Need Help With R33 Rb25det

[WET-25T]

Hey,

Ok on the weekend i put a xforce cat and xforce ss 3 inch cat back exhaust. When im boosting and hit 4500 rpm the car kinda stops boosting for a second or 2 and makes a couple of poping sounds from the exhaust than starts boosting again but even harder. It has gotten a little worse since yesterday and is now getting me worried.

Today i changed my spark plugs back to the recommended ones but it made it a little worse so i put my iridium ones back in.

I also sprayed carby cleaner on my air flow meter to clean it but still no effect.

The mods are:

R34 Gtt side mount intercooler

Single boost controller set to 10 psi (just changed it to 9 psi but didnt fix the problem either)

K&N pod filter

And the cat and cat back exhaust

I really dont know what else to do so i need your help. If you need anymore info that i have left out please ask me. Thanks guys

[BHDave]

search "rich and retard" and "misfire" and maybe "coil packs" if you're bored.

One of them will give you the answer you need.

But basically, gap your plugs to .8, if it still does it then get it on a dyno and see what the a/f ratio is like. If it's rich as hell you need an safc or some form of programmable management, if the mixtures are ok then your coils are shot.

at 9psi i'd be inclined to think it's coils or plugs

[tridentt150v]

Or a restriction like old gasket in the exhaust?

Try putting your old exhaust inc. cat back on and see if it fixes it?

[WET-25T]

Whats a safc, i hope not a computer cause i cant afford it atm. Well the plugs are new but i dont think they are .8 gap.

Yea i was thinking about putting the old axhaust back on to see if that fixed it.

Would i need a different afm? Which is better out of a z32 and 145 afm (kinda off topic) for if i do need one?

Cheers

[paulr33]

safc is a piggyback fuel computer a- about $350 tuned and installed

you dont need to change the AFM and you cant without changing the AFM

safc should do the trick

[WET-25T]

Thanks for the help guys but i really cant afford anything like that at the moment, got other commitments and i am only a second year apprentice, almost 3rd. Plus i hav had the car for about 3 months.

I just want the cheapest way to fix it till i can afford a pfc ( which might not be for ages). Would plugs gapped to 0.8 help like copper ones? That would be a cheap fix .

[Mr. Untouchable]

sounds like the same issue I had.

after exhaust went on it was a bitch.

a set of splitifre coil packs did the trick.

access autoworks have them for approx $500

worth every darn cent if you ask me!

[axe s]

Go to supercheap and buy a spark plug gapping tool and gap your plugs to 0.8mm then give it a go... if this doesn't work try 0.7mm but i wouldn't go any smaller... mine took 0.7mm when i put my front mount intercooler on.

[WOG BOY]

is it common for liners to do this after a cat and zaust upgrade?

im thinkin of doin this to mine with a hks model.....tis scaring me now!

[BLK33T]

I had the exact same trouble ...

got new plugs gapped them down to 0.8mm and wallah no more misfire

[Dale FZ1]

Take the boost controller out of the equation and run it that way.

Less boost = less mass air flow = ECU operating away from the rich/retard failsafe.

Taking your plug gaps down might have some effect, as coils could be getting a bit tired. At this stage you'd be lucky to be hitting 180rwkW, so it's not like you've got massive amounts of intake charge to be ignited that are blowing the spark out.

Start saving towards replacement coils and some sort of ECU that will get you around the factory failsafe.

Plenty of reading is available via the search function as pointed out already.

[R31Nismoid]

If you cant afford to correctly tune the car and deal with problems

Then dont modify it.

Otherwise live with the issue that arise from running a non-factory spec car.

Things like coils, plugs etc are all speculation points and things that you must check/test yourself as no-one can tell you over the internet.

[WET-25T]

Sorry i didnt mean to upset you, i will end up getting a computer and other things but cant afford it right now.

Anyways i gapped my plugs to 0.8 yesterday and now the car is fine. Thanks for the help guys i really appreciate it.