Got a couple weird things happening...

88 350 TPI 700R4

1. cold start is never good... even with idle turned up a bit it still likes to try to idle at a bit over 500 rpm's... but idles around 1000 after driving for a while (warmed up)

2. cruise control is extremly choppy... it is anything from smooth... though it still keeps the car at the right speed... it's just very quick throttles that will make anyone with a weak stomach sea sick ...

3. what sounds like an open air hose coming from the heater control unit above the radio... but does not change or have any reference to whether the heat/ac is on or off...

first thought would be there's a vacuum leak of some sort... but i'm clueless on where to look for vacuum lines... as i have no experience in that area... or how to actually check them... (spray water on them and see if the car sputters?)

any help on any of these issues would be greatly appreciated... and any more info needed.. just let me know

Thanks!

 

Does sound like a vacuum leak

You can test the theory by popping the hood, then pulling one of the two vacuum lines just above the fuel pressure regulator on the passenger side of the plenum, the one that ISN'T connected to the regulator should be the vacuum line for the heater vents, then plug that hole and see if things respond differently

 

1. What do you mean turned up the idle? Only way to do that on a TPI is modify the chip. The ecm picks the idle.

2. Dont know. May be related to #1 and what I think you did to change the idle speed.

3. There's a vacuum switch under there. They have a tendency to leak. You can get in there fairly easy and check it out, and the part itself isnt too terribly expensive.

 

I concur with the vagabond from the wasteland. Your cruise control problem is related to the fact that you mistakenly bumped your min air screw way out to try to fix your idle problem. As max said, the computer picks your idle speed, period. If you try to take manual control by cranking the min air screw way in to completely override the IAC all you will do is cause a host of driveability problems. You need to figure out why your cold start is so bad. Being a MAF car, Vacuum leak(s) could be a real possibilty. Also a bad CTS.

 

However any vacuum leak significant enough to effect the operations would trip a code 44, even a minor one.

???