Broke down, now fine?

[rover215]

I've only owned my '87 325e since Jan 1, and all the driving has been in town. I took it out for it's longest drive yet today. I should mention I tool it to a trusted local BMW shop (Boyd Motor Werks) last week for a bumper to bumper post-purchase inspection (smart, right?) and they gave me a list of all the things that needed attention, but nothing stood out to me as being critical. The valve cover gasket leaks, the oil pan gasket leaks, and there's a bit of oil weeping between the head and block (which they said wasn't that worrysome or even uncommon).

I'd been driving for over an hour at 60-70mph when me and my friend stopped for snacks and a bathroom break. Got back in maybe 15min later and pulled away to almost no power at all. I did notice it sounded slightly odd when it started and had a low idle. I got up to 4th gear but only barely. Temp gauge looked fine. Stopped about 1.2 mile down the road, turned it off, and some smoke started to come from the engine bay. It didn't smell of coolant or even oil, but more like a mixture of things I couldn't pinpoint. When I bought the car I tried cleaning the engine as best I could but it was so sludged up, I couldn't get it all off.

Checked the freshly changed oil- it was good (level and color was good, no bubbles). Temp gauge read just a touch over half way. Called AAA and flatbedded the car home. Got it home about an hour and a half later, cranked it up, drove it around the block and it ran great. It was like nothing had happened to it. I wish I had better diagnostic skills but I'm at a loss. Is my temp gauge off? It starts at below the cold (blue) mark and goes up, so it seems to work.

Makes me want to speed up my project. In the meantime, I picked up a good running M20B27 for $150 a month ago *just in case* this one died. I mean, if I HAVE to, I can swap that out, but I'm planning on a different direction for the future. Anyways, any ideas what happened? Thanks, everyone

[robby41]

ignition switch could be going bad

[Cephas]

Engine speed sensor and crank position sensor. I had an 86 325 that did the same thing. The sensors would test fine per the Bentley until they got to a certain temperature, then they'd go wonky. Replace both, they're cheap.

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[rover215]

Thanks, Cephas- I'll do that. Will report later when they're replaced.

[e30davie]

Stopped about 1.2 mile down the road, turned it off, and some smoke started to come from the engine bay.

Why hasn't anyone asked why there was SMOKE coming from the engine bay?

[rover215]

After posting my reply I immediately wondered the same thing. I might have bad sensors, but why did it smoke?

[e30davie]

well I think only you can answer the question.

if it wasn't coolant steam you need to find the source of this smoke.

[rover215]

I hope to find out why this weekend, fingers crossed.

[Cephas]

I hope to find out why this weekend, fingers crossed.

Not sure how missed that...any updates on the smoke? It didn't smell electrical, did it?

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[TobyB]

...bkuz without knowing where or what the smoke was, it's not very useful
as a diagnostic.

Whatever the fault was, it may have made the engine run lean,
heating things up more, and burning off more 'crud'.
Or it was a stream of coolant.
But you can't smell these things over the internet.

I would rule out the fuel pump, too.

t

[superj]

and, having all those little oil leaks, it could have been oil running down the block and dripping onto the exhaust. my e did the same recently so I finally got tired of people telling me the car was smoking and maybe on fire so I fixed some of the leaks.

now it just smells like its burning, ha ha ha