i just bought another 90 civic si .. and the engine doesnt want to start when its warm out? is there anything i could do to help this..?

it starts perfect in the cold.. only on hot days it will do that

 

Possibly main relay. When you turn the key on, before cranking the motor, do you hear the fuel pump buzzing? If not, it may be the main relay, which is an easy fix.

 

the main relay would do that when its warm out?
never heard of that .. but i have a new one in the box... ill try that out

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by knightsef-eg &raquo;</TD></TR><TR><TD CLASS="quote">the main relay would do that when its warm out?</TD></TR></TABLE>

Yes, it is a well known problem with c. 1990 Hondas. See discussion under http://www.tegger.com/hondafaq/faq.html#startrun

If you are at all handy, re-soldering is easy. I just bought a spiffy new de-soldering tool, too, from Radio Shack for $11. Works great.