Hi All - having not used my 575 for about 3 weeks I’ve started her up and it’s like it only has about about 20% of the power it should. I’ve actually experienced this before but usually a simple switch off and wait a minute then restart solves the problem. This time no luck though, she literally just has a serious lack of power but apart from that it actually runs well. Goes through all the gears fine and no warning lights. I thought that maybe it's a fuelling issue but I need some advice if anyone has any ideas. Thanks as always.
Have you checked for "pedal limp" mode with an OBDII reader? Pedal limp is 20% of accelerator. There should be some trouble codes as well. This mode is typically caused by problems with the drive-by-wire circuit. The two potential problematic areas are the throttle bodies and the accelerator potentiometer. The AP is easy to check with a quality scanner like the Autel AP200. Show live data for the two AP pots, then show them as a combined graph. They should line up perfectly. If they don't, $400 part that can be replaced in 15 minutes. If it's not the AP, then it's the throttle bodies. A bit more expensive to replace or rebuild than the AP but still, two of the easiest components to reach and replace. I wrote a long and boring article about my battle with pedal limp. https://www.ferrari360.org/2020/07/bosch-throttle-body-replacement.html
Another thing it could be is one bank's Motronic ECU not working and it's running on six cylinders. It will run smoothly on one bank but will have very little power. Easy check is to hold you hand over each tailpipe and see if one side has no hot gases coming out.
The Maserati 3200 has a lot of problems with the TB and pedal pots as well. It is a Magneti Marelli system used by Volvo and Lamborghini for the gallardo as well. There the problem is the contact on the carbon strip inside, which wears out on both sides of the system. Solutions have been developed by replacing the carbon brush to magnetic (contactless) systems. I do not know if it would help, but in the UK there is a guy who has developed the contactless pedalpot for the 3200. And as it simply is a system that provides a range of volts when the pedal is pressed, maybe this could work on the 575 as well.
It was the accelerator potentiometer! I chanced it and bought one for £200. Switched the battery off and put the new one in, looks like 20 minutes but a very frustrating and fiddly job. The car is back to normal now. Thanks all.
Yes I know it is a fiddly job, had to do that on my old 3200 several times, working under the dash... By the way, on the 3200 there were 2 carbon tracks inside the pot, I guess that is the same with this one. The system monitors the two volts supplied by the tracks (2 seperate wires, yellow and white), and when one track breaks, its more or less goes into limp. Some 3200 owners have connected the two wires outside of the pot to always have an average voltage that keeps the car driveable in case one track breaks/ wears out. You might consider that and modify the broken one that way as an improved limp home spare.
