problem since iac and fitv cleaning

[rkJDM]

The probems i am having are slow deceleration with my foot off the throttle whether cold or warm engine temp. I take my foot all the way off the trottle and the engine struggles to decelerate, and when i maintain rpm it feels like the engine is creeping the rpm up and down, but if i watch my tach theres very little to no movement while i can feel it happening. The last problem is when i start it cold, the rpm goes up to 1750 and stays there no matter what i do. But when it starts to warm up it slows. Then when it gets to norm op temp it slows to 550-900 rpm. When it gets to norm op temp and reaches 550-900 rpm, the idle pulsates from rough to smooth. I have a narrow band fuel/air ratio gauge and it goes down to extremly lean at rough idle pulse. And up to extremly rich when smooth idle pulse. Im not sure of the gauge accuarcy though. These problems all occured 24 hours after i cleaned my iac and fitv. I have a 94 civic si d16z7 with t3/t4 turbo kit, 8 psi wastegated, installed with the missing link and aem fuel press. Reg. Installed, but no tuned ecu. Any help is appreciated. Thanks

 

[RonJ]

Any CEL codes?

The probems i am having are slow deceleration with my foot off the throttle whether cold or warm engine temp. I take my foot all the way off the trottle and the engine struggles to decelerate, and when i maintain rpm it feels like the engine is creeping the rpm up and down, but if i watch my tach theres very little to no movement while i can feel it happening.

Clean the throttle body and make sure the throttle cable is adjusted to have as much as 1/2" of slack.

The last problem is when i start it cold, the rpm goes up to 1750 and stays there no matter what i do. But when it starts to warm up it slows.

This is normal on a cool or cold morning.

Then when it gets to norm op temp it slows to 550-900 rpm. When it gets to norm op temp and reaches 550-900 rpm, the idle pulsates from rough to smooth.

Warm up engine. Remove the air intake system. Use your finger to cover the hole inside the throttle body leading to the FITV or IACV. Does covering one of those two holes eliminate the hunting idle?

These problems all occured 24 hours after i cleaned my iac and fitv.

Check for any disconnected vacuum hoses. Did you forget to re-install the rubber gaskets on the FITV and IACV?

I have a narrow band fuel/air ratio gauge and it goes down to extremly lean at rough idle pulse. And up to extremly rich when smooth idle pulse. Im not sure of the gauge accuarcy though.

I have a 94 civic si d16z7 with t3/t4 turbo kit, 8 psi wastegated, installed with the missing link and aem fuel press. Reg. Installed, but no tuned ecu.

Don't cut corners with turbo. You need a wide band sensor and gauge and a tuned ECU. If you don't do it right, your engine will soon be toast.

 

[rkJDM]

Well i am totally shocked, i went for a drive after work today to warm up my car and all the problems have stopped! I have no idea why but it idles fine @ 750 rpm and the decelerating has returned to normal. No more weird idle or rough idle at all. Thnx for your help. Could it be that it just had to relearn the idle?

 

[jdmd.hatch]

What happened with that you had a vacuum leak by the rubber gasket of the iac. When the engine warmed up it "melted" to make a seal. Also get tuned and get rid of the narrow band Christmas tree, get a wideband.