Besides the CAM sensor, the 94-newer 3.4 DOHC engines also had a 2nd crank position sensor (24x) that resides behind the harmonic balancer.
I know for a fact the OBD2 PCMs need to have the 24x crank sensor hooked up to them or they won't work right. I'm not 100% sure about the 94-95 OBD1.5 PCMs. Could be the same deal, but I have not had the opportunity to test it yet.
Therefore, if you have a 91-93 3.4 DOHC engine, the only PCM I recommend you use with it is a 91-93 3.4 DOHC PCM (SERV NO 16149396) which does NOT require the 24x crank or cam position sensors.
If you have a 94-newer 3.4 DOHC engine, you can still use the 91-93 OBD1 PCM on it. But if you have a 91-93 3.4 DOHC engine, you aren't going to be able to use a 94-newer PCM on it unless you can get the CAM and 24x crank sensors mounted and working properly.
OVERKILL IS UNDERRATED
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