993 ICV Install

earossi · 02-04-2014, 03:53 PM

Did a search and could not answer my question, but when installing the Idle Control Valve, which direction should the arrow point that is cast into the valve? Should it face the front or rear of the car? Apologize for my laziness, but I'm just tired!

cmonref · 02-04-2014, 04:03 PM

If it is like the ICV on the 3.2L, the arrow shows the direction of airflow thru the valve.

earossi · 02-04-2014, 04:27 PM

Quote:

Originally Posted by Brian K. Haggard

If it is like the ICV on the 3.2L, the arrow shows the direction of airflow thru the valve.

True, I believe the arrow denotes air flow through the ICV. But, the valve can be installed in a way to reverse that flow. On the 993, the plumbing at the ICV makes it a bit difficult to determine which way the air flows. Which was the reason for my question. Installed on the car, should the arrow point to the front or rear of the car?

jhg41977 · jhg41977's Garage

Which way is the plug facing? Chances are the plug wires have settled in the correct direction so the icv can only go one way right?

earossi · 02-08-2014, 04:07 AM

Quote:

Originally Posted by jhg41977

Which way is the plug facing? Chances are the plug wires have settled in the correct direction so the icv can only go one way right?

That's a good point. However, when I rebuilt the motor I replaced the 17 year old engine wiring harness with a new one. So, there was no "set" in the new harness.

I'm trying to solve an idle issue that I did not have prior to the rebuild. The motor starts up fine and idles right down to about 800 rpm. But, as soon as you place a load on the motor and then declutch the engine, rpms drop right down to stalling. I can feather the throttle and inch the engine down to idle and the ICV will then catch it. I did flush the ICV thoroughly with carb cleaner before mounting it on the new engine.

I do have a new ICV to mount on the engine, but began thinking about the possibility of the ICV being hooked up in reverse fashion. That prompted my original question on this posting.

jhg41977 · jhg41977's Garage

I'm away from home right now but I will be back late tonight. I am fairly certain I have pictures from disassembly that would show that. I'll post one for you .

jhg41977 · jhg41977's Garage

Or you can try this one from pcar workshop .
993 - ISV Cleaning - pcarworkshop

earossi · 02-08-2014, 06:15 AM

Perfect! Exactly what I was looking for. Thanks so much. I have not looked at the PCA Workshop website for quite a while.

jhg41977 · jhg41977's Garage

You're welcome, not sure why I didn't think of it the first time I saw your post.

Bill Verburg · Bill Verburg's Garage

The ICV is a push/pull device that receives it's input instructions from the DME

besides mechanical obstruction of the butterfly the electric contacts can become worn at the central position.

a new ICV solves the problem but you can also try to re-position the neutral spot, The 3 screws connecting the outer case and the inner works are sealed, Dremel the seal, loosen the screws and rotate the outer and inner parts slightly, this moves the neutral contact spot to a less worn area.