I was driving my F40 near my house going at 3k revs about 40mph. Nothing hard. Suddenly, my right bank (1-4) slowdown light started to flash, then it stayed on. Oh oh. The right bank then appears to have shut down as I was pulling off the road. The slowdown light turned back off, the bank seemed to come back and a cloud of blue smoke billowed out the exhaust as the bank fired up and the smell of something really hot permeated the cabin. The slowdown light was back on solid. Something was indeed cooking back there. I shut the engine off and pushed the car the rest of the way home as I was a hundred feet from home at that time. Mind you, all the above happened in rapid succession. Sensory inputs galore. No bad sounds of something crunching, just lights, 1-4 bank going off/on, and the car getting ready to cook marshmallows. The one bad thing about my seating position is that I cant see the slowdown lights as they are directly behind the steering wheel. Thus, I do not know how long the slowdown light was flashing before I noticed it. :-( I did see the transition from flashing to solid which means SHUT IT DOWN IMMEDIATELY. Fast forward to the next day. I started the car and monitored the exhaust temp with an infrared unit. After warming up, the right bank exhaust was cooler than the left by about 80 degrees. Both turbos were the same temp so it seems like all cylinders were firing. Car was rough when cold then settled out when warm. Any idea what happened? Did my brand new right side Hyperflow die during the turmoil? Seems like if a cat died, it would run a cooler exit exhaust, right? Did something happen to the right bank to cause lots of unburned gas to be fed to the cat which caused the cat to run hot, trigger all the slowdown lights, and then die? Or, did the cat just die on its own? The latter seems unlikely. Ive got my major coming up in a few weeks so Im just going to button up the car and wait until its time to send it over. Thoughts? Laughter? Tim
That same IR unit can be used to see if the cat died. If it is dead, the cat will be approximately the same temp as the exhaust pipes. If it is alive, it will be hotter.
The cats were actually cool(er), like they were somewhat insulated. Maybe I needed to let them run some more. The fans were already kicking on/off so the water temp was up there. That's why I had to measure the exhaust pipes (and turbos) and look at the difference between all 4 readings. - Tim
Sounds like a failing/failed Cat ECU. Here is how the 348 Brotherhood checks this problem. 1) Swap the cat ecu's from side to side. If the slow down light jumps sides you have found the problematic cat ecu. If the light does not jump sides- 2) Swap the thermocouples from side to side. Same deal. If the light jumps side you have found the bad thermocouple. If the light stays on the same side still, then you have a genuine over heating problem of the cat and will need to further investigate. Almost all of the time it turns out to be a bad cat ecu. The reason is because the back of the cat ecu gets cracked and allows moisture to get inside the housing. Water and electronics don't mix. As for the bank shutting down. With my 348 I can unplug the cat ecu and the bank will run just fine. Matter of fact I have have my stupid cat ecu's completely disconnected for years and the engine runs. Again this is on my 348, and being that yours is an F40 AND has turbos that sort of changes the situation. Anyway hope that helps? Oh yeah and one more thing. One of the guys, Marco, has a Mondial T, and he made himself a pair of metal chore spiral cats. One of the metal chores did fail on him and it did cause problems. Heres the link to that thread http://ferrarichat.com/forum/showthread.php?t=227951 So it wouldn't be far fetched to think that you did have a cat fail. I dunno how hard it is to disconnect F40 cats, but on my 348 I could have it off in around 30 minutes. So you may want to check the cats first, and then try swapping things from side to side , if the cats check out okay.
Seems like I dont need to swap the ECUs or thermocouples because the heat was real, as I mentioned above. If anything, theyre confirmed working because they saved me from cooking the back half of the car! I confirmed the right cat is toast. I just took the car back out and ran it up to temp this time, including turbo usage. Car ran great. I came back and measured the following (all max temps from the infrared device up close): Left turbo: 682, Right turbo: 733 Left cat: 496, Right cat: 390 Left exhaust tip: 620 (!), Right exhaust tip: 418 The turbo temp differences are probably because I couldnt measure the exact same angle on each. Close enough, however. I about choked when I saw the left exhaust tip at 620!!!!! Those Tubis sure get hot. I measured the left exhaust area a few times. Most readings were 570 or so. The 620 was seen only once as I was moving the gun around looking for the hottest area. Anyway, the right cat is cooked. The only question was it because of the engine dumping gas into it, or did it just have a defect and blow. The cats literally have about 1 hour on them total. Problem is, I bought them 2 years ago and used them, um, for 2 short times. :-| Tim
Tim, please keep us informed after your mechanic has a look. And, please post some photos of the dead cat after it has been removed. Just glad to hear that you F40 is running well after that short nightmare!
I am not an expert and not giving any advise. However, assuming your cat is upstream from your turbo; if the cat broke apart on the inside and sent debris downstream, could it have damaged your turbo's fins? Maybe it's nice wise to run the car? Just a thought.
Yea, that point wasn't lost on me when I was taking the readings. :-| I didn't know if the thermo probe was getting (over) hot from the cat a few inches away downstream or actually from the exhaust coming from the turbo/engine. If from the engine, seems like an injector would have to be stuck open or something to dump gas into the exhaust and ignite. But, wouldn't that fry the turbo at the same time? Tim Image Unavailable, Please Login Image Unavailable, Please Login
