bad/rough idle after installing cams

[naha_music]

i raised the idle today to around 1100rpms, it improved the vibration some, but still running alittle rough. this weekend i'm going to check the timing and possibily run down to a local nissan tuning shop (KN Factory) to see what they have to say..

 

[DeanS15]

its not severe matt - very tolerable. but when warmed up it doesnt hold a 100% steady idle. i suppose with an adjustable pulley on the exhaust side i may be able to tidy it up a bit but tbh im not even worried about it.

 

[naha_music]

i thought i had fixed the idle to around 1100rpm yesterday, but today i had cranked it up and let it warm for alittle bit.. after a few minutes, it dropped from 1100rpms back to around 800rpms. also, i noticed when i give it alittle rev and let go, when the rpm drops back down, it sticks at around 1500 for a couple seconds before it drops back down.. it does this constantly. any ideas?

 

[DeanS15]

could that be the idle control valve adjusting back down to 800rpm despite you setting it to 1100 on the screw? it would make sense.

 

[Matt_S]

You need to set the revs without the IAC plugged in IIRC.

 

[naha_music]

just an update:

i got the idle adjusted, but it still ran alittle rough. i didn't have a timing light readly available, so i adjusted the timing by sound... i did manage to smooth out the idle even more. this will have to do until my timing gun (that i order over 2 months ago!) comes in.

 

[TriniGT]

There is a sequence to adjust the idle on the SRs you know that right, not just a matter of adjusting the idle screw but actually allowing the car toreach operating temperature and then revving it to 4000rpm a couple of times and then unplugging the TPS solenoid and adjusting the idle via the idle screw and then plugging back in the tps and then revving it again and then leave it for a minute or so and then switching off the engine and then restarting. adjusting the idle using the screw will adjust it for that one time and when you switch off and restart it will go back to how it was as the ECU will adjust it. Revving the car to the 4000rpm and unplugging the tps signals to the brain that it is in the mode needed to adjust the idle then revving after indicates that you're done adjusting.