Need opinion on codes

[JeffM T/A GT]

My car had been acting funny for a few months now. It would run great for about 15 mins or so then die (No missing or hesitation even at wot). If I let it sit for an hour or so it would start right up but only for about 15 mins. Now it won't start at all, just cranks. I had It scanned and it gave 3 codes 16, 36, and 42. The mechanic that scanned it told me those codes all go back to a short in the pcm. I posted this at z28.com and everyone seemed to think it was the opti. Just wanted to see what you guys thought. I would much rather pay 150 for a used pcm than 300+ for a new opti.

[BrdWAtti2d]

Ok your codes don't make sense, they are five digit codes starting with a letter, usually P, like P0141. If you find that you do need an opti you need to shop around more. $300.00 is on the steep side, original AC/Delco opti's can be had for a lot less.

[3800_Firebird]

^^These are OBDI codes, not OBDII's.

42 sounds serious. In my Haynes 92-02 F-body, it is described as Ignition Control Circuit. Short between ECM/PCM and Ignition module. Options are replace either of those parts, check for shorts in the wire.

[BrdWAtti2d]

Oops my bad, didn't notice it was a 94.

[Craig 94 TA GT]

16 and 36 are usually opti related. It really sounds like opti symptoms to me. Rob (shoebox) has a nice tutorial of testing the opti. Try it when it dies...http://shbox.com/1/4th_gen_tech2.html#opti_test

[Rob B (shoebox)]

42 often accompanies 16 and 32. Sounds like opti or opti connection. The PCM is what I would suspect last.

[Injuneer]

16 and 36 are ALWAYS Opti related. The PCM is not seeing the high and low res pulse patterns from the optical sensor. It can run with DTC 36 (high res missing), but when DTC 16 (low res missing) sets it shuts down the fuel system. As Rob pointed out, could be the connectors for the Opti harness. Check them for corrosion or camaged pins.

42 is the IC module, but can also be related to the Opti, the coil or the PCM.