99 dodge ram 3500 van dreaded 0505 code

[joedogs]

i have a 99 ram 3500 van.with a 360 engine and around 65.000 miles.i also have the dreaded p0505 trouble code with a constant check engine light on.i have tried pretty much everything i have found on this and other site to help fix the problem.(checking and cleaning connections,inc pin connection to and from the pcm.replacing,tps,both 02 sensors,iac and cleaning the area where it goes.checking all vacuum hoses and connections all grounds).still no change.i can clear the codes with my cheap scanner and turn the light off.but once i start it up again the light is right back on.sometimes i don't even have to start it just turning it to the on position will put the light back on.through all this the van runs fine and idols pretty well(maybe a bit low but this could be my imagination).this would not even bother me but my state inspection is due and im pretty sure its gonna fail because of this.there is one thing.i dont know if this makes a difference.but when i use my scanner. when it reads(CAT) it always say not ready.all others come out either ready or n/a.no matter how much i drive it this never seems to be ready.local auto parts guy says only other thing is to replace pcm.(of course he has no way of checking mine)any help before i spend another 300+ bucks would be appreciated.

[alloro]

Turn your key to the on position. Use your scanner to clear the code and turn the light off. While leaving the key on, disconnect the negative battery cable for about 10 minutes. Then turn the key off and reconnect the battery.

The reason you might be having this problem is that the PCM is trying to regulate the idle with the information stored while the old IAC was in there. Doing the above procedure will erase the stored information and allow the PCM to relearn the idle. The engine might run rough for a day or so while this relearning process is going on.

[joedogs]

thanks for the help.but no luck.still doing the same thing.any other suggestions are welcome.

[alloro]

Then you might indeed be looking at replacing the PCM. Get the number off of the PCM and check the following link, you might find it to be considerably less expensive.
http://search.stores.ebay.com/Auto-C...610598QQsofpZ0