Jump to content
SAU Community

Recommended Posts

ok so mods as follows.

standard 25 neo

bosch 044

725 injectors

Z32 AFM

return flow FIMC

turbo back exhaust

GT3076

Nistune.

265 rwkw, 11.8 AFR, 16 PS

...................................................

so last week added splitfires, and changed my spark plugs from bcpr6es to bcpr7es.

Got a retune a few days later.

went on a cruise last night in the pouring rain, and after some mild driving for a few hours , my car started to violently miss fire across the rev range under boost and so i went home.

Next day i pull the plugs to find all fine, a little rich looking, but number six earth point is melted...

Put the old plugs back in, go for a run, still missfiring.

Check plugs again and there all fine.

Check AFM ( which is in the cooler pipes), to find a large amount of moisture inside the pipes.

After investigating, considering the down poor last night, im fairly confident the water was sucked in my intake.

Im letting the cooler and pipes dry out over night so i havent driven the car.

Im not to worried about the water, but the single melted plug as me scared shitless....

Im stumped as to what it could be...

HELP!!!

post-65812-0-11276400-1324210184_thumb.jpg

post-65812-0-97072500-1324210227_thumb.jpg

Link to comment
https://www.sau.com.au/forums/topic/386055-one-spark-plug-melted-rest-are-fine/
Share on other sites

Injectors for sure.

We flow test every single injector from new. A lot have to be at least cleaned, some returned to the supplier.

These are brand new straight out of the box injectors. Its the most logical place to start looking.

sounds like a plan then.

pretty shit considering i was planing on driving home to Sydney from Adelaide on Wednesday...

there goes that plan lol.

ill pull the injectors and have them cleaned...

What about your store bought injector cleaner?

ive got some liqui moly injector cleaner laying around...

worth a shot or not?

do a comp test on it and get your injectors clean. should aleays try and fill up at a quater if you ever get to see the bottom of a fuel tank you would never drop it low again. you need to get them cleaned properly your motor is worth it

Edited by Bsa

Very odd that it was running fine before the tune, 6 cylinder tends to run alot warmer then the rest of the cylinders so generally the tuner will/should add a little more fuel to it to keep it cool... If this hasn't happened then the cylinder runs lean and can cause detonation/ even pre ignition in extreme cases.. Also a melted spark plug may occur.

Clean the injectors, though I wouldn't be putting my eggs in that basket.. Defiantly compression test, you may have mashed ring lands or even a hole burnt in the top of the piston..

Let's hope not anyway...

Ps don't buy that injector clean stuff, pull them out and get it done properly

Edited by GTR_JOEY

What about your store bought injector cleaner?

ive got some liqui moly injector cleaner laying around...

Ps don't buy that injector clean stuff, pull them out and get it done properly

this, dont use the snake oil, get them properly cleaned if you pull them out.

the only way i can think of the water contributing, is if , by pure chance, water got into that cylinder, hydraulic locked it slightly, bent the electrode to touch, and it melted from there.

would be a 1 in a 1,000,000,000,000,000,000 type of thing.

owuld be checking advice above, and progress from there.

good luck.

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

    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
×
×
  • Create New...