Deceleration air valve question
 

i noticed that my auxilliary air regulator vacuum line is not connected to the deceleration air valve. the line has been plugged and is just lying there.

At some point a PO did this. I also do not have an O2 sensor.

does one have something to do with the other and what is the purpose of these mods?

Should I leave the line as is?

Leave as-is
 

Both are very common alterations for the SC. The decel valve has been known to annoyingly hold the revs up for 2-3 seconds following coming off the throttle (by design) which many don't like. High idle problems also caused by it as well in some cases. Was put in for emissions reasons.

O2 - some say their SC runs better without it; some say they stick with it. My SC definitely runs better without it connected and I have done many experiments with it both connected and disconnected at various mixture settings.

My SC has both decel plugged and O2 disconnected by choice. I am a big believer in staying stock but these 2 things are better off disabled in my case. The car simply runs better and fits my preference for crisp revs (with no decel valve).

What you have is very common for SCs. If it runs well and you are happy with it, I say leave it alone.

thank you. this is helpful. i posted a thread last week about my not having an O2 sensor and got no response. youve answered both questions i had. ill leave it alone since im happy with performance

Do you get awful gas mileage? My O2 was disconnected when I went with SSIs and a 2in2out, and I am happy to get 15mpg. As far as the decel valve, the car drops revs so quickly that it will occasionally sputter and die when cold. Is that related? I love the throttle response, but it makes for a fussy cold car.

not sure what the gas mileage is. its not too good, maybe 18-20..

mine doesnt sputter and die, but for the first few minutes when cold started, its definately a little fussy, but warms up quickly and smooths out. thats been my experience with air-cooled motors with motorcycles. so far it has not been anything i would call abnormal.

maybe you have something else going on?

note: my exhaust is stock, except a cat bypass

Trotskyite and SCRandallf,

If you are having warmup problems, you might want to check out the functioning of your WUR. If you are getting poor mileage, check your CO setting.

Paul, hello from across the lake. has it rained every day up there? ive never seen such a rainy summer here.

:mad: