Please help with Check Engine Light
 

I have a 1990 300ce, for the last 2 years the code comes up 17.
O2 related, ground mod in place, new O2 installed, will check the new O2 this week.

My "Check Engine" light comes on only after I "Kick it in the butt", hit 7000 rpm in 1st, slam into 2nd, go to third, and slow......cruse to wherever, stop, restart, "Bam Red Light".........code 17.

We have cleared the computer, and after a few months of "No Light" I pounded the throttle again........Pa Pow code 17!

Never a driveabialty problem......

????

Thank's,

Tim

Have had that problem on several 1990 & 91 cars. The O2 heater must work so that the O2 sensor gets hot enough to go into "closed loop". The heater must receive battery voltage from the MAS relay. Many times the O2 sensor heater only gets 6-7 volts & LAMDA never works properly.

M.B.DOC

Thank's for the info, way over my head, but my Tech said ah yes! I am going to take it in tomorrow and let them check it out.

If we get a low voltage reading would you sugest replacing the MAS?

Thanks again,