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dBlast 04-16-2005 08:04 PM

JRSC rough idle with FC TB?
I just finished installing my JRSC and now my 2000 ZX3 has a rough sputtering idle. It seems ok with the throttle open, but as soon as I let off on the gas it starts to sputter and then stalls. I have no CEL or vacuum leaks (I think.)

My FC TB was fine before the JRSC was installed. With the throttle closed the FC TB has 3 bypass holes to let air through to maintain idle. This was fine when mated to the stock intake manifold which has a sloted opening to accept the bypass holes. The JRSC just has one hole slightly larger then the 3 small holes on the FC TB. Is this mismatch the cause of my rough idle? Has anyone else had this same problem with this combination?

I used the same gasket on the FC TB as was installed on my stock intake manifold. Could this gasket be leaking and be the cause of my rough idle? Any ideas?

jezwald1016 04-17-2005 08:35 AM

maybe check to see if your iac solenoid is working,then maybe check your egr valve,disconnect hose to egr valve at idle and see if there is vacuum on hose coming off the egr solenoid,if there is then the solenoid is bad,had this problem before and disconnected this hose and it smoothed out and put a new solenoid on and was good then on...also maybe double check all your vacuum hose connections..and the two hose clamps at the blow off valve... retorque sc and intake bolts after heat cycle....hope this may help...jess

joebuddenZX3 04-17-2005 09:47 AM

hey man, how'd you like the jrsc, does it really give you a good kick at WOT. Are you happy or mad about dumping all that money into it. I just reserved an install date on mine in two weeks!

goinloco1 04-17-2005 08:14 PM

pull your air intake off and look at the butterfly in the tb. should be open a little.
adjust the idle screw until it s, disconnect the batt for a little while, reconnect and start the car and drive it a little while (needs to relearn).
should clear up the problem. sounds like your butterfly is closed all the way, starving the motor for air.

dBlast 04-17-2005 09:26 PM

My car seems to have trouble finding idle. It starts somewhere between 1K and 2K then drops to about 1050 then below 1000 it starts sputtering to point where I have to help it along with some gas to keep it alive. The FC TB was closing all the with the car unboosted mated to the stock intake manifold and it had no problem with idle. I'll try fiddling with it some more tomorrow. My friend is bringing over a JR TB to swap out to see if the problem goes away.

titan 04-18-2005 01:11 AM

this is great u have anwserd my question of wether or not the FC TB will fit the JR blower.but now i have another question asumming your usen the 65mm....will the 70mm fit on the JR and can you get the adapter for an auto to work with the 70mm?

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