Jump to content
SAU Community

Recommended Posts

ok guys, so my car is missfiring and i dont know why...ive upgraded my coil packs to split fires and my spark plugs to iriways which were like $36 a pop and were recommended on the forums and are only like 1k km old ..so whats next? im thinking of just cleaning the coil packs and giving that a go and also i dont have a cover over the coil packs and i heard that lets moisture in? so i might search for one because i have my car booked in for a tune next week :devil: any help would be great. thanks

Link to comment
https://www.sau.com.au/forums/topic/321356-yes-another-missfire-thread/
Share on other sites

running 12psi but it spikes 14psi, i got the ngk iriway spark plugs they come already gaped at .8mm.....im guessing maybe its because i bought the split fires second hand...but ive had them for like 6 months and no problem..im hoping its not the coils, and not the spark plugs lol because ive spent heaps on both of them. its not a really bad miss fire, just a few pops

no i havnt had it washed or detailed, only when i have it on high boost it will pop when hitting 5k rpm, on low boost might pop a tiny bit. i heard wrappin ur coil packs in silcone works, wot kind of silcone do i use?

Well that depends on the purpose of the silicone. Are you trying to retard water and keep moisture out? Are you trying to make a seal? If you're trying to keep water out, get a silicone which is safe for plastics(some of them have harmful fumes which can deteriorate plastics).

Did this start all of a sudden? Did you change anything? Is your engine running rich or lean? If its rich its unburnt fuel, if its lean, it could cause popping and it could mean your fuel pump is failing and falling behind when hitting high boost.

no i havnt had it washed or detailed, only when i have it on high boost it will pop when hitting 5k rpm, on low boost might pop a tiny bit. i heard wrappin ur coil packs in silcone works, wot kind of silcone do i use?

sounds like the stock ecu trying to protect your engine from too much boost, it will probably go away with the powerfc fitted.

ok so i was bored at 1am and decided to pull apart my engine bay, i took out the coil packs and cleaned them with silcone spray coz they were WAAAY too dirty all over....pulled out the spark plugs, and i noticed 1 spark plug had alittle hairline fracture on the side of it, but because i didnt have a spare spark plug i just put it all back together n thought id give it a run...and now its not miss firing, could cleaning of the coil packs make it stop miss firing? and should i replace that 1 spark plug?

If it missies again its because its hitting 14psi with 1.1gap and just use the cheap copper ones if gona be running more than 12 psi get yourself a set of bcrpre7s like $3 each and they come gaped at 0.8 and that will not missfire under high boost. But yeah could of been just maybe the sparkplug was to loose or the coil pack wasnt on the spark plug well if its gone now.

sounds like the stock ecu trying to protect your engine from too much boost, it will probably go away with the powerfc fitted.

This is most likely your problem.

If I remember correctly, stock ECU will have hissy fit when you run more than 10psi boost.

Get PFC tuned, it should solve the problem.

If it missies again its because its hitting 14psi with 1.1gap and just use the cheap copper ones if gona be running more than 12 psi get yourself a set of bcrpre7s like $3 each and they come gaped at 0.8 and that will not missfire under high boost. But yeah could of been just maybe the sparkplug was to loose or the coil pack wasnt on the spark plug well if its gone now.

they arnt cheap spark plugs bro, they r ngk iriway7's $36 ea gaped at 0.8mm, i think it was because they were abit loose or coz the coil packs were dirty coz now its working fine :S.

they arnt cheap spark plugs bro, they r ngk iriway7's $36 ea gaped at 0.8mm, i think it was because they were abit loose or coz the coil packs were dirty coz now its working fine :S.

Nah im saying you should use the copper ones there the best at the end of the day. The iriway and all that is just waste of money for no gains.

Nah im saying you should use the copper ones there the best at the end of the day. The iriway and all that is just waste of money for no gains.

oh ok, well thanks for that..if it starts miss firing again i might go those then

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Input shaft bearing. They all do it. There is always rollover noise in Nissan boxes - particularly the big box. Don't worry about it unless it gets really growly.
    • For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
×
×
  • Create New...