Ok i started a thread about my car not starting at all yesterday. When i was working on the car earlier and took the crank sensor out i realized that the new engine i got in the car i a 2002 engine. Question is simple, can i use that engine with the 2004 computer and wires or is it imposssible to achieve? ive managed to put the know sensor on the block and everything else is in place. but the engine still wont start.

 

IIRC, 2000-2002 and 2003-2005 (NGC) engines have a bit different wiring to certain sensors and a couple of sensors read differently. I don't get why your 2002 car would have a 2004 computer though?

 

Well, theres a miss understanding, my car is a 2004 sxt and the engine i bought it from motor master(a local store). They sold the engine as if it was 2004 and it does look like because of the valve cover and the crank cover. I didnt realize it wasnt till it was way too late. But then again if i must take the engine out so be it then. Thing is everything is in place already and i didnt want to take the engine out again to bring it there so it can be changed. Only sensor that doesnt belong to the old engine right now is the crank sensor(I know one of the most important i know). Anyways if the case is that i cant keep it ill bring it back to them. I just wanted to know if there was anyway to keep that one .

 

Also to be exact, the issue im having right now after spending some time today checking for problems is that the crank sensor is not receiving any voltage from the PCM while the cam sensor is. I think that is causing the PCM to shutdown the ASD. But then again, if the case is that i solve that crank sensor voltage issue the PCM will still not get a good read. I will take the engine out then. Just didnt want to take apart that again to start the process again. Thanks in advance for your help!!!

 

Well, today when i logged in to check for new replies i have realized theres something very wrong with the thread title. It should say 2004 Neon with a 2002 engine. Anyways im looking for a 2003\2005 engine since i realize that the older crank sensor works with 8volts and the newer ones will work with 5volts. Also theres almost a quarter of an inch difference between the length of the older crankshaft sensor and the newer ones. I guess the older ones can fit inside the newer engines using some kind of spacer but the newer ones will not work on the older engines since it should be closer to the shaft and i wont be able to achieve that. So im going to buy a 2003\2005 engine if i cant find a solution for that asap.

 

The thread title is why I was wondering why you had a 2004 computer in your 2002. I can change it for you though.

 

You were right on everything about the crankshaft sensor. In fact thats why i asked because you guys have a lot more knowledge than me about those cars . Older sensor works with 8 volts instead of 5. And the length of the sensor also is different. Like i said maybe people can use the older sensor with a proper spacer on the 2003\2005 blocks but i dont think it can be done the other way around. So im going to buy a 2003\2005 engine for my car then. Thanks a lot for your help!!

 

Yeah, it's one of those unfortunate things where mfr's "have to" mess with things for no reason. I have no idea if there is a workaround for it unless you can get the correct sensor and then give it a direct 12V and get some kind of electrical...resistor is it (?) to knock the 12V down to 8V.

 

Yeah the thing is(my everyday job is to work with electronics and it gives me the chance to deal with that kind of stuff pretty easily) im good at reading schematics and circuits and stuff like that. But, voltage might not be the issue here(i think i can solve that) but i will still have a shorter sensor since the older one is longer(the one that really belongs to the older engine). A 1/4 of an inch(give or take) longer. Thats why i rather go for a new engine. Maybe if i use the old crank sensor with that engine using a 5volt relay to get 12 volts and then a regulator to drop it to 8 volts. Maybe that way i could be able to get something.
But then again, im not too sure about this but i read somewhere that the distance between that crankshaft and the sensor should be around 0.050 of an inch which makes a 1/4 inch way too much distance to cover and get good readings. Im not shure about this also, but i also read somewhere that the older crankshaft sensor gives 7 beats per second and the new ones(2003\2005) will give 30 per second. So at the end i think even if i manage to solve the voltage compatibility issue i will still not get good readings to my 2004 PCM because of the distance gap between the crankshaft and the crankshaft sensor. I will try it anyways just for the fun of it and let you know what happened .

 

Regulator, there you go. I was suggesting getting the correct sensor and doing the wiring. It was just an idea as I don't know anyone that has found a right way to do this swap. You would know better than I in this case, so go with what you feel is right. Good luck!