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I own a 1994 roadmaster estate wagon changed motors for a 1996, crank sensor is on new motor on front of timing cover the other didn't have sinsor. He


New member
Buick Ownership
2002 Park ave, 1996 RMSL, 1995 RMSL, 1995 RMS, 1992 Lesabre (My first, That some BMW totaled)
I could be wrong but if you're swapping from a 1996, then it will have a crank sensor to comply with OBDII emissions. 1995 (my model) and down used OBDI emissions, and instead of having the crank sensor on the timing cover by the crankshaft, they basically used the information sent by the optispark to provide the same effect as a crank sensor. So if you're reusing the same PCM and harness from your 1994 you may find that you shouldn't have to plug this in for it to run, although if you're swapping PCM's you will either need the harness from the 96 or run a wire. (Not even sure if you can swap PCM.) Again, I've swapped and played with old school 350's but I don't know half as much as some people on here, these computer controlled car can be tricky so someone correct me if any of this was wrong.


Full Member
Buick Ownership
1996 Roadmaster Limited Collectors Edition 58k - 1996 PAU
I also think, if you leave the CKPS disconnected, the engine/PCM would not know what was the year the engine that was installed. It's the same engine, with different PCM's and sensors. Why will it not start? Do you have have fuel pressure, spark, or is the starter not turning over. A Lot of questions need to be answered,


New member
Buick Ownership
Roadmaster Estate (1996)
When you put the newer motor in, did you make sure to get all the wires going to the proper plugs, and the proper spot on the OptiSpark?
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