Question about idle setting on sr.

[TheBigS_42]

I searched through a bunch of other topics on here and none seemed to have the exact same issues I did:

I decided to time my SR today and got myself a timing light and went at it using the FSM and advice from other peoples attempts. Using a piece of KA spark plug I managed to get a good signal and after following the procedure I think I managed to get into the timing mode after unplugging the TPS. However after it was unplugged the idle would not go below 1900. My idle has always been a bit high (1000 when warm), so I screwed in the plastic screw on the IACV and when it bottomed out I managed to get it down to about 800. After I checked the timing which happened to be spot on at that rpm I plugged the tps back in and it stayed nicely around 850.

My question is though, I assume that it isn't normal to have to tighten the IACV screw all the way? Does that mean it is dirty or what else could be wrong? My boost gauge is reading -20 vacuum so I dont think I have a major vacuum leak? Also it seems now, although it idles really nicely, when I step on the gas when in neutral it hesitates briefly before revving up. Only about a 1/4 second or so but it seems as though it is gasping for air if that makes any sense. Is that because of the IACV screw being all the way in?

The engine is essentially stock with nothing done other than a FMIC, exhaust and recirc BOV. (More info in my build thread in my sig)

Thanks!

[TheBigS_42]

Bump

[zachattack_5491]

Yeah you shouldn't have to put that screw all the way in. Based on my understanding (which may be completely wrong) it sounds like maybe the IACV is stuck open. -20 is good vacuum though, mine is only -14 and I can't figure out why The hesitation when you step on the gas is a symptom of IACV problems. I know exactly what you're talking about, and I've struggled with it for my whole life (KA and SR)

Anyways, hopefully someone with more info will chime in because I'm interested in some answers too.

[Hijacker]

It could just be that the IACV has some age on it and needs to be adjusted a bit further down. So long as it's working fine now, there's no need to worry. It could potentially need to be replaced down the line.

If you need to change it out, FRSport has one http://www.frsport.com/Nissan-OEM-S13-S ... _1123.html But that price is outrageous compared to what they were selling them for a couple years ago (used to be $150-ish). I prefer the updated part since it has a metal screw. I"ve seen too many of the plastic screws strip out from just age.

[TheBigS_42]

It does seem to be working mostly fine, its just the hesitant throttle stumble thats changed. Maybe its not a big enough problem to try and fix? I'm skeptical about trying to clean it as theres so many stories of people barely getting their car running after. $420 is pretty outrageous for a new one thats for sure. Any other thoughts?

[zachattack_5491]

It does seem to be working mostly fine, its just the hesitant throttle stumble thats changed. Maybe its not a big enough problem to try and fix? I'm skeptical about trying to clean it as theres so many stories of people barely getting their car running after. $420 is pretty outrageous for a new one thats for sure. Any other thoughts?

I pulled mine off of my KA and cleaned it. It was nice knowing for sure that it was clean and I had it set correctly. When it's off you can see exactly where the screws are and how far they are open. The only thing stopping me from cleaning the one on the sr is it's location. It looks like a serious PITA to get off.

[the converted]

Also make sure that the throttle plate is closing properly.