Hi all - Happy New Year,

Got a hard start problem which kind of fluctuates day to day.

My 1987 190E, 2.6 is a hard start - hot or cold. Worse when cold. When the car warms up there is a lack of power and sluggishness.

The symptoms are constant when I have the above problem.

The O2 light comes on and stays lit. Depending on the day, it may go off as I drive it may not. Stays on more often than not. As the o2 light stays on the car is sluggish and there is a lack of power as I drive.

When and if the o2 light goes off as I drive, the power improves and the sluggishness goes away. Running like it was made to. This does not happen often.

I have replaced the o2 sensor and the exhaust from the manifold back.

Worked well for a while then went back to the o2 light coming on and the same symptons.

I then changed the Ignition Control Unit when a nipple that leads to a vacuum line broke.

Once again replaced that and the car started up and ran fine. This lasted a day or two and the o2 light comes on and once again the same symptons.

I then checked and cleaned the idle control valve and a tube that leads to the bottom of the engine bay, that was craacked and brittle. Valve was clean and replaced.

After the above, the car sat over night and started right up in the morning, no o2 light - no issues. After my 1/2 hour drive to work no issues. When I went to start the car after 8 hours the o2 light came on and the problems persisted.

The OPV relay has been replaced. No changes.

So anyway, here I sit and type. The one constant I have is that when the car runs like crap the o2 light is on.
Hard start when cold, but as the car warms up it may run better but it is still sluggish and has a lack of power. But if the o2 light goes out for whatever reason the car improves until it comes back on.

Thanks in advance, Dwayne