Intake Air Sensor Location

Trying to diagnose an increasingly severe pinging problem at 2,000 - 2700 rpm on 91 octane fuel.

I am looking for the intake air sensor for my 1995 E34 (April 1994 production).

The Bentley Manual shows it right below the nipple for the brake booster, but on my car there is nothing, not even a dimple at that spot. The factory Intake manifold diagram seems to indicate it is on the bottom of the manifold, but I cannot seem to find it.

I am trying this as changing plugs, new Oxy sensor, inspection of cylinder inside for hot spots, review of 2 knock sensors reveals nothing out of line. 145K miles, passes smog cleanly, uses no oil.

TIA.

Could be a bad knock sensor not adjusting the timing correctly. See if you can find anything on this in the Bentley manual. Could be a build up of carbon on top of the pistons. Some say a Sea Foam treatment will help this. Roberto will likely give you his advice on de-carbonizing the pistons with water.

Good luck. Sorry to be do brief.

Steve

Thanks. I had a shop try to find the cause last summer - they changed out the Oxygen sensor (overdue), tried new plugs, looked into the cylinders with a boroscope and found them clean, tested the knock sensors and found them both working. They finally gave up.

I was hoping to test the air intake sensor and find it misreading, as the pinging gets worse with increases in outside temperature. Fortunately it goes away on the freeway when the car goes into high gear.