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R33 gtst missfiring problem?

Hi everyone,

This is my first post and I'm after some help. After reading many threads about people's misfires in their r33 s1 gtst I can't come to a resolution of my problem.

I have a fmic, full exhaust, 10psi.

Under full throttle any gear it makes a mini gun rapid fire out the exhaust with no power. Does not happen when gradually accelerating. I have replaced since it first started; fuel pump, fuel filter, spark plugs gapped to 0.9 (previous plugs were 0.8 and same issue), tried original and super spark coil pack both second hand. Still am having problems

Could it be my igniter? The problem was not there before I installed fmic and bumped up boost. I haven't yet tried sealing my coilpacks with high temp sealant.

I have my car booked in for highflow and tune monday so would like to get it fixed before then

Any advice would be awesome

Cheers Mitch 

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Sound's like R&R (rich and retard).

The stock ecu is seeing more air than it's used to so it tries to protect the engine by adding more fuel and retarding the timing. This would make sense since the problem started after you installed the fmic and raised the boost which would result in increased airflow.

 

This causes a loss of power and the misfiring feeling. You could try clean your AFM with some MAF cleaner and dropping the boost 1 or 2 psi, the problem should go away then.

 

Are you sure you are running only 10psi and not higher?

 

 

 

11 minutes ago, vxsr33 said:

Sound's like R&R (rich and retard).

The stock ecu is seeing more air than it's used to so it tries to protect the engine by adding more fuel and retarding the timing. This would make sense since the problem started after you installed the fmic and raised the boost which would result in increased airflow.

 

This causes a loss of power and the misfiring feeling. You could try clean your AFM with some MAF cleaner and dropping the boost 1 or 2 psi, the problem should go away then.

 

Are you sure you are running only 10psi and not higher?

 

 

Hey,

thanks for your reply. I've got a 32ecu z32afm and a highflow + tune going in Monday. But I just want to make sure everything is working before I give it to mechanic and get charged an extra $100 an hour to repair my coilpack etc.. I'm positive only 10psi boost. I'll try cleaning my afm and I'll drop the boost back to 7 and see how that works

Problem(s) could be from either the Superspark coils (which are rubbish, sorry to be blunt) or faulty OEM ones.

Best to get Splitfire ones or go Yaris conversion or LS conversion coils.

44 minutes ago, Dose Pipe Sutututu said:

Problem(s) could be from either the Superspark coils (which are rubbish, sorry to be blunt) or faulty OEM ones.

Best to get Splitfire ones or go Yaris conversion or LS conversion coils.

Don't really want to spend $500 if I don't have too. Might try afm cleaner and see what tuner does. Do you recommend using that silicon or electrical tape around coils as a resolution? 

1 hour ago, Mitch r33 said:

Don't really want to spend $500 if I don't have too.

Sure, none of us want to spend extra money but if your coil packs are buggered or you spent $400 when you should have spent $600 then the only way out is to spend $600.  Not $500 or $400.  

Always buy Splitfires at minimum.  Do not try and go cheaper.  You will only end up opening your wallet again to buy what you should have bought the first time.

Doubt it's coilpacks as it wasnt like it before I bumped up boost, installed fmic and full exhaust

I wouldn't not doubt the coilpacks in that assumption. I'm not saying that it is your coils either but if they're weak it shows up when boost and power increases.

 

As above, if buying new coils stay away from the bright coloured ones unless they're the bluey purple ones, otherwise OEM or conversion.

 

I'm going to entertain the R and R theory.

 

 

Tried both coilpacks, and screwing boost tee fully which isn't making boost any lower then 9. Unsure why. Might have to plumb it back through my apexi boost controller which used to run stock boost 5-7psi. Will give that a shot tomorrow, if no luck, will try and tape coilpacks or look for cracks in OEM ones. Will R&R still occur when I lower the boost? I know it's running rich because I get 200-250km  tank and that's not even thrashing it

Just now, vxsr33 said:

So did you test drive it at 9psi and it's still cutting out?
Just take off the boost T and use a straight through connector if you have one. R&R shouldn't occur once the boost is lowered.

Yeah I'm going to put it through my apexi boost controller tomorrow arvo, which is turned off so it runs stock boost which it used to. This will tell me if r&r or coilpack 

That should give you approx 5 psi (assuming you have stock turbo with stock actuator and the stock boost solenoid is eliminated) which will certainly eliminate any over boosting and R&R.

R33 stock ecu is notorious for freaking out around the 10 psi mark, sometimes you're lucky, sometimes not.

Definitely clean your AFM / MAF with the proper MAF Cleaner like CRC as even the slightest bit of crud can cause it to read incorrectly.

  • Like 1
9 minutes ago, Got a Pulsar said:

That should give you approx 5 psi (assuming you have stock turbo with stock actuator and the stock boost solenoid is eliminated) which will certainly eliminate any over boosting and R&R.

R33 stock ecu is notorious for freaking out around the 10 psi mark, sometimes you're lucky, sometimes not.

Definitely clean your AFM / MAF with the proper MAF Cleaner like CRC as even the slightest bit of crud can cause it to read incorrectly.

Okay cheers man, I'll grab some CRC MAF cleaner tomorrow.

It's a little exxy but great stuff, I've used it on every car I've owned running a MAF and it has improved idle smoothness and fuel economy on all of them.

Should be part of your general servicing and maintenance routine but is often forgotten.

My R33 (running 10psi) did what yours is doing once but the MAF cleaner fixed it. :thumbsup:

 

Just now, Got a Pulsar said:

It's a little exxy but great stuff, I've used it on every car I've owned running a MAF and it has improved idle smoothness and fuel economy on all of them.

Should be part of your servicing and maintenance routine but is often forgotten. :)

 

Okay thanks for that, if it nots the AFM or the fact it's running higher boost with a fmic, would you definitely say it's coilpacks? Since I've replaced pump and fuel filter already. Would you wrap coilpacks in electrical tape? And if so what part do you wrap? If your not sure all good man

No I would not as there's still too many variables. Start with the easy and cheap fixes and eliminate them first.

What pump did you put in? Did you feed it a new 12 Volt line via a relay or just use existing wiring?

Some after market pumps don't like old stock wiring.

Check the coils for cracking and wrap the whole long bit to eliminate any arcing if need be.

Just now, Got a Pulsar said:

No I would not as there's still too many variables. Start with the easy and cheap fixes and eliminate them first.

What pump did you put in? Did you feed it a new 12 Volt line via a relay or just use existing wiring?

Some after market pumps don't like old stock wiring.

Existing wiring , walbro 255

Might be ok, but try the other things first (CRC and coil wrapping) and go from there.

Heaps of info in this site about all these things as they have all been covered many many times over, so have a mad search, read up on R&R, misfires, Fuel pump installs etc etc.

and go nuts!

I know I sure did. :yes:

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