My car has started to get a missfire at 1.8bar and its getting right on my **** I know that there are some high power scoobs on here in excess of 460bhp so any help would be appreciated, checked all the usual boost pipes, coil packs are no more than 2 years old running map sensor so defo not maf aaarrghhhh.


Cheers Dougie

 

you need ether uprated coilpacks or some NGK 7434-8 plugs. We run the coils on our TimeAttack car and have sold a number to people in your position. The plugs might be enough on their own, but maybe not.

 

NGK racing 8s i guess but as Paul said, uprated coils might be needed also.

 

Thanks for the reply Paul, I did a search on 22b and found a thread done by gazza1980sti with the same sort of problem as me and he sorted it with some of your TM coils, I think I will try the plugs then maybe coil packs from yourselfs.

Cheers Dougie

 

Cheers Frayz gonna try the 8s and see how it goes, just want to get the missfire sorted before I fit the nitrous .


Cheers Dougie

 

From what I remember Dougie, I had the same problem with mine...

8 plugs needed, then some coil packs..

I couldn't be ar$ed, so I sold the damn engine...

 

I'm running NGK PFR7B's gapped to 0.6

 

Racing 8's for me

Banny

 

I assume the ignition system on a Newage is better then as I believe I have 7's in as well. Plugs have been in for over 15k miles and I have never had any misfires.

 

Ignition system on a newage is far better than the early classics.

 

Update!!! I changed the plugs for 8s and I thought it cured the missfire but after driving it hard for 25/30 mins it started again, it only seems to happen when getting really hot I rechecked all the pipe work as when just hitting full boost there was a hissing just as the missfire started, could it be a fualty dumpvalve loosing pressure at 2.0bar then altering manifold pressure causing a missfire????? any ideas


Cheers Guys in advance


Dougie

 

Blank off the dump valve and go for another run.

 

Thats the plugs i use...

 

I also used to use Racing 8's
Now use Iridium IK01's on advice from Bob

Used to have mis-fire issue but with some very aggresive runs it went away after a couple of weeks - Bizarre..........

Where can you buy something to blank off the Dump valve (APS) - can you buy them especially? - certainly should be cheap!

 

Just a couple of silicone pipes bungs should do the trick, no need to buy something especially for them

Banny

 

Where can I get them? - would be a reasonable sized bung in the APS pipe between the dump valve and the engine intake

 

I bought the pipe from a local motor factors. I blocked either end off with the small silicone pipe and bung that comes with a vta dump valve kit.

If the intercooler pipe size is larger just buy a slightly larger silicone pipe and appropriate sized bung, also remeber to block the vac inlet off on the inlet manifold.

Banny

 

If you look at this picture you can see how the dump valve part has been blocked off with blue samco hose

 

So you've got a bung in the middle held by the 2 jubilee clips
I did this but the bung I was using blew out under pressure - need a better bung - just didnt know where to get from....
Nice engine

I have to deal with crap clutches, blowing gaskets and stupid engine support bracket at the moment, once done my car will be better.... live and learn with some garages

 

I had something very similar to this last year. I tried re earthing everything, changed leads, coilpacks, plugs etc. In the end it was a bit of grease on the face of the crank sensor. It would only cause issues every now and again but always reared its head when the car got hot and had a few hard runs.

Try cleaning crank and cam sensors. It's a bit of a long shot but it worked for me.

Cheers

Daz

 

Cheers Daz I will have a look at that over the weekend and I will try all other ideas and post outcome.


Cheers for the replys

Dougie

 

Hi Steve, are you not running a dump valve on yours?


Cheers Dougie

 

Never ran a dump valve on mine. Thats the way the big power builds work

 

Mmmmm didnt know that, what is the reasoning behind it?

Cheers Dougie

 

pay's for the wastegate!

 

lol @ Paul. How many £400 dump valves do you sell then

 

Tial maybe

 

My last wastegate from paul was only £270

 

But yours aint big power!!!

 

pmsl at shaun The cars away now for my heads to be refitted and my new rods, After that is done my car is ready to be mapped properly. The proof will be in the 1/4 mile and I'm hoping to get mine into the 10's