1981 320i - Ignition Swtich Problems? Can heavy Keys cause problems?

[320iBodhisattva]

Hey Guys (and I'm sure a couple gals. I'm new to the forum and just getting started on my new addiction. I've owned my 1981 320i for the last 6 years and use it as a daily commuter. So far she has treated me very well, I haven't really needed to do anything to it since I purchased it, except change the oil and a new set of tires. I've put 40k miles on it, well worth the $1,500. I purchased it over other "newer" models as I figured if anything goes wrong, it would be a good learning experience about car mechanics and since there are no electronics the fixes would be more DIY favorable. I've grown to love the little thing, but this month seems to be the time the universe says time to start learning...So I've found myself up late at night reading post and looking at endless threads, diagnosing my latest car troubles. This month I was forced into learning the 320i basics almost something new each week, replaced the fuel pump, fuel filter, distributor cap and rotor, head gasket valve cover gasket, timing issues, and new plugs. This week its THE IGNITION SWITCH. So I think.. This is where I need some help.

I left the keys in the ignition over night last night and today the car wouldn't start. Is a heavy key chain enough to break an ignition switch? The engine doesn't turn over, just nothing. The electric seems to work when the key is in position #2 (dash lights, annoying door buzzer, fan blower etc.) then when I go to start it, the tachometer pins itself and nothing, no sounds. I cleaned the battery terminals and connections coming from the battery, that didn't seem todo anything. Then I got the idea to try a different key. I put my spare key in the ignition gave it a good luck giggle and vroom it started. It wouldn't start with the key that is on the heavy key-chain but does with the lone spare key...? Is this the IGNITION SWITCH? Another symptom I noticed now as well, is when I get the car above 2,500rpm the thermostat starts going crazy swinging back and forth in both directions as the car gets to 3-3.5rpm it almost seems like its going to die, I did push it to 4,000rpm and it died. It still starts with the alone-key and the special giggle but not the standard key (which seems like its a hair smaller or more worn than the spare) still has the problems when getting above 2,500RPM. What do you think?

Is the DIY ignition switch (with key) an easy beginner project? Is this where I should start?

(FYI: I have been using the heavy key chain for the last six years, is there a specific spot in the ignition column that this type of stress presents itself?)

Thanks for your help.

[bitter356]

Welcome to the E21 family! Heavy key chains are a problem I see frequently in my shop. You will need to replace the ignition switch an monitor after repair.