So i just picked up an 84 325e with 290K on it. The deal was too good, couldn't pass it up. The car runs good, but i took it in to try to get the Ca. smog nazis to pass it, and no-go. failed on high hydrocarbons and timing. Timing!?!? Acording to the tech the advance has to be 16 deg. +/- 3. mine is runing at 11.5. So i took it home and checked, sure enough, right around 12 deg. So i did a tune up on it, and threw in a new O2 sensor for the hydrocarbons. I double checked the timing, right where it was. Iim going to try to find an inspection station that wont fail me over 1 degree of timing, but my question is; isn't the timing completely controled by the ECU in this car? Is there a way to advance the base timing to make up that degree? Is there some other sensor that could be retarding the spark? Any ideas would be apreciated. Thanks in advance.
'84 325e wont pass emissions
- Thread starter mzm22
- Start date
Yes, the timing is completely controlled by the ECU. The only way to advance the base timing would be to advance the camshaft phasing when installing a new timing belt - but this won't just advance the ignition timing, it'll advance the valve timing as well. Otherwise there is no way to just advance the ignition timing that I am aware of. Maybe the last time the timing belt was replaced, the new belt was installed with the camshaft a tooth improperly retarded??