Hi guys, Wondering if you can help. I was driving back home when I heard a massive bang..... sounded like a big misfire. Now its running rough and now cylinder 4 isn't firing (pulled coil connector and no change) So far I have moved coil pack. Issue remains at cylinder 4 I am getting fuel because I am getting backfires and I can hear the injector clicking. Could I have damaged the spark plug? Car has New Injectors Series 2 PTU New Coil Pack connectors Any ideas? Cheers Chris
Take the plug out. Check for oil. Clean refit. See if issue still occurs. Then try it in another cylinder and see if it follows then.
Just wondering if there is anyway to check the coil pack connector with a multi meter while the engine is running? I.e take the plug off and meter it somehow. I have replaced the connector with a new one but I don't think I am getting any spark and I think its either the spark plug or the wiring to the coil pack. Its too dark to change the spark plug tonight so I am just getting some idea's for tomorrow problem solving. Cheers Chris
easy way to check the coil pack is swap it to a known running cylinder. you can check the wiring by swapping it to the next cylinder for long enough to see if it makes a diffrerence as well (you should be able to hear the engine change revs/note). My bet is also on a dead plug, although you may have an injector thats failed - rule out your plugs first. Finally IMO if you have iridium plugs installed and its failed there is not a lot that can be done. Get some replacements if you think its died. You can also test the coil pack with the plug out by earthing the plug on the engine and turning the car over and checking for spark- disable your fuel pump first. If these things are beyond you I am sure there is a local who can help.
massive bang - something broke (or you had a misfire, but why would no 4 not fire ?) What's the compression on no 4 ? Did you bend a valve ?
You may have had the end blown off the spark plug. Suggest you pull it asap and check. Dont run the engine if you can avoid it
This looks like the car I saw in Enoggera yesterday, where in Brisbane do you live? I may be able to help!
Hi Martin, Thanks for the kind offer, i'll let you know if I need a hand. I am based in West End. I wasn't in Enoggera yesterday sorry. Anyways first things first I am going to pull the spark plug and inspect. Will report back with the findings Cheers Chris
Hey guys, I have taken the spark plug out and this is what it looks like The one on the left is from the non firing cylinder and the one on the right is from a firing cylinder. I moved the spark plug from cylinder 4 to 2 and cylinder 4 still doesn't fire. I have put a screwdriver onto the injector and its clicking away. So moved coilpack - Problems stays at cylinder 4 Changed spark plug - Problem stays at cylinder 4 Checked connectors - New coil pack connectors. Another new thing is the car is hard to start.... Any ideas? Cheers Chris
Right just checked the connector and I am getting 12 volts to the centre pin. Just incase this helps. Chris
Check your battery, probably hard to start from all the start - stop of the testing. put it on a charger and give a good charge so you dont end up with a dead battery thread.
Right I think the worse has happened. Just to re-cap and thinking about it a couple of days later this is what happened. Did a plenum pull and it all went wrong lol!!! Then I rebuilt the car with new injectors, new fuel lines, new coil pack connectors, new vacuum lines, delete aiv and new plenum gasket etc. So the car ran fine for 24 hours, drove about 100 kms no problems. Was giving it a little gas up to 4.5k in second and when I came off the gas I heard a loud metallic sound and felt a knock around the gear knob I thought it was a backfire on overrun. Ever since that incident the car has been running on 5 cylinders. Cylinder 4 is not playing the game so diagnosis was as followed. New coil pack connector - 12v on middle pin, 14v when car running. Moved coil pack - 4 still not firing Moved Spark Plug - 4 still not firing Listened to injector with screwdriver - Clicking Ohm tested injector - 12.8ohms (All 6 have been flow tested and cleaned) Visual of cylinder 4 spark plug sparking against plenum So I have fuel, spark and air in cylinder 4 so the only thing it could be is no compression!!!! Don't have a compression tester to hand so.. I put the spark plug in a couple of threads to hear if there was any compression hissing past the injector and it was a little weak. I think I have bent a valve or something has happened in the cylinder. There is no water in the oil and there is no smoke from the exhaust. Looks like a rebuild might be in order Chris
Hate to say it but sounds like Chrispy is on the mark. and looks like you have done nearly all you can to check for alternatives. never a great thing to find issues like this.
Try no to start it anymore, until you have identified the problem for sure, dont want to make things even worse, especially if there is something loose or sheared or hitting in the valves etc. Hope it turns out to be nothing really really major and you get it back on the road soon. Always makes me feel somewhat sad whenever bad news happens to a fellow Z'der Good luck and best wishes with it, hope it goes well for you in fixing it
A valve could have seized and or bent , spring could have broken ( long shot ) causing valve to drop also . I would get compression test done before you pull anything off .
Cheers for all the information. Seems something has broken. I definitely heard a metallic ping noise when it went and it was a strange when I felt a knock sound around the gearbox. Going to get the compression test done tonight and go from there..... I suppose its heads off time to inspect the damage. Will keep you guys updated. Cheers Chris
