I had a problem appear late last year with my car (was fine for about 5 months), as it started to misfire at high boost - circa 27psi+. I fixed it by buying a new set of NGK 9's. The car has been standing for several months and when I took it out a couple of months back for a quick blast it started doing it again very slightly, but occasionaly harder when hitting that kind of boost.

Now the plugs have only done about 300miles so I can't see it being the plugs, but I did take the later set of NGK 9's out and used an older set for getting the car in and out of the garage, until the better whether came for proper driving. I now have the newer plugs back in, but I never cleaned them when storing or when I put them back in the car.

I was told some time ago that these types of power conversions can suffer from misfires at high boost and such things like Jacob's Ignition systems can help.

NGK 9 Plugs are at standard gap
I have motorsport leads on the car (new last year)
The dizzy cap and rotor arm was replaced last year
Coil is the original one
If I turn the boost down to around 26psi it is fine - but who wants to run at 26psi when I have a spanking new T4 to trash the nads off!!!!

Should I have cleaned the plugs up after storing them? If so what should I use to clean up NGK 9's cause the tips are delicate.

Any advice?

 

Shaun

What gaps you running and what type/coluor lead.

Mark

 

Leads!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Get genuine Ford Beru leads on it and i bet it will be fine

 

Mark (as in MAD)

Christ knows on the gap - as they come out of the NGK 9 boxs. Blue motorsport leads, but these were on it for the five months that it was fine before it started misfiring the first time - these were brand new when the engine was done in Jan 03.

 

Shaun

My own 500 would run 22thou gaps,at 37psi used a lot ,Standard leads, change plugs about every 3k no problems at all.

Mark

 

I have had issues with my "909" leads, changed em back to standard and fixed the problem, got the blue ones on at the mo tho, but problem is back.....

Swapped to make sure it was the problem....

 

See, Standard leads

Told you

If you want to try mine on your car Shaun, you can pop over and borrow them mate

 

Mark (MAD)

So is that change my leads then?

Tiff,
Will pop over some time and give them a bash if thats ok.

 

Whats the price of the original leads..... couple of hundred?

 

Thats fine mate,anytime

 

Shaun

First thing I would do is check and regap plugs,Standard leads will be best if you buy some make sure they are Ford leads I have seen some people trying to pass off others as stock.

Mark

 

Cheers for the info folks.

Will check and re-gap plugs and then if that don't work I will test with Tiff's leads!

Can and should I clean the plugs up.... if yes I assume I can't use a wire brush?

 

I think the Ford Beru leads are about £40-50 each

 

Use a multimeter and check the resistance of each lead, mine were all under 7k ohms when i last checked them. The problem is the connectors used on the 909 leads (the ends that go on the dizzy), they fur up over time, to the point where the mutimeter can't get a reading!

I had an old set of Ford(beru) leads, one of which was broken, so i took all the connectors off both sets of leads and put the ford connectors on the 909 leads, job done!

 

My misfire was the valve springs in the end. Bloody misfires, they have to be one of the most annoying problems you can get on a cossie.

Sean..

 

Shaun,
The 9s as std are gapped at around 0.7mm (28ishthou) and are far too wide for your conversion.

I personally doubt you have any problem other than this, and they need gapping down to around 0.6mm for your 30+psi T4 setup.

Leads may well be fine depending on age/wear/type Id advise a change to the late 92+ style cap and leads personally if anyone is buying leads.....

 

Cheers Stu. I'm sure I just took them out of the box and banged them in, but then I may of re-gapped them....... just can't remember. I will check though.

 

thought it was at stigs place shaun?

 

Shaun,
Please admit that you have invented this misfire story to convince us you have explored the upper limits of your car's power . However, as I know you're a woman, your rouse has been exposed .

 

AFPMSL@ Mike

 

 

Matt,
It was, hence the nice new T4 on it but I picked it up yesterday. TBH I forgot to mention the misfire problem to Tony (as it had been that long since I had driven the car on full boost because I knew the turbo was tired and turned the boost down to 22psi) and after speaking with Mike @ TS, I discovered that due to the rain over the past week the car had only been test driven on low boost hence why Tony never knew about the misfire.

Mike,
Your only jealous as you can't get anyone to explore the upper limits of your anus capacity!!!

If driving at the upper limits of my car means I smash over round-abouts and hit armco then......... than I am more than happy pootling around at 26psi!!!

 

 

 

Given your driving skill is worse than mine, that is quite likely, so stick below 26psi

 

Life is full of making acceptances....... your make yours and I'll take mine gay boy!!!!



You can always work out the thick people...... as when they throw a pepple they never check that the adversary has HUUUUUUUGE fooooooooking granite blocks to throw back!!!

 

.

 

Fook me, that's saying something

 

ahhh right i see shaun

when mikes car gets the boost turned up he has to fit larger bull bars

 

Fagin,

have you sorted it yet?

IMO on that spec the plugs need gapping down to 24 thou.........otherwise it will missfire on boost!

 

Doug,
Don't be silly!!! It's been raining and going on my past record I would have to wait a further 4 months before even looking at the car again!

I will have a look at it on Sunday if I get some time.

Fingers crossed!!!

 

Plugs seemed to have been gapped to 24thou (as I had an incling, but they were'nt mega tight at that on the feeler gauge)..... now re-gapped to 23 thou (.584mm)....... I will try the car tomorrow (if it's dry), but I have a feeling I will be borrowing your plug leads Tiff!

 

Shauna, get a volt meter and check the voltages at the coil and compare them to the voltages at the battery with the car running if you haven't already done it....

The coil voltage should be as close as possible to the battery voltage.