:mad:Bit of a problem hope somone can help here goes, last week end I changed the oil,oil filter and spark plugs my zed is a tt jdm so I got a set of PFR6B-11C plugs the plugs I took out were PFR6B-11 which I thought were for a NA zed anyway after fitting the new plugs the zed started to hesitate if you accelerated hard took all the plugs out checked them over and put them in again but still no better so today I put the old plugs back in and the zed drives perfect. Can someone tell me if I got the wrong plugs or are they the right plugs but could be faulty all advice welcome

Should have got the PFR6B-11B, but the 'C' should work.

 

Your Z on stock boost?

sounds more like your coilpack connectors need cleaning or are not seated right

Doesn't explain why they worked with the old plugs after the 'C's didn't appear to fire correctly.

The 11-C's are in fact Nissan standard plugs mate so should have worked perfectly well for you. The 11b's Si mentioned are a slightly improved plug and aslo would have done the job.

 

So, can only deduce that 1 of the plugs is faulty, however even stranger is the plugs it currently runs, erm it shouldn't.

Strange!

smithy

Should have got the PFR6B-11B, but the 'C' should work.

 

Your Z on stock boost?

 

totaly stock thats why I got the C plug is the PFR6B-11C FOR STOCK?

Should be ok then. Do you have a different chip?

The 11-C's are in fact Nissan standard plugs mate so should have worked perfectly well for you. The 11b's Si mentioned are a slightly improved plug and aslo would have done the job.

 

So, can only deduce that 1 of the plugs is faulty, however even stranger is the plugs it currently runs, erm it shouldn't.

Strange!

smithy

 

Whats the quickest way to find a faulty plug, change a plug in one at a time to find it?

Should be ok then. Do you have a different chip?

 

nope , at least not that I know of

sounds more like your coilpack connectors need cleaning or are not seated right

 

coil packs are fine with old plugs

So the 11c are the correct plugs for a jdm tt so there must be a fault with one or more of mine

Correct and i guess the only way to find out, is to take a chance on 1 plug at a time fitted to the car until it develops the same fault again.

smithy

Correct and i guess the only way to find out, is to take a chance on 1 plug at a time fitted to the car until it develops the same fault again.

smithy

 

Will try that tomorrow Smithy and can you confirm the plug gap

or you good put the new plugs in and disconnect the coilpack connectors one by one, and listen for a change in sound, if one doesn't work you will be running on 5 cylinders

Only does it on boost/acceleration by the sounds of it. Not easy to do on idle.

or you good put the new plugs in and disconnect the coilpack connectors one by one, and listen for a change in sound, if one doesn't work you will be running on 5 cylinders

 

with all new spark plugs in (11c) the zed runs perfect it only starts to hesitate under heavy acceleration

did you set the gaps on the new plugs?? or did you just put them straight in? i had to remove mind and set the gap it was way out. think the gap was 1.1mm from memory

did you set the gaps on the new plugs?? or did you just put them straight in? i had to remove mind and set the gap it was way out. think the gap was 1.1mm from memory

 

yes 1.1 is what I gaped them at as they came with a larger gap

hmm very strange, out of ideas sorry mate

hmm very strange, out of ideas sorry mate

 

will test for faulty plug tomorrow

yes 1.1 is what I gaped them at as they came with a larger gap

 

 

There is the clue to your problem the PFR6B-11C plug comes preset to the correct gap ( the last two digits of the part number) if you changed them you either made a mistake ( sorry if that sounds rude) and closed them down too much or they where damaged in transit, in nearly 10 years of fitting that very same plug type I have never had to adjust any ever.

 

Also for general info

PFR6B-11C plug is standard plug for UK spec zeds

PFR6B-11 plug is for standard Jap spec zeds ( twin and non turbo )

PFR6B-11B plug is standard US plug

 

When imported into the UK the Jap spec plugs will work ok but it is advisable to change them to the UK spec ones as these work best with UK fuel and running conditions.

 

The US plug is often used as an "upgrade" for zeds running extra power and is deemed safer by many owners and sellers, I for one have not seen any clear evidence of this either way so cannot comment except to say the US running conditions and fuel is very different to the UK and it may be just be good luck they work out that way and not by design.

 

Iridium plugs Avoid at all costs, hopelessly inefficient in the zed engine, designed to work with smaller high reving engines, they cause tick over issues and have hopless self cleaning properties, now this I have seen many times. It is often possible to detect from the sound and nature of an uneven tickover without even lifting the bonnet to know iridium plugs are fitted.

 

UK spec plugs are the best ones in my opinion and never give problems in normal service so to have a problem when first fitted is either a coincidence of disturbing connections to injectors/ coil packs etc. or you adjusted the plugs wrongly.

 

Good luck at sorting it out matey.

 

Jeff TT

 

 

 

Jeff TT

Edited June 14, 200916 yr by JeffTT

Jeff your advice is so good you post it twice:bow: hopfully will get to the bottom of it today and get back with results

Jeff your advice is so good you post it twice:bow:

 

Oh erm dont know what happened there? :headvswal

 

Jeff TT

Jeff your advice is so good you post it twice:bow:..................

 

Oh erm dont know what happened there? :headvswal

 

Jeff TT

 

Fixed!

 

And sound advice as always Jeff........

 

........I happen to have iridium plugs in my Z - I reckon I'll take Jeff's advice and go back to the standard ones;)

 

Richard:cool:

:hyper: Think I found the bugger the third plug I fitted seamed to unsettel the engine under hard aceleration took it out and went through the rest which were ok so ended up sticking one of the PFR6B-11 in untill I get another one. I could nave damaged the bad plug setting the gap which were all way over 1.1 but surprised the zed ran so well with the NA plugs:confused: Hope this is it all sorted now thanks to all out there with all the advice and my next plug change I think I will try the PFR6B-11B to compare them with the 11C

but surprised the zed ran so well with the NA plugs:confused: Hope this is it all sorted now thanks to all out there

 

Just to clear that up you had Jap spec plugs they are standard fit for both twin turbo and non turbo, almost all imports will have them fitted, just a good idea to fit UK spec ones to suit UK running conditions.

 

 

 

Originally Posted by Richardsmith

 

Fixed!

And sound advice as always Jeff........

 

Thanks matey

 

Jeff TT