Chrysler Repair: high idle speed 3.3L V6, fuel pressure regulator, vacuum lines

Question
My car, a 1993 Eagle Vision 3.3L V6,  173000 miles.    Was running fine but was leaking gas.  After repeated visits to the dealer and having all the fuel injectors and the fuel pressure regulator replaced it no longer leaks gas, but idles about 1500 rpm (you'd think the techs would have noticed this)  I refuse to take it back to them as they have enough of my money.  I've checked a few vacuum lines and replaced one with not much diference in idle speed.  Since there appears to be no mechanical way to reduce the idle speed I need to know what to do?  I'm sure I could replace the IAC or the TPS if I knew if that was the problem.  Any help appreciated.  I think this car has a lot of good miles left in it.  Thanx!  

Answer
Hi Al,
I hope to help you get this resolved. Looking for a vaccum leak is a good idea. But it also could be one of the sensors or actuators operated by the engine controller. You will be able to do a self-diagnostic test that will help identify the reason because up thru the mid 90's the engine controller had a memory which stored engine fault observations as codes that the owner could readout without special instruments.  Begin a readout as follows: Take your ignition key and turn the ignition switch "on-off-on-off-on" and leave it "on". Do this switching quickly so that no more than 5 seconds elapses. Then watch the 'check engine' light to begin to flash, pause, flash, pause, etc. Count the number of flashes before each pause and make a note of them in the order that they come. The last two flash groups will be 5 in each. Repeat the readout until you have the numbers accurately (the same result, two times in a row). Then pair the numbers two at a time in the order they came, to form two-digit numbers, for example the last number will be 55 which is the code for "end of readout". Then write back and tell me the other numbers that came out and I'll see if any of them are related to your problem. You can also go to the Allpar site for code number translations:
http://www.allpar.com/fix/codes.html
I'll be tied up today so I Can't get back to until the evening.
Roland