Changed isc and now is my idle is worse!!

[Dopeem1]

Ok guys i changed my isc with a brand new one and now my car is acting super strange.

Before replacement it would surge from 1k-1500 really slowly. Now with the new idle speed motor, it starts and immediatly revs to about 3k rpms for about 5 seconds and the drops to 1500 and sureges to 2000 rpms extremly quickly. Now what would the issue be? Should i unbolt the isc and see if the valves moves? Should i go back to autozone and throw it at someone? Im starting to get a lil perturbed by this stupid idle problem... I went based off the guide on vfaq and only thing i have not done in rip into fiav yet...

Thanks again guys!!

 

[Brunoboy]

Rofl, the cars not for the weak. It's letting you know that you're in for a long expensive ride. Anyways, it's probably your intake setup, your non recirculating blow off valve and you shitty safc. Aha really though, and check your biss screw as the o ring goes bad, and do a boost check because the gaskets around the throttle body go bad along with throttle body shaft seals.

 

[ktmrider]

Quoting Dopeem1:
I went based off the guide on vfaq and only thing i have not done in rip into fiav yet...

Thanks again guys!!

Did you follow the ENTIRE vfaq "Idle Surge" process start to finish?

The ISC is easy to check ( 4x ohm/resistance readings ). A bad ISC, especially one with short circuits/zero resistance, will wipe out the ECU drivers for the ISC circuit. So if all the resistance checks were at or near 31 ohms the original ISC was not defective. And sadly as it's an electronic part you won't be able to return it.

And it can be a vicious cycle, bad ECU drivers will take out a good ISC too.

I'd restart with a known good ISC then work your way down ( boost leak check, ECU swap, FIAV blockoff ).

 

[vr4play]

I would start with checking the BISS screw and then the FIAV. My car used to surge and nothing would fix it until I blocked off the FIAV.

 

[jogalant]

When you get sick and tired of it all:

Buy this

then follow this:

Click.

Problem solved forever. You live in a cold climate State so you will have to help the car warmup during the cold months. I'm looking around for an old school manual choke cable for this. After warmup idle will be rock steady all the time. If you have ac and aftermarket cams, I found a neat device that engages the ac compressor clutch at 2000 rpm and disengages it at 1800. Good luck.

 

[Dopeem1]

Well turns out the new sensor was defective. I tore the stock sensor apart, cleaned all the rust off all the terminals and WALA! Idles like new /ubbthreads/images/graemlins/smile.gif

Bruno, i am well aware of what i need, no need to keep repeating yourself. Remeber that once there was a time when all the was was afc's and the worked fine. As for the bov, like stated in my other thread, it will be getting a new fmic setup and a my hks bov. So in other words. Stop hating as ive owned the car for less than a week.

 

[tsitalon1]

What sensor are you talking about?

 

[Brunoboy]

Quoting Dopeem1:
Well turns out the new sensor was defective. I tore the stock sensor apart, cleaned all the rust off all the terminals and WALA! Idles like new /ubbthreads/images/graemlins/smile.gif

Bruno, i am well aware of what i need, no need to keep repeating yourself. Remeber that once there was a time when all the was was afc's and the worked fine. As for the bov, like stated in my other thread, it will be getting a new fmic setup and a my hks bov. So in other words. Stop hating as ive owned the car for less than a week.



Not hating, keeping the unknowledgeable knowledgeable. If you haven't figure out yet, this forum is very close knit. Anyways I've done the SAFC with my old GSX. You need to get a pocket logger or something to read knock, timing and all that.

 

[BpuVR4]

Autozone sells isc's??

 

[Steve885]

I bought one from CRAPA and it was mitsu OEM.