So I have about 35 miles on a fresh S4 N/A (sorta) rebuild I finished a couple weeks ago: 6 port end housings w/ functional aux sleeves, TII rotor housings and center plate, S5 N/A rotors, all new springs and seals, RA 2mm apex seals, RB steel flywheel, Corksport headers, ported TB.

My problem is that I can barely get the idle up to 800RPM. The idle screw is all the way out, the timing is good, fresh spark plugs and wires. It sounds like there is a minor exhaust leak, but I don't think that would cause the problem. I haven't used starting fluid to check for vacuum leaks, but again, I don't think that would cause the problem. The injectors were cleaned and balanced by RC engineering at the last rebuild, 60k miles ago. During the full life of the previous engine, I used quality premix and ran a bottle of fuel system cleaner through once a year or so. The only changes to the engine during the rebuild were the TII rotor housings, the flywheel and the headers. All other mods were on the previous build and worked great.

I'm thinking about pulling the TB and having at it with the air compressor. Maybe something got plugged up during the 8 months that she sat while I was waiting for funds.

Any other thoughts?

Thanks
Andy

 

adjsut the cam angle screw on your throttle body, or tighten your throttle cable but not to tight or it could go straight to red line why do you want to raise the idle
and rebuilt engines do like to idle at first

 

factory no-load idle speed is 750 warm...

 

Well, once the engine is broken in, I will want it to idle there, but right now I'd like to bump it up to 1000-1100 so that it won't stall at every 3rd stoplight.

Or maybe this will just be another reason I need to get better at heel-toe...