| Author | Message | ||
| Rob Schermerhorn (Rexrcr)
Member Username: Rexrcr Post Number: 736 Registered: 11-2002 |
This is corect, slow down light is triggered (ostensibly) by high catalytic converter temperature (I don't remember the spec, the threshold's been posted). So, if no catalyst, and the thermocouple probe is still installed in the exhaust, it's either running very hot (doubtful) or the thermocouple ECU is malfunctioning, or wiring issue. Agreed, more than likely you're not running too hot and it's electrical. Disconnect if you wish. IMO, keep the catalysts installed and help keep the environment clean, they don't cost much, if any, power (maybe 2-3 hp).  | ||
| Rob Lay (Rob328gts)
Board Administrator Username: Rob328gts Post Number: 5583 Registered: 12-2000 |
Challenge cars do this too. Exhaust system related as that's the only Challenge mods. | ||
| allan fiedler (Allanlambo)
Member Username: Allanlambo Post Number: 679 Registered: 6-2002 |
Took the car out tonight and it ran fine, no slow down lights. Thanks for your help! | ||
| P. Thomas (Ferrari_fanatic)
Member Username: Ferrari_fanatic Post Number: 454 Registered: 4-2003 |
The later 355 had (2) O2 sensors. One "up stream" and on "down stream". It measured the difference and if the variance was nominal it thought that the cat was not cleaning up the emissions. That would trigger a check engine light. He is talking about the slow down light which is controlled by the thermocoupler. Some have found the ECU faulty and that trigerred a bogus slow down light. Regardless, if your cats are off there should be less heat generated so it definetly should not set off a slow down light. Check engine light if on a later 355, yes. | ||
| Mark Moon (Enzomoon)
Junior Member Username: Enzomoon Post Number: 164 Registered: 4-2002 |
Allan: Same thing happened with my 355 after Test pipes were put on. This is common, having something to do with the O2 sensors. To my knowledge it is completely benign. I had my mechanic simply disconnect the slow down light. It won't affect performance whatsoever. Hope this helps Mark | ||
| allan fiedler (Allanlambo)
Member Username: Allanlambo Post Number: 678 Registered: 6-2002 |
car has no cats. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 873 Registered: 4-2002 |
Cat got too hot. | ||
| allan fiedler (Allanlambo)
Member Username: Allanlambo Post Number: 677 Registered: 6-2002 |
While driving my 355 today, the "slow down" light came on and was flickering on and off. Car seemed to be running fine, good oil presure, temp ok etc. My car has custom headers, cat bypass and exhaust and this has never happened before. Then it just stopped. Any ideas? |