My Brothers Pulser started to miss fire yesterday,
But before hand had been running fine all week, and last time it was booted was 2 fridays ago.

So he removed the plugs, and the tip was missing on cyclinder 1 plug

And we know its running 11.8 - 12.0 :1 AFR, as he's got a wideband fitted, and he sed he was watching it last time he gave it some wellie.
And there's NO DET at all.

He's running HKS plugs, which he's never dropped or damaged them in any way.


Has anyone had similar problem?

All i can put it down to is a faulty plug, or injector is failing.

 

wrong temp plugs

 

How does your brother know that 12.0 is a safe AFR on his engine?
What EGT does that result in on his car?

As gareth says though, probably just the wrong plugs.


Try a set of 071 if they are the same fitment, those bad boys seem to work in everything

 

Cheers Gareth / Chip



EGT's are under 800oC by memory.

Its a GTIR, running std turbo,
1.2 bar boost, with unrated MAF, inj, Apexi boost and fuel controller.

So about 300 -330bhp, so its not mega power, So 12.0 is fine.

 

Sounds perfectly safe to me too then mate.

I'd definately look at the plugs themselves then, either its a diff one or the wrong heat rating.

How do the other 3 look?

Number 2 is the one that sits nearest the turbo on a pulsar isnt it?
(so will be slightly hotter)

 

I haven't seen the car, So i'm going by whats he's telling me,

But i beleive No1 is normally the one that goes down.


I've just spoke to him, and its 11.8 all way thro, but hit 12.2 for a split second then back to 11.8:1.
He's also using rating 8 HKS plugs, which he says are used on alot of the 400 bhp pulsers.

 

what sort of afr is it cruising to 5psi?

could be eating the plugs with normal usage

 

cheers, but can't see that, as no real load, so no real Temp,


14.0-15.0:1 i think he sed. with EGT's of 450 oC
Which i cant see being a problem, as i run 15.0 on my cars,

 

I think the HKS plugs are the made by Denso. If so, Denso's have a habit for dropping the tip off, in Nissan engines.

Use NGK Iridums IMO.

 

Cheers Christan ,

Have you seen happen on one of your customers cars??

 

There is more than AFR to consider here...

IGNITION TIMING

 

Hi simon,

As sed on first post,
It's not detting, and the EGT's are to cool to be too retarded.

 

Danny,
Just because you cant hear it detting, doesnt mean it isnt. !!
Besides, plug damage could be caused by intermittent problems
relating to fuel and/or ignition.

Fooking cars

 

It weren't detting wen i last checked it with my det can's,

But there is the chance a injector went down, or its flow.

 

...yes the denso plugs have a habit of tips dropping off...the main reason is they are not meant to be gapped from how you buy them!

 

Hi Phil

So regapping them, weakens the tip?

 

Certainly does and explains why they break off!

If you look on the spark plug box it even tells you not to re gap!

(I am talking HKS iridiums)

 

I've told him to bring the car round,

and i'm gonna try some ford plugs for fitment.


Cant believe these plugs are that weak, i've regapped plugs (ngk, champions) tens of times, and never failed