INFORMATION ON BAC, IAC, AND ISC

[onlydriveford@aol.com]

I HAVE BEEN SEARCHING TO FIND ANSWERS ABOUT MY HIGH IDLE AND KEEP SEEING BAC, ISC, AND IAC VALVES FOR POSSIBLE ANSWERS, BUT CANNOT EVER FIND SPECIFIC INFO ON WHAT THEY DO, WHERE THEY ARE, ETC. AND WOULD LIKE TO HAVE A CHANCE TO FIX MYSELF BEFORE TAKING TO A SHOP IN EXACTLY ONE WEEK, WHEN MY APPOINTMENT IS. AS MENTIONED BEFORE, I HAVE NO EXPERIENCE WITH THESE SMALLER FOREIGN MOTORS AND AM FAIRLY INCOMPETENT SINCE I QUIT DRIVING MY TRUCK, ANY HELP IS DEEPLY APPRECIATED.

[Netopia]

Your IAC valbe is on your vavle cover on the right side right behide your dis. cap
When that act's up your car will run like **** and when it goes out it will notr crank at all.
Try spraying your intake out with some seafoam or some throtle body cleaner and see how it run's.
Check your PCV Valve behind your upper manifold to see if it's bad it's a a bitch to get to the hose might be done or the pcv might need to cleaned or replaced

[ginman999@yahoo.com]

I HAVE BEEN SEARCHING TO FIND ANSWERS ABOUT MY HIGH IDLE AND KEEP SEEING BACK, ISAC, AND AC VALVES FOR POSSIBLE ANSWERS, BUT CANNOT EVER FIND SPECIFIC INFO ON WHAT THEY DO, WHERE THEY ARE, ETC. AND WOULD LIKE TO HAVE A CHANCE TO FIX MYSELF BEFORE TAKING TO A SHOP IN EXACTLY ONE WEEK, WHEN MY APPOINTMENT IS. AS MENTIONED BEFORE, I HAVE NO EXPERIENCE WITH THESE SMALLER FOREIGN MOTORS AND AM FAIRLY INCOMPETENT SINCE I QUIT DRIVING MY TRUCK, ANY HELP IS DEEPLY APPRECIATED.[/b]

I just replaced mine. $40 from the junk yard $500 from Mazda. It does two things, makes motor run with higher idle till warm and adjusts idle under different load conditions. My motor wouldn't idle while in gear. 3 nuts, 2 coolant lines, 1 electrical connector and one air hose to take the thing off, very easy. It connects the intake manifold and throttle body.

[Netopia]

I just replaced mine. $40 from the junk yard $500 from Mazda. It does two things, makes motor run with higher idle till warm and adjusts idle under different load conditions. My motor wouldn't idle while in gear. 3 nuts, 2 coolant lines, 1 electrical connector and one air hose to take the thing off, very easy. It connects the intake manifold and throttle body.[/b]

Yeah there a pain when they act up

[old929guy]

I have 2 89's, US version. One runs great (150K) the other has a very high and fluctuating idle when cold. I plan to swap in order, the MAF, The bac isc, the TPS to see what's hurting the other 929. It has only 55K miles and should be running better. Once I find the PCV valve I plan to get two new ones for the cars. Both cars are heavily used miles-wise with long commutes. The hi mileage one needs struts like NOW. Going to convert to non-adjustable Gabs or Monroe.

[ithaj0kai@live.com]

I have 2 89's, US version. One runs great (150K) the other has a very high and fluctuating idle when cold. I plan to swap in order, the MAF, The bac isc, the TPS to see what's hurting the other 929. It has only 55K miles and should be running better. Once I find the PCV valve I plan to get two new ones for the cars. Both cars are heavily used miles-wise with long commutes. The hi mileage one needs struts like NOW. Going to convert to non-adjustable Gabs or Monroe.[/b]

I have this exact same problem.

My car likes to idle @ 1900 rpms in Park and neutral. But when in drive and reverse it will idle @ 800 rpms. After warming up, the motor will start fluctuating from 1900-2200 rpms. And it will do that until I shut it off and let it cool down.

I searched for intake leaks and found nothing, has anyone had this problem and found a solution?

[ithaj0kai@live.com]

Also, can I eliminate the bac? If its causing my problems and it only helps colds starts, I dont need it.

So is there anyway I can just block it off?

*EDIT*

I took off the BACV today, and put a sandwhich plate between it and the manifold. The car would start, but would shut off if I did not hold the gas down.

Maybe adjusting the idle or timing may allow it to work, but I didnt want to do that.