TurboGoKart

Just swapped a D16Y7 into a car that previously had a D16Y8 in it. I used the Y8 intake, but the Y7 throttle body b/c of needing the 3 wire IACV. All wiring was completed, no CEL's.

When you first start up the car, it idles perfect. If you drive it for a few mins, the rpm's will eventually start surging. If I use my hand and rev it up via the gas pedal and pull back to close the butterfly plate, it returns to a normal idle. I used sandpaper already to clean the inside of the TB where the plate closes, and that did not help. Any ideas?

I would think a vacuum leak, but it doesn't do it all the time. Just random. Could it be because I still have the Y8 IACV on the manifold? I'm using the 3-wire Y7 IACV on the throttle body and the Y8 IACV isn't hooked up though. Do I need to take the Y8 IACV off and block that off?

TurboGoKart

Since I left the Y8 IACV on there, I have the coolant line coming into the Y7 IACV, then to the Y8 IACV, then back to where it goes. Basically I'm running coolant thru both, but that shouldnt have anything to do with the idle right?

Also, I put the Y8 spring and throttle plate (gold plate thing) on the Y7 throttle body.

Stine

I had the exact same problem on mine when the throttle stop when the throttle is closed was set to far out so the butterfly in the TB was open to far and the IACV was shitting itself. Adjust the screw on the TB out just until the butterfly doenst stick in the bore when the throttle is closed all the way. I had to **** around with it for a while to get it setup perfect. Then if your idle drops and comes back up after you adjust this you now need to adjust the air bypass screw on the throttle body until its setup to how you like it.

Stine

This is the reason the throttle stop needs to be adjusted in the first place, i swapped rotors too.

TurboGoKart

Lol. I'll have to mess with it. Right now IIRC, the throttle stop screw isnt even touching the throttle plate. I was thinking it needed to close all the way, so I moved it out of the way.

If I understand you correctly, you're saying I need to actually open the throttle plate just a touch via the throttle stop screw? Then adjust the idle via the air bypass screw?

TurboGoKart

Bump for last question^^

teamworxek9

iTrader: (5)

why do you have the coolant lines running through the iacv not hooked up to the ecu? you are just using it as a block off right.

TurboGoKart

Yeah. The IACV not being used was already hooked up to the water pipe or wherever it goes under the manifold. It was easier to run it thru there than find another line long enough to run from the IACV being used to the water pipe.

TurboGoKart

Bump. Is it really necessary to take the old Y8 IACV off and block it off?

TurboGoKart

Also, still getting the random idle surge thing. I'm almost thinking about switching back to the complete Y8 intake/throttlebody and just using the Y8 ECU. Obviously I'll get a CEL for VTEC, but shoot, if it takes care of this freakin idle surge I'm almost game.