my car is a 77 2plus. she runs good all day then when i shut it down and restart it runs really rough for about a minute and a half and then cleans up and runs good. any help would be appreciated!

 

Welcome to ZDriver!

Have you checked the basics?
-Wires
-Plugs
-Dizzy cap & rotor
-Cold start valve
-Air regulator
-CHTS
-AFM
-EFI sensor wiring?

 

no CHTS on a 77 nismo. for shame....

 

Roger that.

 

id start with the basic tune up and cleaning all the connections even the ECU ones themselves seeing if any of the wires in the plugs are loose. its wierd it only does it for a minute AFTER its warm. makes me wonder if the air regulator and or cold start valve is acting up.

 

My car does that too!! usually when it's real warm out. It sounds like she's coughing up a fur ball, then spitts up and goes fine. it's like it's not running on all 6. I had a really good tune up and some connections to the injectors replaced, and it doesn't do it nearly so bad. I had talked to a z mechanic about it, and he thinks the fuel is getting too hot in that fuel rail, and not spraying properly... I really want to fix this problem too, I was going to try using this insulating stuff, but it's not an easy job.

 

Next time unplug the cold start valve, it's just behind the throttle body with a plug that looks like the injector plugs. If it runs okay then it's your thermister sensor located on the thermostat housing. If it's bad the ecu thinks the engine is cold and turns on the cold start valve. If that's not it check you sparkplugs to see if the are gas or oil fouled.

 

thanks for all your responses! most of the parts suggested to check are new within the last six months! the cold start valve idea sounds the most likly but i'm pretty sure it's plugged with some sort of goo. i'll give it a try though.as far as the thermister witch one one on the housing is witch? doesn't say in my Chilton. thanks again everyone!

 

finally got a chance to replace the thermotime switch and no more sputtering! thanks all for your help!