I want to know if my car runs slower if the cel is on. It's throwing a air/fuel monitoring CEL code cause i aint gotta catalytic. so does the CEL put the ecu in low performance safe mode?

 

Not alway's. When it's in "safe mode" you'll notice it running real rich and will not rev past about 4000 RPM. Alot of times if your just getting an o2 sensor code or the heater code it will not set it into limp mode, but just throw a CEL.

 

ok my car is a 99' civic si boosted. so the only thing safe mode does is restrict the revs to 4000 rpm?
My car can bounce off the rev limiter even with a CEL which
I installed the CEL bulb this afternoon and now it's not sending a CEL and I drove it for about 20 minutes, no CEL.
Let's see what happens. so safe mode just restricts the revs to 4k rpm? thanks in advance.

 

In a serious case, when theres a serious problem like your eeprom is installed incorrectly, or if a wire gets crossed to the ecu for whatever reason, yes the ecu will restrict rev's over about 3-4k rpm. It's a "safe mode" just like you said. It's there as a backup for the driver to get the car someplace for repairs but, not every CEL code will set this "safe mode" off.

 

thanks tranceminister, i miss that fat guy bopping his head to the music in your avitar.

 

Hey, hey now... What if that fat guy was me? (don't worry it's not) Anyway, glad to help, hopefully you've solved the CEL probem and it won't come back. And hopefully newbie Forces will be up and running again and my fat guy doing the head bop will come back