hi all , wierd thing happend today , started car in preperation to warm it up before journey home, had to turn it of to lock gate , turned it back on missfire constant never changing, spoke to ryan ,, poss , c.a.s , ,ptu coil connector , injector conector, etc, have narrowed it down to front right conector plug , as in when i remove this it makes no difference to engine tick over ,,

 

cleaned connector and injector conector, also swapped rubber bit thats plug onto spark plug and coil packs connect to , no difference , im guessing only things left to try is spark plug or ptu , its series 1 ptu , any ideas??

bump

Try swapping the coil packs around to see if the missfire moves.

hi have done this .no different same missfire at same place ,first right hand cylinder, going to try changing spark plug today to see if it moves , if it doesnt them im miffed , ?

ok checked spark plugs ,, the offending , missfire cylinder is stink of unburnt feul so guessing the coil pack connector or ptu ,, but connector is clean , just about to put spark plug in other cylinder ie change its position to see if problem moves, any input would help guys, have read all post on missfires but no answers as to how it was solved ,

not the spark plug !! more digging can only be connector , or loom, as dont have tester to check it and dont fancy licking end of it either, ,,

ok buddy if the coil is ok and the spark plug is ok then all that is left is either the injector is faulty the compression is low in that cylinder, or the siganls for the coil or injectors is missing. first off remove faulty cylinder spark plug and check if is it wet (withfuel), if it is soaked then as you mentioned the fault is more likely to lie with the spark side or with compression. if you can carry out a compression or cylinder leakage test then i would advice it because if the injector is working and there is no spark then the fuel that is not being burnt can wash the lubrication off the bore and wear the engine out. is there excessive white smoke out of one of the echaust as this could be the unburnt fuel. if the find for sure that the fuel system is ok then i advice you to carry out a resistance or volt drop test on the wiring to the coil. it that is ok then i'd use an (if i can spell it right) oscilloscope to check the signal on a graph to make sure the engine control unit is telling that cylinder to fire.

 

a more lam test you could do is remove coil and spark plug. push the spark plug into the coil as it would be normally make sure the coil connector is plugged in and clamp the metal part of the plug (not the electrode) to a metal part of the car and crank it over you should be able to visuably see if the ignition system is working or not.

 

hope that helps :D

 

oh this is Cap-N-Burn. am using girlfriends comp so thats why it says Taz

cheers taz,, have done as said ,, definatley unburnt fuel ,, no spark for sure , not sure if its coil pack conector or ptu, or loom , as yet,, but am driving to see the doc tommorow fingers crossed its not low compression in that cylinder as me zed days would be over !! the faith is strong but the wallet couldnt take a hit like this with the probs im having this year , mainly with the daily driver, its had new disks new pads new tyres new clutch, new diesel pump, and thats the only this year, the zed on the other hand hasnt let me down once untill now,,, ive only ever had minor probs with zed which ive cured with help from guys and gals on here there a great bunch ,

 

 

no you recently bought a zed two , so hope to see more of you cheers bud ,will keep all of you posted !!!! but no this can be fixed its just a qestion of how much , ,

ah am on my own account now. np buddy hope it all goes good for ya. oh by the way if you are gunna drive the car like that (not recommended) then i'd disconnect the injector for that cylinder to help prevent bore wash. also if you have found that the cylinder in question has no spark then it is likely that this is causing ya problem and the compressions are more than likely ok, but once fixed i'd pump a tiny amount of oil in the cylinder to help relubricate the bore and prevent damage. you could check supplies to the coil. there should be 3 wire (not sure what the colours are) one should be 12v with ignition on the other should be a perminent earth and the last one will be a signal wire from the ECM (engine control module) if you have a volt meter you could test these. now i work on nissans day in day out and i don't want to get ya hopes up but 90% of the time when i get a fault of this discription and i find coils plugs injectors and compressions are ok then the fault is almost always with a loose connection at the ECM or other connectors or there is a broken wire only 10% of vehicles like this end up being ECM, especially on old cars like this. hope this helps :D

 

Cap N Burn

hi just to let you no it turns out after ryans very helpfull work it was the ptu that was faulty, , have many more probs , so zed is off the road for a long while , so see you all again soon enough , two months , cheers for all your help ,

no problem mate am here to help :D