I still get a high idle rpm at 2K or sumtimes 1500 in a warm day, we adjusted the BAC valve all the way but we cant lower it any more, what else can we adjust?

 

The fast warm up cam thermo-wax may not be backing off.

Throttle stops- both secondary & primary.

 

Set the TPS and if the idle stays high you must adjust the small screw w/ the 8mm locknut.

 

TPS first?

 

The operation of the thermowax should be checked first. If it's not backing off as SureShot suggested, playing with the throttle stop screw will have no effect. It will stuff up the warm idle once the thermowax is fixed though.

 

make sure you have some slack in the throttle and cruise cables and they aren't holding it open.

 

i have all the slack i can give! ill check TPS, BAC valve might need to be cleaned

 

Question: what if i dont have new gaskets for bAC valve or gasket maker? how bad is it to re-use the onld gaskets for this particular application?

 

You can get away with it sometimes, it all depends on condition. If they don't seal right, you'll be able to tell there is a vac. leak.

 

OK i took out the BAC valve and the tube where the 2 hoses that flow coolant were clogged, i cleaned it and sprayed it all with carb cleaner. the coolant flows, but when i blow through the tube where the thick air hose goes, it doesnt blow through, i think it may be clogged. it it supposed to be like this?

When i started, my idle was 1300 then back to 2000! damn!

 

When the bac is off you should not be able to blow thru it. Yours sounds like it's ok.

This is a non-turbo car???

The water passage was clogged??? The bac does not depend on the water passage being clogged/not clogged.....BUT that water passage/hoses come from the thermowax area of the throttle body. It's a indication that the water passage in the thermowax is possibly clogged meaning it'll take quite some time for the thremowax to react to a warm engine.

So back to the above posts about setting/checking out the thermowax/ fast idle cam on the back of the throttle body. YOU must remove the throttle body to examine this area.

On the other hand, with the engine idling and fully warmed up, if you reach over to the throttle linkage near the tps....can you apply pressure to the linkage towards the CLOSED position and make the rpms drop significantly????? That shouldn't take but a few minutes to check out. What happened?

 

I have an NA and when i took off the BAC (passengers side) there is a connection where a hose connects to it and out to another hose that connects to it on the other side. this was completely clogged.

When it was taken out the part where the big hose goes (i think air is suposed to flow through) i couldnt blow through it. is it normal, if its not this

then ill have to check the thermowax, thats what my dad thinks it is too. any way to fix it?

 

No you should not be able to blow thru where the air hose connects to the bac. It's off, so its shut.

Did you try idling the engine and pressing the throttle linkage towards the shut position to see if it made a difference?

 

still idles high but 1300-1500... i messed with the cable nothing.

BAC valve is fine...

I messed with the TPS and got it lower, but is there a way I can adjust the TPS?