see if the issue returns now... Number 6 is a right arse to swap. One thing that did 'happen' P1136 quick google 'Potentially fried ECU' Panic time. On closer inspection I didn't reconnect the cam sensor near the airbox... Safe to say, they were knackered.. Update: Still misses under load at 80 in 5th/6th Coils next I guess.... Edited May 11, 2019 by Willsy1980 Quote Link to comment Share on other sites More sharing options...
Kieran O'Quick Posted May 11, 2019 Share Posted May 11, 2019 At least number 3 is the easiest coil to swap... Quote Link to comment Share on other sites More sharing options...
Willsy1980 Posted May 11, 2019 Share Posted May 11, 2019 yeah but ill do all 6, no point pissing about I don't think. Quote Link to comment Share on other sites More sharing options...
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