well guess I should not have counted my chickens - much better running but still not back to 100% normal - just feels like a miss or something not letting it achieve full power when accelerating at speed. I will have to double-check I tightened all that I loosened - wondering if some dirt got sucked in open tube at bottom of throttle body while the hose was off. Maybe some injector cleaner? I did get it warmed up pretty good and ran it up to 60-70 a couple times but not quite. Plugs next I guess..

Make sure that nothing got moved and now keeping the throttle linkage from opening all the way

would you happen to know the part number I need to get the correct O2 sensor - I should replace i t. some have generic ones but I'd rather just be sure I have exact replacement vs. retrofitting something..

Part Number
 

OK, so I have a couple of changes over the years.

Up to '85 I have the p/n: 928-606-124-00

From '86 there have been a couple of supercessions, but will list them in order that they appear in PET (oldest first):

930-606-124-00
965-606-126-00
965-606-126-01 (most recent I see).

Can be found from or host at: Pelican Parts - Automotive Parts and Accessories - Porsche & BMW for about $134.

Should anyone else have more technical detail, please chime in, as I have not played with O2 sensor on mine, as it doesn't use it (ROW car) and am not sure on the two wire / three wire discussion.

Cheers

thanks Skip - yea the multiple wire varieties is where I'm getting confused (not that it takes that much) as I don't yet know which flavor is on the car now.. just want to get plug and play replacement vs. me having to do wiring which I could screw up and just add to the issues as I continue trouble shooting process on poor running motor...

Yeah, probably prudent to take a look on the engine to make sure (check connector in the engine bay too).

update - swapped out a different O2 sensor and noted some improvement. (The right tool for this made it 15min job). Checking oil later, I found a another vac line off - this one was on right side up and behind the oil filler area - it comes from under the airbox up to top of a small 3" cannister looking thing which had a nipple on top and it must have pulled off when I changed out the air filter. Car runs much much better - will get plugs done as I think still think there's possibly a fouled one affecting acceleration/engine smoothness.

new plugs fixed all issues - two were pretty bad - one possibly not even firing - this plus other issues cleaned up have got this car running very well. Everything I replaced in past few months were maintenance items not covered in PO's work records so not bad investments. 70 + here today - blew out some carbon on a nice run.

ALL GOOD!

BEST!

Doyle

Post some pics of those fouled plugs. Would be interested to see what they look like. Possibly some valve guide leakage causing the fouling.

glad you mentioned that - no pics I pitched them unfortunately but I will say the worst one was #6 which showed a lot of burned oil and was even a bit wet - tech noted I had filled the oil to second mark and reminded me to never do this and felt this was likely cause of the fouling- I have read previously they do not like the oil filled any more than the halfway point between the two marks, but I forgot this when I topped it up last Fall and sure enough, my problems started right after that. SO... lesson learned and shared with anyone who needs to know - DO NOT OVERDO IT WHEN TOPPING UP OIL LEVEL - FILL IT ONLY WHEN HOT AND NO MORE THAN MIDWAY BETWEEN THE TWO MARKS.

Yeah the oil level 1/2way is a general rule of thumb. Some racers fill it all the way up and i'm not sure why.

I can attest to the overfill fiasco. Even a seasoned vet like me can do it. Forgot to drain the sump when sitting in storage. Filled up too much and POOF massive smoke screen and muffler filled with oil. Major PITA to get rid of that mosquito fogger problem.....