New Motor Idle Help

[phantom90333]

I went from a stock block with aem short ram to the build below. I just finished putting everything together and fired it up and I am having some problems.

ERL 2.1L K20 block with 9.0:1 pistons

Supertech Valves, Seats, Seals, Guides, Springs and Rentainers

New guides and chains and hybrid racing tensioner

ERL S2000 Oil pump

Hytech Cam tower mod

Kpro using stock K20 basemap

RBC Intake Manifold

Hybrid Racing 70mm Throttle Body

Stock Cams


So the issues I am having are as follows.

The car warms up fine to an idle bout 900 rpm but it starts to jump around to about 1200 rpm every now and then. I cleaned the IACV twice and it is not the cause.

The real issue is after letting it warm up. I give it some throttle, about 15-20 percent from the TPS sensor and it doesn't come back down the whole way. It stops around 1300 rpm and there is a rattling noise coming from what sounds like the valve cover. It also showed my ignition degree at 30 degrees as it wasn't coming down. The valve cover seems really hot but I remember it being somewhat hot before. The car has been in progress building for the last year with motor out. The car is up on jack stands now until I can figure this out. Any ideas?

[Arno]

I cleaned the IACV twice and it is not the cause.

Try taking it apart completely and then cleaning and lightly oiling the bearings for the IACV. So far my experience has been that if there's the slightest roughness or feeling of 'catching' on the IACV shutter mechanism then it won't work reliably. Can be pretty annoying..

Also check with some brake or carb cleaner around the various flanges and mating surfaces for air leaks. (idle speed tends to change if there's a leak and you hit it with the spray)

It sounds a lot like there's un-metered air leaking into the engine. Does the MAP reading remain high when the idle is high?

Do you still have the thermostat air bypass system installed on the engine or is it removed and the connection plugged on the intake manifold? If it's left open then it's probably still OK warming up, but when it's warm it's letting in too much air.

Bye, Arno.