hi boost = misfire

[OhSoSlow]

Hey guys, got a frustrating problem, and have had a bit of a search, but most peoples solution doesn't seem to be working for me.. (e.g. gapping down the plugs)

I got my car (b18c) tuned a couple of weeks ago, low boost of like 8psi, high boost of 13 psi .. then about a week ago, I noticed a decent flatspot on highboost between about 4500-5500rpm .. then car would take off like normal.. this progressed into a blatant misfire around those rpm, before running sweet up top, and down low. Now it's gotten to the point where if I put my foot down on high boost it just misfires and doesn't accelerate at all! Low boost is fine, had a slight misfire last nite, which seems to have gone away with plug change today.

I'm running an External coil.. It was an MSD, and problem was there, changed to a GT40 coil, problem still there.. Have got newish leads (Genuine honda) have checked them, and they're all fine.. Have changed HT lead a few times, to no avail. Have put in new plugs, Also have gapped plugs down to 0.5mm (They were 0.6mm when tuned)

Problem definetaly seems to be getting worse rather than better, And I'm at a bit of a loss..

Reading up on past threads, has brought up the Ignitor? Is this likely? Worth replacing just in case?

Any other ideas before I set fire to the hunk of junk? Possibly tune? Something completely unrelated to spark?

[Demon]

plugs to hot? have u tryed a colder plug?

[OhSoSlow]

BKR7E's.. pondered that myself.. but they were working sweet.. and have been replaced with new ones..

[Antz]

What computer you running
Had a similar problem with My microtech due to the honda igniters/dwell
There is an old post from Entice about it
Changed to wasted spark and all was fixed

[OhSoSlow]

Oh, just running Crome chipped ECU..

Yeah found the post by Entice, but also seems like most people are able to run standard dizzy with no worries..

Just seems weird, in that it was running sweet.. and has steadily gotten worse, almost as though something is breaking down slowly..

[VTAKYO]

I have heard of problems arising when MSD coils aren't kept upright, meaning oil isn't sitting evenly within the HT coil... and you get arc-over which burns the coil out slowly. A far fetched situation... but possible nonetheless.

[OhSoSlow]

I'm open to any ideas.. the coil is sitting about 10 degrees off upright..

But it has been replaced with a brand new GT40 coil now, and the problem is still there..

[Antz]

Originally Posted by OhSoSlow

Oh, just
Yeah found the post by Entice, but also seems like most people are able to run standard dizzy with no worries..

Just seems weird, in that it was running sweet.. and has steadily gotten worse, almost as though something is breaking down slowly..

Yeah it was mainly with Microtech and I think later in the post he mentioned it could also be a problem with autronic (but don't quote me on that).
But it does highlight the problem with Honda ignitors - and as per your first post maybe this is the problem, can you borrow someone elses dizzy to see if that fixes the problem and then can rule out that it could be a stuffed ignitor?

But hey I am no mechanic and could be pointing you down the proverbal garden path

[OhSoSlow]

Hahaha, yeah I'm tempted to just go buy a new ignitor.. I don't know what else there is in the dizzy that can go wrong?!

Might put the word out on here and see if theres anyone nice enough to lend me a B18c obd2 dizzy for an hour.. *hint hint everyone*

[vtec_junky]

check your plugs again, try pinpoint which cylinder/s are missfiring, by plug condition, im guessing they are gapped according to boosted conditions?
just get another set of plugs and swap them out too, i have had serious issues with misfire a while ago, turned out to be plugs/wiring and faulty sensor in the dizzy, the one closest to the head, but my car would just shut down completely and not fire, that was caused by the sensor

[Cannabis]

found this on MSD web site

The Blaster Coil is designed to mount in most factory canister coil mounts. MSD also offers
a Chrome Coil Bracket, PN 8213. It is recommended to mount the PN 8202 and 8223 coils
in an upright position. The High Vibration Coil, PN 8222, can be mounted in any position
due to its epoxy potting compound.

looks like i better find a place to mount it upright!!!

[OhSoSlow]

Judging by the plugs, they're all having a go at misfiring, not linked to just one cylinder..

Yeah, it's running sweet off boost, and on low boost.. but as soon as you flick over to high boost.. it sh*ts itself in a major way.. which makes me think that the spark isn't strong enough and it's getting blown out.. possibly from a dodgy ignitor?!

[xsiv]

i didnt know about the coils been upright, mins on about a 20degree angle time to change

[turbozxi]

Gap the plugs down real tight and take it for a whirl, who tuned it?

[OhSoSlow]

How tight is real tight? I thought 0.5mm was pretty small?

And Speedfactor tuned it..

[Hayce]

Definetly swap out the igniter, what map sensor are you running for that poundage ( ).

Stock ignition should be more than capable, MSD :thumbsdown:

[OhSoSlow]

I need more pounding..

Just GM 3 bar.. nothing exciting..

Yeah, well I changed to MSD thinking it would be better.. and to be fair, has been sweet the last year or so..

Think I'll go see honda about an ignitor..

[BTLF3D]

.5mm is a pretty small gap... i would try swapping ignition to all standard?

[OhSoSlow]

would change it back to standard, but thats a mission in itself.. have to get new cap, coil, rewire things again..

I don't think thats my problem, I think something is tired, hence why it's only doing it on high boost..

Will get an ignitor from honda tomorrow and chuck that in.

(and pray to the honda gods a little)

[turboteg]

is the rev counter flicking when its missfiring? and have you checked all the earths? like other people have said your ignition setup is capable of far more than you're making, and the plug gap is already pretty small at .5mm, plus it has been running ok before this!

[OhSoSlow]

Rev counter isn't flickering at all, drives mint..

Have checked all earths, even added another one on the weekend.. Have checked all vacuum lines, everything seems to be mint .. thats why it's got me stumped! :evil:

I noticed that honda up the road has ignitors in stock, which leads me to believe that it might be a common thing for them to go?!

[OhSoSlow]

Well, bit of an update.. whatever it is that isn't right, has broken completely.. had to get towed home ops: dirty honda!

[BTLF3D]

Originally Posted by OhSoSlow

Well, bit of an update.. whatever it is that isn't right, has broken completely.. had to get towed home ops: dirty honda!

so what happend when it broke down?

[OhSoSlow]

It lost spark..

Borrowed a mates standard dizzy and it drove sweet, so have just brought another dizzy, will go back to standard ignition!

[BTLF3D]

Originally Posted by OhSoSlow

It lost spark..

Borrowed a mates standard dizzy and it drove sweet, so have just brought another dizzy, will go back to standard ignition!

8)