Help guys please! I got done tonight putting my car back together from doing valve cover gaskets and misc. other small things. When I cranked the car it had a nasty idle... obviously somthing wrong. It won't go away and the car runs like crap, almost certain 1 cyln. if not more isn't firing or injecting properly. I pulled the codes from the ecu, it gave me code 51, which is the Injector circuit code, the cause listed is: The injector circuit is open, it says to check Harness and connector Injectors. I checked over all my coil packs (yes all my coil packs work and i have new spark plugs) and over all the injector wires, everything seems to me fine. I have no idea what it could be or what to do. If anyone has any ideas or any recomendations please post them because I really need youre help guys (and girls). If you care enough and think that talking to me about the problem would help you determine what it is tell me and ill PM you my phone number... Thanks guys, I know if any forum can help me it is definatly this one, although this forum is small and slightly slow at times you guys are really helpful and I hope that I can be helpful in anyway I can in return, appreciate any/ all feedback,
Chris

 

If you just got done changing the valve cover gaskets, then you had to remove the upper plenum, correct? I'm thinkin maybe your firing order isn't correct. You might've mixed up the way the coil packs/connectors connect. Wires might've gotten mixed up. Recheck your wiring order.

 

If you're sure of all of your connections then you're going to need to check the continuity of all of your injectors and injector wires. After you run it for a coupla minutes, you can pull the plugs to see if any of them are wet. That might tell you if you have and injector stuck open or no spark to a cylinder.

 

I know my firing order is right simply because I labeled them and took a picture of them, then put them back exactly the way they were

 

Ok, good and bad news, the car runs now... I have bad wiring somwhere on the harness that runs to injectors/coil packs... If you shake around the wires the car runs great but somtimes It will have a horrible idle and terrible almost undrivable igition break down, I know courtesy nissan sells some of this harness but don't you have to re solder it?

 

I would check all of the connectors for corrosion and tightness first. ie: clean all of the pins and receptacles with a file or emery paper, then use some dielectric grease on them. Some people like to pressure wash / steam clean their engine bays ....... bad bad bad. on electrical connections and engine seals. Then tape all of the connectors. Then do a continuity check on all of the wires in the bundle that you're shaking to see if there is a bad wire. Ideally, move the harness until it starts to run bad and then shut if off and check. If you find a bad wire just replace it.

But, then again, if you want to spend the money on a new harness........