new here. had an olds for a while though. not a whole lot of specific info for them out there. it a 97 oldsmobile 88. obviously 3800 v6.

after my research I think im needing to replace the crankshaft position sensor. after yesterday fixing my oil leak. (oil pressure sensor leaked like a siv) I think the oil getting into everything couldn't have caused much good. the car is randomly dying when I come to stop lights to start to slow down. usually dies below 30 mph and when it has reached operation temp for a little bit. also the idle will surge back and forth from 300-700 rpm. yes...300-700. sometimes will die. or it will just keep doing it until I hit the throttle quick .



anyways to get to the point...what is this I hear about a CASE relearn or something after replacing the crank sensor? I've never heard of that. I don't understand why you cant just replace a bad sensor with a good one.

thanks ahead of time .

cale.

sounds more like a vacuum leak, or iac. i would clean the cone and seat and inspect the vacuum lines for cracks or anything looking dry rotted

I pulled the iac a couple weeks ago and cleaned it along with maf and the throttle body.i cleaned the icm connector last night and the car hasn't acted up yet on my way to work like usual. I would think a vaccum leak would be constant and not so inteemittent??

The car runs fine usually until I shut it off for five minutes or so after driving ... Like stopping to fill up with gas after the engine is warm . And when I go to restart it it starts right up and I drove off like normal but a couple miles down the road when I slow down for a street light it will act up . But only after it'* been shut off and cooled down a bit then started back up and run .

Hope this makes sense it'* hard to explain

icm and crank sensor issues kill the engine when they get heat soaked, not make it run bad. the gaskets and parts of the engine and vacuum boots expand and contract and when they get old they cant maintain the seal when warm

That makes sense. It does die quite often though

if it refires fine its not those. but normally vacuum leaks dont cause it to die alot. most of the time if the iac is working properly it will catch and not die. im thinking iac is bad or tps. tps you can test fairly easily. iac not so much without higher end scanner.

https://www.gmforum.com/trouble-shoo...sensor-279319/

what about the ground boss under the carpet on the driver and passenger side...i've already done the driver side one

Ok so it started surging when I pulled into Casey'* on my way home from work to get some windshield washer fluid so I pop the hood and noticed While it'* surging if I pull the vacuum line off of the fuel pressure regulator the idle smooths out and idles fine but as soon as I put it back on it starts surging again. So I must have a vacuum leak somewhere right? I took a video of it surging before I tried pulling the fuel pressure regulator off

Sorry for so many posts but it makes me wait five minutes between editing ... In the above post I meant pulling the vacuum line off of the fuel pressure regulator not the entire regulator I wanted to add that I have a check engine light for an evap code small leak