1993 wont start, 4 codes

I fired up the car after it was sitting for a few weeks, it started immediately then stalled, then it wouldnt start again. Engine cranks fine but thats about it.
I pulled codes:
17 - RPM signal problem
18 - Cranshaft position sensor circuit open or no signal
34 - MAF sensor signal or circuit problem
42 - ignition system problem - electric spark timing circuit fault

Sure sounds like I have an electrical problem, but do these 4 shine a light on something to look at right away?

Well the cps looks like the issue here. Check for spark and injector pulse, if none I would replace the crank sensor. The ign module could be an issue also, it can be tested at most parts houses. Also check the wires from the cps to icm.

I am going with the ICM being the culprit as everything seems to be pointing in that direction. What I don't understand though is why ebay has them for $35 while Rockauto ranges from $100 - $200? I have no problem paying extra, but if it is just wasted money and I am getting the same part and functionality, I'd rather not. Anyone have experience buying one of these yet?

http://cgi.ebay.com/ebaymotors/NEW-IGNITION-MODULE-1995-2002-CHEVY-CAMARO-D1977A-LX364_W0QQcmdZViewItemQQhashZitem588289d551QQitemZ 380147193169QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAc cessories

yes i know it says Camaro, but the part# is what is important, and this is supposedly equivalent to AC Delco D1977A, which is what i need.

Well I am happy to report that the ignition control module was the issue! Very happy with this diagnosis, didn't throw unnecessary parts at it and tackled it the systematic way. Once I threw in the $40 part I mentioned in the previous post, it fired right up. Hopefully this part is of the same quality as the dealer module which goes for over $300, or the rockauto ones which are around $100. Amazing how much markup there is on these parts.

All I have now is Code 23, IAT sensor circuit. It's reading -40F, so its either disconnected or faulty.
I sure wish diagnosing the Ford Probes was this easy, they are a nightmare. I have two.
Update - the IAT was disconnected, most likely by Aamco when the transmission was replaced in February and I didn't notice it.

Great glad to hear the issues are resolved, feels good right?

Yeah sure does. and to think some people would just assume their 16 year old car finally bit the dust when it acts like this, and junk it.