Hi, I just installed my skunk2 manifold on my gsr motor and I'm plauged by a wierd idle problem, the car [when the iacv] is plugged in, idles @ 3k rpm untill the car warms up then it idles @ 1.5k going +/- 200 rpms, I unplug the iacv and it does the 1.5k idle thing, it is drivable, everything seems to function but I wanna know what is causing that. I used new gaskets, scraped the old ones off. I replaced the gasket on the iacv and problem still is there. I thought there would be some leakage between the manifold/tb and there's none [sprayed carb cleaner @ it]. I did a search and only thing I would guess is a fast idle thermo valve [under throttle body] or the iacv behind the manifold. I also checked coolant levels and vacume lines. I did the tb pulley swap from my old 1.5l throttlebody, would that also have any effect?

Cliff Notes. '95 b18c1, skunk2 manifold, evap system bypassed [vacume caps where they are supposed to be], evap disconnected, 2ndary butterfly plug disconnected. New gaskets, gsr throttlebody and 1.5l dx pulley, car idles @ 3k when iacv plugged in, idles @ 1.5k when disconnected/car is warm. Car is drivable, but idles like a bastard. I would appreciate it if someone helped me out here, thanks a bunch.

 

Too much air is getting in somewhere. Throttle cable too tight, throttle stop screw too tight, bad pcv valve, stuck fast idle valve, bad eacv, intake manifold gasket leak,throttle body gasket leak, brake booster leak. Sounds like you have eliminated a couple of these potential problems, but there are several that need to be checked. Also check your ignition timing , too advanced will idle too high. your ECT can also cause a high idle-if the ECT is sending a too cold signal, the ECU will raise the idle. But unplugging the EACV(IACV) eliminates that possibility.

 

coo, thanks. I am going to check the Fast Idle Thermo Valve, and my IACV.
I was thinking vacume leak, but if I disconnect the IACV and it idles variably @ 1.5k rpms, could the intake manifold gasket / tb gasket be a possibility. EDIT: idle only surges when I have the iacv plugged in, it was worse before, it idled @ 6k untill I rerouted some coolant hoses [looking @ my friend's b18c1]

PS. I have a '95 b18c1, and my friend had a '99 b18c1 [obd1 vs obd2], I seem to have more coolant nipples than he does, like the one behind the thermostat housing on the block, and then there's a seperate one on the intake manifold itself that tees off the main one on the intake manifold.
Could coolant lines also play a potential problem? Thanks.


[Modified by Death Scythe, 7:50 PM 1/5/2003]

 

did you get a CEL after, you swapped to the skunk2 intake manifold! i did changed one on my friends 96 gsr, and after we were done we got a CEL. I'll check to see what code it's giving when i get a chance!

 

I did get the cel, but that was because a friend disconnected the map sensor [while running] and stalling the car out, and I also disconnected the IACV to get to work. I got a #3 and #23 I believe, the 23 is the knock sensor [off top of my head?]?? How would that effect the idle @ all.

PS. Could a bad Intake Air Temp sensor cause bad idle? Or what about a bad MAP Sensor?