i dont know what else to try iv'e replaced all 6 plugs (ngk platinum),bought and tried another coil pack on each plug to try to find a possible faulty one but still plays up. i can be driving along fine then it goes to 5 and after a while it rights itself again. frustrating to say the least! can anyone shed some light on the problem and offer up an answer? much obliged.

Vibration on a PTU connector?

thanx i'll check that out

Intermitent missfire pionts towards the PTU.Try a cleanup on each connector.I had the same thing on mine and discovered one of mine had managed to come completely undone causing the missfire.

could be! should i use wd40 or just a clean cloth?

Erm try some WD40 and clean any corrosion or dirt off.

thanx for your help mate

Did it work?

giving the injector connectors a good cleaning will probably help also, since these are probably full with the "green stuff" .

i'm at work at the mo. i'll try when i get home

Let us know how you get on.

it appears that the left rear coilpack push on lead is not working. i have run the engine and pulled that lead off and there is no difference. it is a short lead and obviously goes into the loom. could it be a frayed or broken wire that connects now and again under vibration like you mentioned?

I would imagine so,though normally its the actual connector

Well if it comes and goes i would imagine its a loose connection somewhere,finding it is your next task!.so have you have pretty much eliminated a coilpack fault by swopping them over then?

I HATE PTUs!

yes i have systematicaly tried all 6 . i just tried taking the coilpack out and plugging a spare plug in and earthing it to see if it is sparking, and it is. this leads me to believe that maybe the problem is on the fuel side. maybe a dirty injector. trouble is i'm not exactly sure where they are. i haven't got a manual to check it out, could you describe where the injector is for that pot?

The injectors are located under the throttle cover mate,try that.

cracked it !! probably the worst one to get to but just moving it ,the engine picked up,just to make sure it wasn't a fluke i moved it about and it dropped off and picked up again.i will have a better look over the weekend and clear it up once and for all. many thanks for all the advice and after all a problem shared is a problem solved!!

cheers kamikaze

U arent the only one out in the cold.Im playing with the connectors at the moment as well.One is completely shot!

i know at least two of the connectors on the top of the coil packs are broke i think it must be the heat that does it , they become very brittle

heat is main cause of the brittleness.

Hope you get problem sorted.

can you buy new connectors for them or do they come as part of the loom?

look on Ebay for them-cant rememeber how much though.Just solder on and you are away.Thinking of changing mine for a new series 2 loom.

like these

http://cgi.ebay.com/ebaymotors/6-New-Nissan-Coil-Pack-connectors-300z-1990-1996-300zx_W0QQcmdZViewItemQQcategoryZ46098QQitemZ8045182526QQrdZ1QQsspagenameZWD2V

 

I know MJP do them as well

you could be on to something there i think i'll change them all in due course

hello mark,

 

about 2 months ago my car was firing on 5.

 

it wasn't the ptu (swapped with another)

it wasn't the coilpacks (interchanged)

it wasn't the coilpack or injector connectors even though they were green as the hulk before i cleaned them with an electrical solvent-amberclense/FE10 :mad:

it wasn't the spark plugs either.

 

unfortunately for me my no. 4 injector failed so it was over to the zen garage, plenum off, new gaskets, new bypass pipes, new injector. running sweet now :)

 

it cost me a fair amount of dosh mainly for labour as i didn't fancy taking the plenum off myself and then realising i had no way of getting the new seals/pipes/gaskets that would and did break.

 

i hope it isn't the injector as this is the most expensive outcome. but don't count it out like i did!

 

hth

mjp ? is that mike in brentwood essex?