Tuner Sifu's Pls Help on my PFC.

[jameswwt]

Hi Sifu's,
at first when i do my dyno tuning my car got an impressive 299hp without excessive knocking but to my horror my problem started after i replace a muffler, new bov, new blizt s.s air filter and re-arrange my fuel system (Initially the fuel pump is direct to the ignition and today ive changed it back to normal and added new fuel pump relay) but after that my car knocking is even more worst....
My mech have double confirm on the fuel pump volt supply and it is around 13.3V when idle and 13.8+ when rev...So,its seem normal on the voltage and FPR still maintain at 2.8 bar.

Wat happen??? I didnt touch anything in the engine and why suddently my car knocks so badly?

Wat should i check? Wat should my tuner look into? The setting is still the same...

Any Sifu mind to share abt this PFC problem?

 

[Gh0sT]

what is your knocking level before and after?

 

[jameswwt]

My initial average knocking level after just tune is around 30 - 40 when hard driving but now shot up easily to 98 whenever i boost (only 1 bar) after i change the fuel wire system as mentioned above.

Will it be the fuel pump problem or the fuel line install incorrectly (return & supply) as it have been uninstall and re-install b4 near the fuel tank and fuel pump?

Any Sifu have any idea (no matter right or wrong is always welcome)?

 

[ftzone]

did you monitor your air fuel ratio? knocking is a serious threat man... dun play play.
also, did you change the RON rating of your fuel during tune and now?

 

[jameswwt]

Haiyoh...Sifu FTZone to my rescue...hehe
Well,ive sent my car for fine tuning yday but the tuner still cant figure out what's the problem lol...He then tune my car on the safe side (more fuelling i believe?) and set the FPR up to 4 bars even when idling??? Will there be any bad effect on this pressure?
Now my car still knocks whenever i floor the pedal hard once awhile...
He has checked the compression & vacumn leak on the engine and everything seem fine and healthy (touch wood yaa)...
Will try other Tuner once ive put in my banana manifold + wastegate...

There are also ppl claimed that it might be the stock air flow sensor cant sense the signal correctly bcos sometimes when the air flow increase the sensor just cant seem to read the signal.
They said i can try to put in a Nissan 300ZX Fairlady air flow sensor bcos it can sense more air accurately when high boost (i might interpret wrongly on my explaination so pls do excuse me ya).
Can Sifu FTZone advise on this?

Ive use RON97 all the while.

 

[Gh0sT]

98 is damn high knocking, can destroy your engine in the long run.

try using v-power, my knocking level on the pfc drop 20+ points when i use v-power. hard driving i get max 62-70, but now only 45 max knock level.

also when using high gear at low speed and suddenly full throttle will cause knocking as you put alot of strain on the engine, try using appropriate gears at certain speed, thats how i avoid knocking for my car, i'm using na so maybe it different from turbo as turbo got lots more torque...heheheh

 

[jameswwt]

98 is damn high knocking, can destroy your engine in the long run.

try using v-power, my knocking level on the pfc drop 20+ points when i use v-power. hard driving i get max 62-70, but now only 45 max knock level.

also when using high gear at low speed and suddenly full throttle will cause knocking as you put alot of strain on the engine, try using appropriate gears at certain speed, thats how i avoid knocking for my car, i'm using na so maybe it different from turbo as turbo got lots more torque...heheheh

Thanks Ghost for yr kind and useful sharing.

 

[ftzone]

hmmm... maybe is not knocking afterall... perhaps some metal are hitting each other. going up on a dyno will ensure that if your engine is knocking, you loose torque & power when that happens...
I thought you can use map instead of karmen airflow sensor when you using PFC? why still need to use airflow wan ah? hehehe.. sorry oh.. i know nuts about PFC.

 

[chrissyong]

hmmm... maybe is not knocking afterall... perhaps some metal are hitting each other. going up on a dyno will ensure that if your engine is knocking, you loose torque & power when that happens...
I thought you can use map instead of karmen airflow sensor when you using PFC? why still need to use airflow wan ah? hehehe.. sorry oh.. i know nuts about PFC.

his one is air flow version bro...the fair lady air flow got better flow from original evo 609 air flow,can read more flow from the stock air flow sensor,many sr20det also use this one model ecu power fc,use fairlady air flow can read over 550whp is confirm no problem~

 

[jameswwt]

his one is air flow version bro...the fair lady air flow got better flow from original evo 609 air flow,can read more flow from the stock air flow sensor,many sr20det also use this one model ecu power fc,use fairlady air flow can read over 550whp is confirm no problem~

Thank you Handsome Chriss...

 

[rev555]

i think u saw the high value of knocking is at the hot wether..la..at the nite time will come down low..dont worry la..just take out the handset ..(*__*) mou gan tai....hehe..

 

[jameswwt]

i think u saw the high value of knocking is at the hot wether..la..at the nite time will come down low..dont worry la..just take out the handset ..(*__*) mou gan tai....hehe..

REV555 what you said might be true also laa...Let me check it out for another few days...