Misfire / rough idle

[Niko Jackson]

I’ve been chasing down an engine noise and it led me to taking off the valve cover. After putting everything back on I have had a rough idle and a misfire on cylinder 2, most likely caused by me pulling on the spark plug boot too hard. I replaced the wire the misfire code hasn’t come back but the rough idle still persists. It is most evident when I put it in gear, like a low rumble with a lot of engine movement. I have triple checked the vacuum lines and I’m at a loss. Any ideas?

 

[Niko Jackson]

I’ve been chasing down an engine noise and it led me to taking off the valve cover. After putting everything back on I have had a rough idle and a misfire on cylinder 2, most likely caused by me pulling on the spark plug boot too hard. I replaced the wire the misfire code hasn’t come back but the rough idle still persists. It is most evident when I put it in gear, like a low rumble with a lot of engine movement. I have triple checked the vacuum lines and I’m at a loss. Any ideas?

1995 FZJ80 1FZ-FE

 

[Niko Jackson]

Ended up being a bad injector connector.

 

[landtank]

I had something similar. I changed out the injectors. And afterwards I was getting a misfire 300. Turned out some oil had dripped into the injector electrical connector. Flushed it some cleaner.

The oil was from the intake as I’m boosted and running the original engine with over 333k on it.

 

[Niko Jackson]

I had something similar. I changed out the injectors. And afterwards I was getting a misfire 300. Turned out some oil had dripped into the injector electrical connector. Flushed it some cleaner.

The oil was from the intake as I’m boosted and running the original engine with over 333k on it.

Mine was due to the clip on the connector being broken and one of the pins sustaining damage. While doing that I pulled the throttle body off for more access to the wiring harness and noticed my cylinder #4 connecter was in the same shape. Will be replacing that soon. What cleaner did you use? Would dialectic grease be a good way to keep a good connection and contaminates out?

 

[landtank]

Electronic spray You want the connectors clean no grease. They are designed to be water tight.