I recently swapped out a 3.7L engine in my Cherokee. I'm stuck with a crank no start. The only codes I'm throwing is a P0335 crankshaft position sensor.

I have ...
Replaced The CPS itself
Swapped All The Relays
Replaced The ECM
Checked All Fuses Multiple Times

I have Full Service Manual and have went through every test they give for a P0335 code and everything seems legit.

I'm getting 5v at the sensor connector. I'm getting 5v on the signal wire at the connector. Nothing is shorted. I pass all the resistance tests.

Another odd thing is my fuel pump is not running although when I directly connect it to 12v it runs just fine. I have replaced the fuel pump as well.

I don't know what else to do?

Any ideas?

 

Well I think I have it figured out. I'm betting it's the tone ring. Everything I see says the 4.7L went from a 16 tooth to a 32 tooth tone ring. I can't find much info on the 3.7L but I'll bet it's the same. Since the new engine is obviously the old design (no egr) I'm betting that the older tone ring is in it causing the crank sensor to not read correctly.

I'll know for sure in a day or so after I tear the engine down again. I'll update once it's done.