Tii Gurus-Need some help

[bmw2002tiidriver]

I have a '72 tii. This is the first time I've had any issues with it besides the starter dying, which was replaced a couple of weeks ago with the e30 M3 starter. On to my problems: it was around 30 degrees this morning, which I think is the coldest it has been started in. It started up perfectly fine. About 5 minutes down the road, The tach, temp, and fuel gauges died. The speedo still worked fine. A couple minutes later, it started running really rough and wouldn't accelerate. I was trying to limp it to work just a couple of miles away, but it died at a stop sign. I called my friend and had her jump me off. It turned over, but wouldn't start. When we took the cables off, I tried again for the heck of it, and it didn't even turn over. My voltage gauge was showing normal voltage, so I don't think it's the battery, which is why I think it's something with the fuel system. I checked my throttle linkages when I replaced the starter, and the were all good. Any ideas on this?

[eurotrash]

Considering that everything you listed is electrical..ly related, even the fuel delivery, I would look at everything from the alternator to the voltage regulator. Blown fuses, burnt wires, etc. Something early in the system has failed. Could be as simple as a bad ground at the battery. Clean the posts.

[Hans]

I think this is another application of the old axiom: nine times out of ten its electrical. This does not sound like a fuel issue. A wild guess is that your battery was slowly discharging, to the point where the car wouldn't run. Perhaps it didnt take the boost because it was flooded? What reading did you get from the volt meter?

[bmw2002tiidriver]

Hans: The voltage meter was reading about 13.5, which is right about what it always reads. Excuse my simple question, but what do you mean when you say the battery was flooding?

[c.d.iesel]

look at your battery cables and connections

look at the back of the alternator - the 3-wire connector

look at the starter motor connections - again

got sound ground cable from the body to the engine block ?

got sound ground cable from NEG batt post to body ?

speedometer is purely mechanical

[Mike Self]

I'd first check that. Pull fuse, clean (and inspect the ends for wear) and reinstall.

If you find the fuse blown, you may have a failing or clogged electric fuel pump. Have you changed the fuel filter recently?

Another possibility: the seat belt warning light sensor in one of the front seats may have failed and is shorting out. That circuit is also on fuse 11, but isn't shown in the factory wiring diagram.

Betcha it's the fuse!

mike

[jgerock]

Agree with the other responders that it is most likely electrical-related.

You mentioned recently swapping in a smaller starter. Are the wires securely fastened to the terminals? DId you somehow break loose or disturb the wiring in the cold start circuit while replacing the starter?

jim

[bmw2002tiidriver]

UPDATES: I took the battery over to Advance to have them test it and it is fine. All ground connections are solid, all starter connections are good, and the three-wire on the back of the alternator is firmly in place. I also forgot to mention that the fuse on the number 11 circuit was blown, and when I replaced it this morning and tried to start it again, it immediately got blown again. I know the fuel pump goes to this circuit, and the symptoms I was having seem to be starvation of fuel. I'm going to go back later and put a new fuse in after unhooking the fuel pump and turn the key and see if the fuse still blows.

[Mike Self]

disconnect the battery and pull up the fuse box. Look at the underside of fuse 11; you should see two white/green wires crimped to the same terminal and obviously factory. The factory wiring diagram only shows one, that goes to the instruments, the other, as it turns out, goes to the the seatbelt warning light, which is triggered by switches in each front seat. When a seat switch shorts out, it'll make fuse 11 blow.

To test 'em separately, you'll have to clip one wire at the terminal. Then test with an ohmmeter on each wire in turn. Infinity means good circuit; no ohms means a short.

happy troubleshooting

mike

[bmw2002tiidriver]

MORE UPDATES: I tried out the wires on fuse 11 and just unhooked the green/white from the "fasten seatbelts" warning on the dash and no more blown fuse! Got it home and then realized all my lights except my headlights work. Any tips on that one?

[Hans]

Things have progressed beyond where I jumped in. By flooding, I meant the engine. But if battery is OK, then we're on to something else. What I find odd is the instruments dying first, then the car. Cleaning the terminals may help. Do you have wiring diagram?

[bmw2002tiidriver]

Hans: the engine flooding makes much more sense. I think I figured out that there is a short in the wire that goes from the seatbelt warning light to fuse 11, which also controls the fuel pump. The short caused this fuse to blow. I disconnected the wire to fasten seatbelts warning, and it is running fine now, sans headlights. My driving lights work fine though, so I should be okay for the time being. I'll sort out the short when I get a chance to dig into the wiring more.

[eurotrash]

good news!!! -mostly.. Nice detective work! ..and a little help from your friends didn't hurt!

[Hans]

There was a post last week about "fuse 11" as I recall. In that case, the pump was drawing too much power. Headlights may be a separate isse.

[bmw2002tiidriver]

Eurotrash: It always is nice to figure most of it out. You guys should have seen the grin on my face when it started. My coworker started laughing and said she'd never seen anyone so happy to start a car. I couldn't have done it without all of you folks' help. Thanks as always to everyone!