I have about 3.5 to 4 hours on my rebuilt S5T2. It idles perfectly at 1000 but if I try to drop it just to 950 the engine rpms will oscillate between 950 and 1300-1400. If I turn the idle back up to 1000 it smooths right out. After turning the rpm down I rechecked the tps and it still shows 1 V.

 

Cool. Glad to see another successful rebuild!

I assume you've probably eliminated the possibility of vacuum leaks...? You still have the BAC valve and emissions? Is the engine ported??

 

dude, it will have to be broken in and then the idle will start to lower. dont mess with the idle stuff at all.

 

Definitely no vacuum leaks. I still have the BAC but it is not connected(electrically) but all of the other emissions have been removed.
The engine is street ported.

 

OK, thanks. I haven't had it out of the garage yet but I've let it idle at about 1500 rpm for 4.5 -5 hours total.

ashley

 

Is your PCV venting to atmosphere? That will raise idle.

 

I don't recall ever seeing a PCV on my engine. Sure not like the typical PCVs found on piston engines any ways.

 

When I first started my street ported rebuilt engine, the idle was at about ~1,500-1,800 RPM for quite a few miles before I was able to successfully mess with the idle.

If you read here in Rotary Resurrection's "REBUILT ENGINE START-UP & BREAK-IN INFORMATION"


8) Once it is running and youre satisfied everything is stable, set the idle to around 1500rpm and let it be. Since compression is constantly changing, there isn't much use in adjusting and readjusting idle and TPS settings until breakin is almost complete, as the settings will change almost daily. Right now, the more you can drive it, the better. It is helpful for the first few hours to just let it idle in the driveway, if you cannot drive it around for whatever reason.