Jump to content
SAU Community

Recommended Posts

So I thought I had all my misfiring problems sorted but nope its back again!!!

Now it is missing after I drive it for a long time on the highway. Usually driving to work and back i give it a bit through the gears and i dont notice it missing, but when I just cruise it on the highway for a while and then try and give it a hit it just misses like crazy. After I drop it down a few gears and take it to redline a few times it gets better.

My theory is that it is running rich and fouling up the plugs, there is a fair bit of exhaust build up on the back of the car and I have seen unburnt fuel spitting out the exhaust.

Any ideas what I should be looking at/changing?

Link to comment
https://www.sau.com.au/forums/topic/398364-r33-missing-after-highway-driving/
Share on other sites

plugs done 2000k's, already got yellowjacket coils, running a covered pod, replaced 02 sensor with a falcon one a couple months ago..

someone has told me to change all the hose clamps on the cooler pipes to those beefy bolt down ones incase it is leaking boost.

My battery is a bit sus as well, could low voltage cause a misfire?

Have you tried unplugging a coil at a time too see what cyl is miss firing? i have brand new yellow jackets that lasted 2 weeks before one died lol. Also the beefy bolt down ones is just a wank factor, unless your running 50psi+ I wouldnt bother, you'd split your hoses before the clamp let go..

Edited by 51NNA

it doesn't miss until I jump on it but...

I've got standard NGK plugs with a 0.8 gap

I've only got the stock boost gauge atm and it was sitting about halfway between the 3.5 and 7 mark...

Turned it down so that it sits just on the 3.5 mark.... it has helped a bit, but I can still hear it missing occasionally.

I have found that once it starts to miss if I turn it off and let it cool down a bit the problem goes away for a while until it gets warm again...

its permanently disconnected at moment cause the dump pipe that i got made has no hole for it, and the car idles like a subaru and hesitates just over idle and thru the revs a bit too, just wondering if its only important for crusing?

its permanently disconnected at moment cause the dump pipe that i got made has no hole for it, and the car idles like a subaru and hesitates just over idle and thru the revs a bit too, just wondering if its only important for crusing?

That's probably your cause - when you disconnect the 02 sensor you are most likely adding 25% extra fueling throughout the entire rev range even onto load.

Edited by rob82

ah ok, that explains it then, cause when its cold its especially lumpy, after a long drive its calmed down a bit, but still sounding like very lumpy cam , which i have no complaints with, cheers for the reply been scratching head about this for weeks.

ah ok, that explains it then, cause when its cold its especially lumpy, after a long drive its calmed down a bit, but still sounding like very lumpy cam , which i have no complaints with, cheers for the reply been scratching head about this for weeks.

Haha dude, thanks for taxing my thread! lol

Ive just bought a new turbo from hypergear...SS1PU, so ill try putting that on with new injectors and Z32 AFM and tuning it and see if that solves anything.

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

    • Hey guys, Just want some advice on r34 GTT ac system. Since I’ve owned it, the ac compressor, doesn’t matter the set temperature or ambient temperature, runs for around 10 seconds then disengages the clutch, then re-engages everywhere 30 seconds or so and keeps repeating this.    is this normal?   I had it recharged today as it was slightly low and thought it would fix it but still does it. it cools fine in summer even prior to the recharge, except for the usual warmup when stopped or in traffic (still yet to wire overheat fan to on with ac)   any thoughts would be much appreciated 
    • To plug the hole. The engine plant may not have known whether the car it was going into had a gauge or not. It was a long time ago and the integrations might not have been fully modern. Or they might not have cared because the extra inventory and processes to save a few cents on the sender might have cost more anyway. But please tell me you are not still confusing the idea of a pressure gauge sender, and an oil pressure light switch. The switch will be out there. In a separate hole. Probably with only one wire running to it. Running the light.
    • Blower needs to go low on the exhaust side, displacing the AC and PS, which you have to decide whether you want to keep and how and where to relocate if you do. Electric option for PS is, at least, helpful. Sadly, there is no workable 12V electric AC of any value. Whilst the blower is the last compression step before the throttle, and so it might seem a good idea to have it near the inlet manifold (as mentioned above), you probably want it to go through an intercooler first, so, having it on the opposite side of the car facilitates that air flow path. The turbo discharges into the blower, so proximity of the turbo's compressor outlet to the blower's inlet is nice. But then you might want to intercool that too, before boosting it again....which would probably be a ball ache. Routing pipes out to the front and back could be a bit shit. If there was room for (at least) a small (but preferably larger) water to air core on that side, then that would probably be the best approach. I guess a reasonable alternative would be to locate the blower where the alternator is (more or less, associated with the inlet manifold, per Matt's thought), and somehow incorporate a water to air core into the manifold, sort of like they do for modern blown V8s. The big difference here though is that those V8s have only the one throttle (upstream the blower) and only the one compression step (the blower) and no need for too much in the way of bypass/blowoff valves. Whereas in a twin charged 6, you do need to think about one or two bypass valves associated with the 2 compressors and you would prefer to have the intercooling done before the air has to pass through the throttle. You'd like the throttle to work approx the same no matter what the compression is doing. But if it is located in hot air stream before a cooler, then sometimes the air will be real hot, sometimes it will be quite cool, and the throttle mapping/response will be quite different between those two cases. The throttle, if sized for hot air, would be too large for cold conditions. It's all a ball ache.
    • Package SC on exhaust side. Remote mount turbo. Still a fair bit of room when you get creative on the inlet side of the motor too. Especially if you can get really creative with the welding, and effectively build it into the bottom of the inlet manifold. Would definitely take some design work, and some trial and error, to make sure flow works well still! Might be easier to just start with the Nissan March though... All the work is already done for you...
×
×
  • Create New...