Hi, I recently acquired a 1990 Ferrari 348 TS with 4k miles, beautiful Concourse conditions I was diving it when suddenly the car engine started working on a "Slow drive Mode Warning". After driving it on that mode for 1 mile on a stop light, the engine itself shut off. When I turned the ignition back on, there were two dffirent warning ligths: "Check engine 1/4" and "Check engine 5/8 " Could any one help me to find out what those warning lights mean ?? After that happening the car runs well and normal, but every time you turn the ignition on, those Warning Lights Show up. Thanks in advance for your help. Andres Martinez Key Biscayne Florida e-mail: [email protected]
Those idiot lights are on every time you turn the key on, before the engine starts. They are part of the "check" procedure, along with a few other lights. Reda the Owners Manual. If they're on while driving, you have trouble codes in memory. There are two "Check Engine Lights", (one for each bank of 4 cylinders). Your engine is set up like 2 four cylinder engines that share a crankshaft. The "Slow Down", is telling you that your catalytic converter(s) are overheating due to a misfire or excessive fuel situation. Ultimately you could end up with a red hot cat that could start a fire. It's always a good idea to take the warning seriously, but malfunctions of the system are very common. If you get "slow down" almost immediately after starting out, it's unlikely that anything is overheating yet. If you've been driving fast for a while. It might indicate a problem.
Not sure if this will help any, but back in the 90's (on my 355) I had the "slow down" warning light start coming on while just cruising in traffic at 25-35 MPH. The cats themselves were fine and not over heated, but the "slow down" light would randomly come on and off for no apparent reason. It turned out the cat ECU's (which monitor the individual cat temps) had started to fail and were giving erroneous data to the main computer on the car. There is a right and left side ECU (one for each bank) and I ultimately had to replace both. The issue back then was that the housing/sealant around the cat ECU's module would start to separate and allow water/moisture to reach the circuit board and cause issues. If you spray down the engine area to clean it and/or drive a lot in wet weather, you can end up with water in those modules back there. Replacing both cat ECU's solved the issue on my 355. I'm not sure if there is a similar issues regarding the 348, but perhaps. Ray
355 actually has 3 of those silly little failure devices . 348 only has 2. First step..swap the temp probes from one side to the other..if the problem follows. You just saved yourself 1000 bucks. If it Doesn't change swap the ecu..if it follows. Congrats! You get to pay $1000!
am i not right thinking the cat ecu can be disconnected ? But of course then no protection for cats...
This is one of those situations where the "monitoring system" is more problematic than the perceived problem. Solution: remove monitor....
These lights always come on when you turn on the ignition (before start). Which bank? As you were driving, the cat overheat warning may be real. Don't ignore it. As suggested, swap cat ECUs and thermocouples if the problem is present on one bank only. If you have an infra red temperature gun, compare the left/right temperatures.
