So a couple days ago I bought a 05 350 Z everything seem to be fine with it when I test drove it before I bought it. When I got halfway back home with it I pulled over to a gas station to grab a drink got back in and it went in limp mode. I checked the battery and the battery was three years old so I figured I’d replace it and the new battery got me all the way home. Drove it around for a little bit parked it hopped back in it a couple hours later and I was having the same problem with the new battery. The car was in limp mode figured it would be the alternator went out so I replaced it and warranty the battery so brand new starter and on a second brand new battery drove it around the next day and I still run into the same problem. Does anybody know what could cause this issue?

 

When you say "limp mode", are you referring to engine running condition of not being able to rev over 2k rpm? That's limp mode. Sounds you're talking about a non-start due to a battery connection issue.

If this is the case, the first things to check are your battery connections. Not just the battery terminal connections but importantly, your ground cable. Check to make sure it isn't self destructing (ask me how I know) but equally important, the ground connection on the side panel wall. May need to freshen up that connection. I didn't mention the starter side connection since I'm assuming you freshened up that connection with the new starter.

If that doesn't cure it, the next step is to try and jump it so you can get it to a shop to have them load test the electrical system to pinpoint the electrical gremlin instead of throwing parts at it.

 

I have replaced the negative terminal because the negative terminal was loose when I got it but I’m still running into issues. The starter is fine from what I can tell. The previous owner installed an aftermarket radio that has a DVD player into it. I found out last night that it has a parking brake wire I assume that’s too plug into the parking brake so that when the car is in park, you can then watch movies off the touchscreen but he rigged a switch underneath the dash I’m assuming it’s to trick the computer I think that the car is in park when it is not, but it’s only just a guess. I wouldn’t think it would draw as much power like it is I know the alternator is working like it should for. I have unplugged the negative terminal and let the car run off the alternator alone.

 

Does the car have any codes stored?

 

I'll ask again. When you say "limp mode", do you mean the car isn't starting? If that's the case, does the car even crank? (Doesn't sound like it.)

Did you go back and check the ground side of the negative cable as mentioned or did you just change the terminal clamp or the whole cable?

 

yes, the car starts but it won’t go past 1500 RPMs 2k RPMs

 

only a P0183

 

I'd have to refer to the FSM, but that could cause a limp mode. It's the little black thing with two wires on the fuel pump assembly. See pic below. I think it's only available with the pump.

 

Yep, that's the fuel tank temperature sensor. Attached is the FSM section.

 

I found out what the issue was apparently my “ mechanic experienced friend “left the positive cable to the alternator loose and the connector Half in. moral of the story. Double check your work.