I have a 93 FD with a JDM tt motor swap and no other addtional mods. Car has a High idle and bouncing between 1100 rpm-1500 rpm constantly (Very annoying). I want to get it at 750 rpm as a idle. If I push down the clutch and put it in gear the rpm will drop to 1000rpm and stays constant without bouncing rpms. I assume its one of the many Vac lines. Where do I start? The engine did come with aftermarket silicone blue hoses. Please note I am in the RX7 scene for two months and I am learning by the day. I have posted in the past and some of those jargons confuses me. Please make it simple as possible for me so I can understand and if you have pictures diagrams please post them or email me them. Thanks so much!!

 

http://www.autosportracetech.com/RX-7/vacuum.jpg

also try spraying carb cleaner over the vacuum hoses (not too much) whenever the idle lowers thats, that will be the area there is a leak.

if you cant do that just have a professional do it. dont mess up your fd

 

Wow that diagram makes me dizzy ha ha! Should I pull off the intake manifold since most of the lines are under there? Also will carb cleaner eat up the hoses? I sprayed Carb cleaner on plastic once and it melted it sorta.

 

Start with the hose material.

There is a popular misconception that silicone hose is a good choice. That is not always true--note that silicone based hose does not hold up well when exposed oil and many VOC's. It gets soft and falls apart on its own--unlike the stockers, which harden and often break when disturbed.

A better choice (and best bang for the buck) is line made of Buna-N (nitrile) rubber. Some prefer Viton, and it does the job, but it is much more expensive and is overkill for the application.