I have the "Service Engine Soon" indicator lit up in my 1996 SL2 (124,000 km). Being a good conscientious owner I took it to the dealer to remedy the situation.
The young man labored over his computer and the service writer quizzed me about when I'd last fuelled up. (I'd already checked the fuel tank cap for tightness.) They had no definite diagnosis except that it was code P0440, Evap system.
So they cleared the code and sent me on my way, saying if it re-appeared to return. I didn't even make it out of the auto park before "Service Engine Soon" was back, so I returned.
Well, they'd have to do a longer diagnostic a "smoke test." 99.9 percent of the time it was a loose gas tank cap, they said.
I haven't had time to leave the car again, but I pictured a smoke test to have something to do with exhaust gases. However, I now think they may use smoke to test for air leaks in the evaporation system.
Anyhow, has anyone:
- Had that error code.
- Had a smoke test.
Thanks for any and all replies.