car dont idle - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

idiot goes sideways · 11-25-2006, 01:58 PM

built up my ca18det and it doesn`t idle at all !!!

i can hold it only with the gas pedal and its strange like it response to the pedal

if i get of the gas it stalls, if i step on it lightly the engine rev up to 2000rpms (even with little throtle) and stalls again, if i pump with the throtle i can keep it from stalling but it rev up to 2000rpm`s again and stall again.

i cant keep the engine with the throtle at rpm`s, like 1500 ore 2000rpm`s it revs up alone and stall afterwards

the mods are

s15 turbo
power fc
534ccm injectors + fuel pump
z32 afm
270° tomei 8.80 lift cams
lighten crankshaft/ flywheel ( all togheter about 4,5 kilo less weight with pistons and rods)
forged piston/rods (compression ratio 8,2 :1)
mhg with studs
s15 turbo

with these mods it doesn`t idle and was backfiring heavy

to test i was going back to stock cams to figure out what the problem is,
the backfiring is gone now but it doesnt idle, like i wrote above

the a/f is right about 12,5 :1 under load
i cant realy check my ignition timing when car doesnt idle
also the self learning idle program from the power fc doesn`t work when the car is not idling

i checked the throttle body and the valve for idle

so the cams are not the issue...
could it be that ligthten the crank flywheel is the problem......

i`m starting to geting clueless, ive got not much experience with modified engines (my first moded engine) so anyone a clue??

zugoi · 11-25-2006, 03:24 PM

sounds like some sort of vacuum leak. Are you running a stock intercooler or aftermarket one? Check all the connections and make sure they arnt leaking air in.

idiot goes sideways · 11-25-2006, 04:26 PM

the lines are fine, and i run a aftermarket intercooler but drove this one with my stock engine ago so it should be okay

anyway if there would be air leaking in, the car would rev up alone and that doesn`t happend if i go of the throttle it stall`s................maybe i`m wrong

but i check for leaks, just in case,
any other ideas??

ViZion Zs · 11-25-2006, 05:55 PM

wiring issue.. or a bad coilpack.

*NemeGuero* · 11-25-2006, 07:10 PM

Sounds like your tune is crap for what you've built.

The vacuum lines may appear OK but do a pressure test on your IC piping.

11-25-2006, 01:58 PM	#1
idiot goes sideways Leaky Injector Join Date: Jul 2005 Location: austria Posts: 105 Trader Rating: (0) Feedback Score: 0 reviews	car dont idle built up my ca18det and it doesn`t idle at all !!! i can hold it only with the gas pedal and its strange like it response to the pedal if i get of the gas it stalls, if i step on it lightly the engine rev up to 2000rpms (even with little throtle) and stalls again, if i pump with the throtle i can keep it from stalling but it rev up to 2000rpm`s again and stall again. i cant keep the engine with the throtle at rpm`s, like 1500 ore 2000rpm`s it revs up alone and stall afterwards the mods are s15 turbo power fc 534ccm injectors + fuel pump z32 afm 270° tomei 8.80 lift cams lighten crankshaft/ flywheel ( all togheter about 4,5 kilo less weight with pistons and rods) forged piston/rods (compression ratio 8,2 :1) mhg with studs s15 turbo with these mods it doesn`t idle and was backfiring heavy to test i was going back to stock cams to figure out what the problem is, the backfiring is gone now but it doesnt idle, like i wrote above the a/f is right about 12,5 :1 under load i cant realy check my ignition timing when car doesnt idle also the self learning idle program from the power fc doesn`t work when the car is not idling i checked the throttle body and the valve for idle so the cams are not the issue... could it be that ligthten the crank flywheel is the problem...... i`m starting to geting clueless, ive got not much experience with modified engines (my first moded engine) so anyone a clue??

11-25-2006, 03:24 PM	#2
zugoi Zilvia Junkie Join Date: Aug 2003 Location: Bay area Posts: 560 Trader Rating: (0) Feedback Score: 0 reviews	sounds like some sort of vacuum leak. Are you running a stock intercooler or aftermarket one? Check all the connections and make sure they arnt leaking air in. __________________ Drunk posting FTW!

11-25-2006, 07:10 PM	#5
NemeGuero No more nissan. Join Date: Jan 2003 Location: RAIN, Washington. Age: 40 Posts: 8,132 Trader Rating: (10) Rides Gallery: NemeGuero Feedback Score: 10 reviews	Sounds like your tune is crap for what you've built. The vacuum lines may appear OK but do a pressure test on your IC piping. __________________

11-25-2006, 04:26 PM	#3
idiot goes sideways Leaky Injector Join Date: Jul 2005 Location: austria Posts: 105 Trader Rating: (0) Feedback Score: 0 reviews	the lines are fine, and i run a aftermarket intercooler but drove this one with my stock engine ago so it should be okay anyway if there would be air leaking in, the car would rev up alone and that doesn`t happend if i go of the throttle it stall`s................maybe i`m wrong but i check for leaks, just in case, any other ideas??

11-25-2006, 05:55 PM	#4
ViZion Zs Zilvia Junkie Join Date: Oct 2006 Location: Orange co Age: 46 Posts: 328 Trader Rating: (0) Feedback Score: 0 reviews	wiring issue.. or a bad coilpack.