I do believe OP’s car has an early EFI setup, but it did have a vane air flow sensor, NOT a MAF
I believe you’re thinking of the K-Jetronic mechanical fuel injection system. Believe it or not, parts are not particularly difficult to find, as that system was used on Audi, VW, Benz, Porsche, etc. for many years. Some were wise to get rid of it fairly early, while Benz kept it through 1993
Benz loved the old mechanical system…It had served them well ever since the late 1930’s and their prized DB-605 aircraft engine…
Most of the problems I’ve seen with AFC systems usually involves air leaks, engine temp sensors, or the air meter itself.
While I can’t speak with any authority on the early BMW systems as I am just not familiar with the details, a flaky double relay on cars with similar FI systems can create intermittent and/or odd problems due to burned contact points which may cause the fuel pump or ECU to kick in and out.
Nice looking car in the pics. It would be a shame not to get this sorted out; and you do not want to go for the Audi.
The Miata; maybe. 
MAF is Mass Air Flow sensor…on top of ur motor usually, google it (one of those ‘shot in the dark’ ‘could be’ diagnosis’
oh, and this WILL continually get worse…and quickly too. Sadly this is just what happens to vehicles after a certain amount of time/or crap in the system… i find all my fords n chevys do this at about 10yrs of age. get a new cat converter asap.
WELL THEY WONT APPROVE MY FIRST COMMENT. lame! i’m appalled at the answer u got earlier )
ill try2quickly sumerize-U need a cat converter. Ive done this myself, hardest part is breaking exhaust bolts, lotsa wd-40. and a breaker bar 4 leverage if needed…HOPEFULLY if ur lucky you only have 1, some vehicles have 4…they are $80-300 a piece! so hopefully u dont have multiple cuz THEY WILL ALL need replaced…if u hav 4 n can not afford them, id do 2in the SAME LINE they will help. dont do 1 on ea side as they dirty 1 will not allow the new 1 to help. ANYWAY, SOME vehicles have these WELDED in, thats NO GOOD cuz u have to BUY A WHOLE EXH. SYSTEM…$$$ mine was $500 sum for a 99 mustang that had 2 ‘cans’ (cat converters). IF THEY UNBOLT, YOUR WELL OFF! MAKE SURRRRE u find an EXACT OEM MATH online, aftermarkets VARY greatly in the flange TYPE, SIZE, and even the ROTATION its set in…the pic may look the same, but when its turned the right way under ur car, the holes dont line up. SOME places GUARRENTEE a perfect stock fit 
they r heavy to ship, so add that when ur shopping. AGAIN even if u pay 400 in parts, this is a high priced shop job and ur gonna save $300+…call around 4 a quote for removing and replacing a cat converter for ur car, tell them JUST LABOR, no parts. then decide. IF this is BOLTED, u can do it, no prob… giv urself lotsa time before ur trip though ur NOT gonna do it fast unles ur bolts r not heat sealed together…**WIRE BRUSH IT really GOOD AND soak IN WD-40 OR EQUAL in ADVANCE…then do it AGAIN…break them all loose in advance!!! save ur self time n energy. u can have them ALL ready to remove by the time ur part arrives, then it’ll b a quick job. perhaps do that before u decide to fix it urself…u may not be able to break em urself.
Why a new cat?
OP’s car has a volume air flow sensor, not a MAF
“i’m appalled at the answer u got earlier”
Please explain
oh! lol and REPLACE IT WITH NEW BOLTS/WASHER/NUT!! AND SOPRAY N GREASE THEM SO NEXT TIME U DONT HAVE THIS ISSUE. lol…sorry i’ll shut up now
I WAS REFFERRING TO HER PHONE CALL ON THE RADIO. because the cat converter(s) is what it is. they r clogged with soot and her exhaust air is starving her engine of oxygen which is why it has no power and sputters, likely seems worse uphill, its extremely inconsistant, loud, and sputtery, cuts in n out and u have to floor it just to go 40mph…i dont know how more of you arent familure with this problem
Uh, @hotrodroxie, the first in this thread was in April. This online request is in no way related to the show, which is in reruns.
Besides, if you review the posts, OP has already replaced the cat, to no effect. Why do you think she should replace it again?
I can understad an honset mistake on your part, but to come to this forum and insult long-standing members (who are only trying to help, and for free at that) rubs certain people the wrong way. Like me.
BTW, you can have a welded cat cut off, and a new one welded in. It’s not particularly hard, either.
Yes. Cat was replaced May 30. It still ran crappy after that. It seems to have been worse in damp weather, but that may have been me grasping at straws. It is running okay now – even when it rains and is damp out. It starts every day since the ignition coil was replaced. No more sputters and cutting out for the last few weeks. It is still a little slower than I would like going up hills. I have not done any new work to it. It just started running better. That seems to be the way it goes with this car. I definitely want to get another car for the winter. I like the miatas and the boxsters that you guys suggested, but I don’t think those are good winter cars for me. I’d like to get something FWD. I saw a 2002 celica the other day that looked nice, but they wanted $8000, which I thought was insane.
@lealea - have you asked around the BMW boards for a mechanic in your area? I’d try and find an ‘old BMW whisperer’ that you could go to and have them give it a good going-over? Honest, it’s approaching ‘antique’ status, if you want to keep it healthy it’ll take some work.
Where are these BMW boards you speak of? On this site? I would love to find an old BMW whisperer!! That’s exactly what I need.
There are several, you can google ‘BMW E12 forum’ for more (your chassis is the E12 version of the 5 series, the first one).
Here are a few:
http://www.firstfives.org/
http://www.bimmerfest.com/forums/forumdisplay.php?s=d06eaea50e7a175e0fedee5d83b97023&f=111
http://www.bimmerwerkz.com/forum/5-series-e12-e28-e34-e39/
http://www.bmwcca.org/forum/index.php?forums/e12-1975-1981.20/
thanks a million!!
I checked the ‘mechanics files’ link above, turns out “Phil’s Foreign Auto” in South Portland works on these, here’s what Bruce (the owner) had to suggest in an email:
“Easy things first. Check the vacuum line to the fuel pressure regulator and see if there is any fuel there (there shouldn’t be). If there is, the fuel pressure regulator should be replaced. Next item would be to check the resistance of the coolant temp sensor. These are notorious for having bad connections on them. Make sure contact are clean and check the resistance with a DVOM. Anything more than 600 ohms when the engine is warm, replace the sensor.”
You might look them up next time you’re in the area.
Wow. Thank you so much!
Not sure if you have your car fixed yet but one thing that I haven’t seen anybody mention is if you’ve made sure that the spark plug wires are you put on your car are the correct ones because it does make a difference
The person asking this question has not been for 4 years while your advice might be good most likely the person has solved their problem by now.