575, COLD start up issue.

Check the cold air valve.

 

Sorry, the 575 did away with it.

Attached are both the 550 and 575 parts diagrams.
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I have a similar issue, but it is not consistent.

Most of the time, the engine will idle roughly for 1 - 2 seconds, then speed-up and idle correctly. Other times I have to wait for 5-10 seconds before the engine idles correctly. Tapping the throttle helps immediately. I too have disconnected the battery and gone through the re-start procedure with no apparent improvement.

 

Bill, I was baffled by your problem because I thought your 575 had idle air control valves like our 550's do, and they would normally control the fast idle warmup RPM, not the main TB's. However, I can't find any mention of them in the parts diagram or the WSM for the 575.

So it appears your idle speed is controlled directly by the main throttle bodies, so IMO, it sounds like one or the other may be sticking just a tad, and tapping the throttle is "unsticking" it. I'd be tempted, therefore, to give the throttle body butterfly shafts a shot or two of carb cleaner where they come out of the casting, and see if that might help.

It might also be worthwhile to pull the MAF's out and give them a cleaning with some dedicated MAF cleaner (I think CRC sells it?).

Perhaps Brian or the other pros would have another idea.

 

Bill- Mine has done the same thing intermittently and is on one of its bad streaks now. I think it is injector leak-down, but am not sure. A double start always works. techron fixed it once on mine, but not this time. Will keep fiddling with it. 360 has the same problem.

 

Bill,

From personal and professional experience, Techron is the best valve / fuel injector cleaner. I use it in all my cars because of the cold climate in Calgary (lots of idling to warm up engines)

 

Bill I still use the old school Gumout, because I'm old school too

 

Bill- I start her and if she does not immediately run up to 1400 rpm on a cold start, and stumbles around 400 rpm, I shut her down, wait for the Check OK, and restart. Works every time, but double load on the battery and starter.

The throttle body trick is certainly worth trying. If it was the MAF meter, it would not work perfectly on the second start.

 

Bill
I hope you are making progress on your issue.

I am not an engineer but do have a question for those that are. I am surprised the car does not have an IAC valve. I am also surprised if Ferrari is trying to control idle speed with the throttle plate. I'd have thought it was too much of a blunt instrument. So, for the engineers and pros out there, how is the idle speed controlled on a 575?

Philip

 

Philip- Idle speed is not the issue, that is steady as a rock at ~800 rpm when warm. Cold start to high idle is the problem. Once she hits 1400 rpm, a steady letdown to 800 rpm works perfectly. Getting her to 1400 rpm is the problem.

 

I have the same problem with my 456. When cold it will not idle at high speed unless I blip the throttle. Then it goes to normal, high idle speed. I thought it might be the injectors leaking down, so I sent all of those off to be cleaned and calibrated while the car was in for its belt change. The cleaned injectors made no difference. I thought perhaps it was the IAC valves, so I took them off to clean, but they were perfectly clean. I electrically tested them on the bench, and they worked fine.

I think I have traced it down to the throttle position sensor. If I remove the connector from the TP sensor while it is in its slow, "fast" idle, and reconnect it, the fast idle is restored. It's not a matter of fretting on the connector, replacing it once should cure that. Plus, I cleaned the contacts with contact cleaner and used stabilant on them to no avail. What does solve it is disconnecting and reconnecting the TP sensor while the engine is running.

This brings up the question, can the TP sensor itself be replaced or is it an integral part of the throttle body, meaning the entire throttle body must be replaced ($$$)? Any advice?

 

Mark- The 575M Motronic 7.1.1 and 456M Motronic 5.2 differ so vastly in cold start and idle mechanization I am not sure there are many lessons to be learned from one to the other. 550 owners have had their injectors flowed, cleaned, and resealed when they had no cold start problems at all. They then found out they had injectors leaking and flowing poorly, but no obvious symptoms.

Motronic 7.1.1 (575, F430, early 612, early 599) cold start seems to be more sensitive to injector operation than Motronic 5.2 (late F355, late 456, 456M, 550).

 

YES, the TPS can be replaced separately, and they are very cheap - I Alfa/etc. carry the same one.

Part #: Bosch: 0 280 122 001 ALFA ROMEO: 60549359, ALFA ROMEO: 7637025 ALFA ROMEO: 9946862, CITROËN: 1628 L1 CITROËN: 72 408 124

Can find them on eBay Germany for around 30/40 Euros.
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Thanks! I found the part on ebay (new) for $16 including shipping! I'll find out next week if this cures my start issue.

 

Good luck and remember to post results so it will help the next one with your same problem.

 

Terry,

Apples and oranges obviously, but sometimes I experience the very same symptoms you described with my 3.2 Mondial. Instead of turning the key off and reigniting the engine, I give it a bit of throttle and problem solved. Revs go up and stay up, then come down steadily to normal warm idle. Don't know if this practice is advisable on 575s, nor if it solves the problem, but has anyone tried it? How did the engine respond?

Kind regards,

Nuno.

 

According to the online retailers - Ricambi for example, the correct P/N for the 456 TPS is 0 280 122 004 - that's the part number on mine. I don't know the difference between the -004 and -001, but there sure is a price difference.

 

Nuno- Like the double start, that is just a Band-Aid, and I always want mine to work like she is supposed to. No throttle added on my starts. I used the double start until the Techron overdose kicked in. Injectors rectified cured it completely in my case.

 

I am experiencing the same issue of very rough idle, sometimes snuffing out on cold starts. I am dropping the 575M in for service to look into the problem today. They have already suggested that it may be any one of the reasons suggested in this thread. It was good to be able to confirm they are on the right track through this forum. I will let you all know the outcome.

 

Jay- Cleaning the injectors is good maintenance practice for a 575M, at any rate. The rubber seals tend to deteriorate from contact with alcohol and the injectors start leaking. Here are the before and after results from mine. The injectors were resealed with Viton seals that alcohol does not bother.
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Sorry for delay in update. I decided to try cleaning the injectors and was driving around the city to use up the tank of fuel and things took a turn for the worse . The engine block light came on along with beeping, a few times and as I tried to make it to my dealer who luckily was in that area, the engine would cut out all together when I took my foot off the accelerator. I only just managed to get to the dealership. They put their diagnostic equipment on and found that the the clutch plate sensor was faulty and not indicating when the clutch was disengaged. I waited 4 weeks for them to get a replacement part from Italy(I am in Australia). Yep you guessed it, wrong one.

Not real happy, have to wait another two weeks (at least) for another part to arrive and still do not know if this will fix the original problem? Miss my car.