Ok, I purchased a 95 164k automatic a little over a week ago and has had minor starting problems when i bought it. It would crank but wont turn over. Once it started it ran fine. The second day after the purchase the car died while at a red light. It would crank but die even when i pressed the gas. I bought a new battery and got a tune-up as a start to repair the problem. With the new battery the car started up.

The day after i got my tune-up the mechanic told me that there were two different computers in the car (mis-matched) and that I need to get the correct number from Nissan, and that this was the cause of the car starting issue.

I took the car made a few stops and everything was fine. Until, i made one stop and was only gone for ten mins, i turned the key and the car would not crank. The exterior/interior lights still worked when put on. I re-adjusted the gears from park thinking it maynot have been fully in park. . .still nothing. I tried giving the battery a jump and it sounded like a dead battery. It was like as if it didnt have enough power to crank.

1. Could this be my alternator draining my battery?

2. What is the mechanic talking about two mis-matched ECU's? Is that possible?

3. I've searched our site, many members changed their ECU's, does mine need to be reprogrammed or something? TIA.

 

well i can be wrong, but the way you explain it, makes me think the car has in two computers....i only know of the ecu(1), so the most i can think now is that the ecu is for a different car or model.......try reaching the stealership man>>or wait for more orgers to tune in.

 

the mechanic told me that the starter is the problem but my engine light still comes on. i'll try to do a self-diagnostic and see what it says.

 

If you bought it from a used car lot, take it back and have them fix it.

The two mix matched ECU thing doesn't make any sense, or you're not explaining it very good. When the mechanic told you that, you should have drilled him and asked which specific "ECU's" he's talking about.

If you're concerned about the alternator (or battery), take it to Autozone and have them test it for free.

 

Its probably the Alternator like "The Wizard" said take it to Auto zone as far as mismatched ecu's I really drought it because I change my ecu out from 98 to a 95. Had it there for almost 2 years now No problem yet.

 

what did you get from doing that.?

 

Prolly avoiding obdII

 

Well avoiding ODBII for one, so most of the 98 emissions i don't need so that saves space and since I have a 3.5 swap there is no codes regarding anything.

 

Naw i aint buy it from a car lot, a private owner. After the mechanic told me i had two computers and i need to go to Nissan to get the correct number, I checked and only had one computer in the car. . .so i left. A few hours later the car wouldnt start. The battery was new i had bought a few days ago from autozone.

But i found out that my starter was bad and had it replaced, it starts up now but kinda rough and the engine light stayed on. So today, I took it to autozone for the diagnostic test and was told it was for a crankshaft position sensor.

Can i put that in myself? thanks yall

 

Yes, the cranshaft position sensor is extremely easy to replace.

 

I check the 4th Gen FAQ's and dont see a link or directions to replace it.

 

Well, you also need to know if it's the cps (REF) or the cps (POS). Most likely it's the cps (REF). Did Autozone give you the exact code so we can look it up for ya?

 

sorry i meant to mention that it is the CPS REF

 

You should first check the cps (REF). It could be as simple as cleaning it. The cps could be caked with grease and gunk reducing its magnets efficiency to pick up what it needs to. It's located next to the cranshaft pulley. Pull off your passenger front wheel for easy access.

 

The 95 ECU *IS* OBDII.

 

Your right it is easy to get to. I just went to go check it out there is a lot of gunk down there, the cps is clean but the plug that goes into the cps does not snap into place, it comes loose will a little pull. Maybe i need to change the wire first before i buy another cps, would that be difficult to replace?

 

IIRC, the cps harness is part of the engine main harness and can't be bought seperately. How does the harness/plug look? Dirty? Mangled at all? If they appear to be in good condition I wouldn't worry about it and focus your attention on getting the plug to snap and stay in place. Clean the plug really good with some C&R electrical connector cleaner (sold at Autozone and the like); as a loose/dirty plug could very well be the cause of your problem.

I don't have a FSM or repair manual in front of me, but I believe the cps sensor can be checked with a multimeter to see if it's within spec.

 

it looks like it may need some cleaning but i dont have a multimeter check my cps, i may have to buy a new cps and see what happens. If it works then its not the wire, if it doesnt then the wire harness will be next to replace.

Does a new cps come with the wire hareness? Where can i get cps wiring if i need to replace it?

 

Man i just noticed that i got the crankshaft position sensor to change as well as the electrical circuit for the camshaft sensor.

Now how do i get the wiring for a crankshaft position sensor (just in case i need it) and the wiring for the camshaft sensor, anybody know? and can i do that myself like the crankshaft position sensor?