'90 300 N/A idle woes

[nomadlife]

Hey guys,

I am helping a friend with his 300Z. It is a N/A with Auto trans. When the O/D is engaged and the throttle is let of from higher RPM, it comes down below idle and will occasionally die. With O/D off, this never occurs.Right now I have him driving w/o O/D and only engaging at freeway or over 50. Any suggestions, the only thought I had was, it might be in the computer; if it is is there a better solution than getting OEM?Thanks.

[izmyttz]

i had a similar problem...it was the plugs on my coil packs ...they were bad and didn't make a good connection so it was mis firing and caused it to idle high...not sure if this is your problem..but hope it helps