R33 Running A Bit Rough

[Murry33]

My r33 gtst has been running a bit rough lately, seems to run really rich and i can smell fuel......it's just been sluggish really. problems so far are:

- Fuel pump is loud, and car has trouble starting in the mornings (i'm assuming i'll have to change that this wk, how much are they usually?)

- I don't seem to be getting much boost, even if it's a cold night and i give it a fair bit! (was boosting great a week ago though..)

- & i'm thinking the bov is leaking perhaps as when i adjust it, it tends to stall at random times!. (could be the fuel pump)

OK It's just have a full service, people have been recommending a dyno tune?. Since i have the stock ecu will the dyno tune fix the car from running rich and overall improve it? What have your experiences been with dynos using stock ecu?, any decent power increases?

oh and before somel start saying "do a search" i have, oh yes really it's true lol. but i couldn't find the exact answer i was looking for, so i'm asking you's k thnx cheers!

[mickr33]

You have PM.........

[chinkeboi]

if its a stock intake fuel pump then it should be relatively quiet. It getting louder usually means its on its way out. That or you have a aftermarket pump.

Hard to start in the morning could be your injectors are clogged/dirty/broken. That or sparkplugs.. most likely the injectors though.

lack of boost could again be fuel pump.. or afm or many other things.. my moneys on ur fuel pump.

don't just tell your mechanic to change the pump.. ask him to test the fuel pressure first.. as it may not be it

[mad082]

dyno tune won't change a thing as the stock can't be altered without a remap.

the problem could be that you either have a bad boost leak (check intercooler piping), the afm is stuffed, or the turbo is stuffed.

[Murry33]

Thanks for the replies! i'll check the fuel pump, the car has fmic,bov,cat back exhaust system.

Might change the bov to a stock one? would that be okay running say 10psi boost?

[mad082]

i have a stock bov running 14psi.

[Murry33]

cheers mate!, i've got a plump back GFB bov, that can be adjusted to be silent........would that make it legal you think?

[mad082]

should be legal if it is plumback.

[Murry33]

turns out the lack of boost was a huge air leak in one of the rubber hoses..&

ok well i talked to the mechanic, he'll check out the fuel pump tommorow. I was going to get steel piping done to replace some of the rubber/plastic piping from the turbo to air filter already there but he thought it wouldn't make much difference performance wise.

So i will probably be getting a dump pipe installed instead and boost switch to change between stock boost & 12psi boost ?. let me know what you think!

Edited December 11, 2006 by NeesaanGTS

[ky_r33]

turns out the lack of boost was a huge air leak in one of the rubber hoses..&

ok well i talked to the mechanic, he'll check out the fuel pump tommorow. I was going to get steel piping done to replace some of the rubber/plastic piping from the turbo to air filter already there but he thought it wouldn't make much difference performance wise.

So i will probably be getting a dump pipe installed instead and boost switch to change between stock boost & 12psi boost ?. let me know what you think!

If your car is running rich, it could be the oxy sensor. Mine was chewing thro the fuel, then i had it dynoed and had the oxy sensor replaced and it run heaps better. My car is stock and has 160kw @ the wheels

[Murry33]

thanks! i'll ask the mechanic to check that too, mine is chewing a fair bit of petrol actually..........ahh skylines when does it end ? lol

Does anyone know what sort of power gains you get from getting a new turbo dump pipe??

[Murry33]

Okay well i got quoted: $220 for oxy sensor(broken), $750-dump pipe,gaskets, 3inch cat converter. Then a few hundred extra for dyno tune before/after. do these prices seem right?

[RBwhatever]

Okay well i got quoted: $220 for oxy sensor(broken), $750-dump pipe,gaskets, 3inch cat converter. Then a few hundred extra for dyno tune before/after. do these prices seem right?

O2 Sensor - $80 from eBay, you can probably get it even cheaper elsewhere.

Ebay O2 Sensor for R33

3 inch Xforce Hi Flow Cat - $199 from Just Jap.

3 inch Xforce Bell Mouth Dump/Front Pipe (1 Piece) from Just Jap

Stainless - $330

Mild Steel - $195

http://justjap.com/parts_nexhaust.htm

or if you want a split dump, check out the group buy for batmbl split dumps and front pipes and hi flow cats.

http://www.skylinesaustralia.com/forums/in...howtopic=136607

BATMBL Stainless Split dump and Front pipe and 3 inch Catco cat - $540

Edited December 12, 2006 by KeyMakeR33

[Murry33]

Thanks! yeah those prices are with labour included etc that i quoted, so i suppose it aint a bad price.

Will the dump pipe give me much performance increase over what it is now(stock)?

[RBwhatever]

Huge difference. Just bump the boost up to 10 or so and it'll be a different car.

If you and a mate are handy with a spanner, then you can do all that bolt on stuff yourself. Save yourself hundreds of dollars in labour costs.

Edited December 12, 2006 by KeyMakeR33

[Murry33]

Cheers! I hope it's a huge difference. Altogether it's costing me about $1400, with new o2 sensor, 3inch cat, dump pipe, gaskets etc. Also includes before/after dyno tune+labour. I just got the car and it's costing me heaps haha....

Whats the best way to increase the boost, they wanted to install at switch to change from stock/12psi boost.....for like $500 though lol?

i thought there must be a cheaper option..boost controller? but thought they are illegal..duno

[RBwhatever]

Cheers! I hope it's a huge difference. Altogether it's costing me about $1400, with new o2 sensor, 3inch cat, dump pipe, gaskets etc. Also includes before/after dyno tune+labour. I just got the car and it's costing me heaps haha....

Whats the best way to increase the boost, they wanted to install at switch to change from stock/12psi boost.....for like $500 though lol?

i thought there must be a cheaper option..boost controller? but thought they are illegal..duno

Turbotech BC

Got a spare 30 bucks? one of these is more than adequate. Takes 5mins to fit.

[Murry33]

Aweasome!, and they wanted $500 lol...ttshh. I'll let ya's know how it goes

[Murry33]

OK talked to the mechanic, i thought because it's running rich the new o2 sensor should make it run normal again?. He thinks that even if i replace the o2(which is completely stuffed) it will still run rich as long as it has the standard ecu?

Also hasn't rectified the starting cold in the morning problem, the fuel pump tested out fine...duno?

Edited December 13, 2006 by NeesaanGTS

[Sambo33gtst]

Bro, be very very careful with your boost levels once you have your dump pipe put on. If you fook around with your boost after ur dump pipe is put on, your gonna put ur turbo at risk. A good mod to do when u do a dump pipe is an electronic boost controller. Your not your gonna get boost spikes if this is done, and your turbo will love you forever.

But yes, you will notice a decent difference. Turbo will spool up much quicker.

Edited December 13, 2006 by Sambo33gtst