Just installed idle controll valve on my 97 F355

I generally wear some clothes when resetting the computer on cars!

Kidding! You should turn off the battery supply for 5-10 minutes then reset and start car from cold, let idle for 10-15 minutes to reset ECU parameters if that's what you're alluding to. Not really necessary with a simple replacement of a part such as the idle control valve.

 

Clean the connectors. I use DeOxit. However, just clean them up. It s not rocket science, just need a good connection.

The grease you see is a di-electric grease used to keep moisture away form the connections and prevent corrosion. Not sure if that was original or not....

Once you re-energize the car, start it and let it idle for 10 minutes (or at least until the car heats up and the radiator fans kick in). The ECU needs to relearn the engines nuances.

 

Charles,
can I inquire on the reason for the ICV replacement?

 

+1

 

Just advice, not "professional" in any way or form. I have messed with that system a little in the past, and looked at all the various inputs it gets. There is also a throttle position sensor as well.

Cleaning your existing one would be a start. Next, I would clean the contacts on the plugs, as well as check the Motronic harness ground, which is on the right rear bank head. (near the spot where they are 3 or 4 various connector blocks meeting)

Wish I had known you were going in that direction, I have a used 'known good' one I could have sent you.

 

But there are two ICV's on a 355 right?

Howard

 

No...just one.

 

My bad

The 2.7 has 2 ICV's

Howard

 

One Idle Control Valve on the 5.2 Motronic. Two on the 2.7 Motronic.

 

I had a bad alternator last year and got a whole bunch of strange electrical problems. My temp gauge would read 220 even with the fans on and outside temps in the 50's and it would idle fast and then slow etc. When I changed the alternator and a bad battery form the alternator overcharging, all the electrical gremlins went away. The battery light never went on to indicate a bad alternator or battery.

 

Charles, I would hate for you to simply throw parts at this. I really think you need a proper diagnosis from a Ferrari specialist. I think it may end up being less expensive and frustrating that swapping parts. (warning/disclaimer, I am a "hack" and have no professional experience, only my own DIY work on my car, and reading the owners manual and workshop manual) I will tell you I have had a similar (but intermittent) low cold idle problem for several years. Dealer has been unable to fix the problem. I replaced the ICV, water temp sensor, and TPS. I also did the gold connector kit, and refreshed the Motronic ground point. No change. Dealer suspects there may be a bug in the Motronic, and I either need a new Motronic or a reflash. The car drives perfectly in all other respects. When I get the low cold idle, it can often be corrected by simply shutting down and restarting. Occasionally, I might have to shut down and restart two or three times, until I get a proper cold idle. If I let it simply stay at this lower cold idle of around 750 rpm or so...it will eventually creep up to around 1000 or 1100 rpm after 40 to 50 seconds. Normal cold idle is around 1400 rpm.
Again, intermittent, I might not see this for several cold starts, then it happens. NEVER happens if the engine is even slightly warm...only when dead cold.

But, if you wish to continue down this route, there are two things to consider:

1) The Motronic determines the engine is "cold" based on the coolant temp sensor located near the oil filter mount. (check the parts diagram for exact location) If that had failed, it might give the Motronic the indication the engine is always warm, when in fact it is cold, thus the low idle upon start. BUT, I would suspect a bad sensor would trip the "check engine" light...but am uncertain about that. This sensor is seperate from the sensor that works the water temp guage on the dash.

2) The throttle position sensor tells the Motronic....well...the throttle position...whether at idle, off idle or wide open throttle.. Not sure how to check what without and SD1 or SD2. But they are not expensive...but reading the WSM, there is some skill to adjusting it properly.

Do you have an OBDII scanner? It would be worth it to buy an inexpensive one that reads the various sensor outputs. They would quickly tell you the readings on the coolant sensor, and that will tell you if it is reading correctly or not. Plug it in, and start the car when cold, and see what the temp reading is...and see if it raises as the engine warms up.

If you own a laptop, go to Ebay and search for "ELM 327" and that will bring up a connecting cable for your laptop to connect to the OBDII port, along with some "freeware" to go along with it. Should cost less than $11 from Hong Kong vendors.

I have one similar to this: http://www.ebay.com/itm/V1-5-ELM327-OBD2-OBDII-CAN-BUS-Auto-Diagnostic-USB-Interface-Code-Scanner-Reader-/180819846569?pt=LH_DefaultDomain_0&hash=item2a19b3e5a9

Once you have the cord, you can use the software it comes with, or use any number of freeware options online, or buy one if you like...but the software it comes with works fine.