all these problems lately <:C where to start?

[[1990]525]

1990 525 m20b25 Today my oil pressure light (red) has been coming on @ idle, revs dropping below 500 then throwoing up to ~700 back and forth while I idle. The light flickers on and off during this period (not steady). Dipstick says oil level is normal. I had drained about a litre of oil 2 weeks ago because it was showing VERY high on the dipstick.

Is it possible my dipstick lies to me? Should I run seafoam through it and do another oil change soon going back to Mobil 1?

It also has been losing power for seconds at a time during normal driving.

Where should I start?

Perhaps take into consideration these problems:
http://www.bimmernut.com/forum/showthread.php?43165-lol-que-sludge
http://www.bimmernut.com/forum/showthread.php?43134-e34-bleeding-coolant-troubles

[Ross]

Oil pressure and oil level are unrelated other than no oil= no oil pressure.
Idling so low should be expected to set the low pressure light flickering. The low pressure is a result of the low idle not the other way around.
Unless your crankcase was overfilled you need to examine what is going INTO the oil; fuel from leaking injectors or coolant, coolant will turn the oil milky, fuel will simply dilute it compounding any low pressure condition.
Your surging idle is likely a vacuum leak or idle control valve fault.
Seafoam will do nothing for any of this.

[[1990]525]

Oil pressure and oil level are unrelated other than no oil= no oil pressure.
Idling so low should be expected to set the low pressure light flickering. The low pressure is a result of the low idle not the other way around.
Unless your crankcase was overfilled you need to examine what is going INTO the oil; fuel from leaking injectors or coolant, coolant will turn the oil milky, fuel will simply dilute it compounding any low pressure condition.
Your surging idle is likely a vacuum leak or idle control valve fault.
Seafoam will do nothing for any of this.
I recently cleaned the ICV and plugged a vacuum leak related to the brake booster (check valve). Might be more to it. If I'm losing as much coolant as that thread says, it's likely not going into the oil, right? How can I trouble shoot the injectors? What beside overfilling / coolant/fuel leaking into oil could cause the dipstick to read high?

[[1990]525]

Can you give some brainstorming on this hypothesis?: it was raining that day and the rain was correlated or causing the low oil pressure. but how could it?

[ahlem]

Check to be sure your electrical grounds are clean and tight. Moisture may affect cruddy grounds more than on a dry day.

[genphreak]

Vaccum leaks are commonly from the O-rings on the 1" dia crankcase-head ventilation tube. Head removal is probably req'd to inspect, sometimes gently twisting the tube re-seats them. Hard to see, under the manifold, get a good look first so you can be sure what you are doing.