I've posted about this in the F.I forum, but I'm wondering now if this may be an ecu fix.

1998 Integra LS, getting ready to turbo, full rebuild forged bottom end .2 compression higher(9.4:1), full supertech valve train, stage 2 cams, aem cam gears, all pumps, gaskets new. After the rebuild I'm having a problem with RPM's dropping VERY fast and too low when it gets hot and I push the clutch in or come to a stop, it goes so low the oil pressure light will flash because the pump wont spin fast enough. This only happens once it gets hot. Bearing clearances rechecked and they are fine, new OEM pump in just to be sure. I'm still running the stock ecu, so I'm not sure if it's a mechanical problem or the ECU not knowing what to do with all these new parts. Is there a way to "tell" the car not to let the RPM's ever go that low with hondata s300?
Thanks!

 

Can you raise the idle with hondata? yes, is that going to fix your problem, maybe. Sounds like you might have a vacuum leak try messing with the idle control screw?

 

A vacuum leak would generally cause the idle to be high, not low.

It sounds like the vehicle needs to be properly tuned using a tunable engine management solution such as hondata or neptune.

For more information on this subject check out the Phearable.net EFI beginner guide.

 

Start by setting your base idle. With a hot engine and all accessories on unplug the IACV and adjust the idle set screw until the rpm is where you want the idle to be. The service manual says ~750 but I like to set it to where I want it to idle 900ish. Then plug back in the IACV and youre done.

 

Yes. Hondata can fix your problem.

Idle speed is (very) sensitive to incorrect AF in the idle zone, Timing not set for best vacuum, fuel cut set at the wrong rpm breakpoint, idle speed vs ECT.

 

I cleaned the IACV, bled the coolant, took the throttle body off and cleaned it out real well. Still happening, so I think it definitely is just needing a tune, especially cause it had no problems before the aftermarket parts with the idle. I put a lightweight flywheel in there which could probably mess with the idle too. It's running rich too. I'll finish installing the turbo and take it to get a tune.

Thanks guys

 

way too many things can affect that problem, but any tuning platform can resolve decel issues. Assuming you don't have a mechanical problem, like your cam is off a tooth, bad compression, faulty dizzy, failing injectors, bad O2 sensor/exhaust leak.

 

Are you having the low idle only if the clutch is depressed? If the car is placed in neutral with the clutch disengaged does it idle normal?