86 300E Blue smoke out intake, won't start...

Engine turns over but doesn't start, then blue smoke exhausts out the air intake. I've never seen this happen before. Anyone have any idea what this could be?

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What's been done to it?
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On 2006-09-03 12:00:33 -0700, "T.G. Lambach"
Sounds scary and bad. Has there been any timing adjustment or timing chain replacement done to this car? When did it last run?
If it was running and then all of a sudden it does this, I would check the timing chain first, as perhaps that has failed and now the engines lower half is cranking while the valves are sitting open, thus pushing oil into the cylinders and igniting it.
I don't know if this car has an interference engine (ie valves hit cylinders when out of sync) but I suspect it does.
This could mean the head is partly destroyed if my above theory holds true.
Marty
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Geezuz... I hadn't thought of that, but that sounds spot-on. Car has 175K miles on it, engine purred, but in the previous few days it had some hard starts and it was missing occasionally.
Not good news, but thanks for the heads up. I can now be appropriately depressed when I call the mechanic. I had the entire top end of my last one rebuilt at around 295K (215K of them mine), so ugh, I know what I could be in for. That time was elective, not due to a catastrophic failure, so while it hurt, it didn't have quite the same sting.
Thanks again,
John
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Open the oil filler and peer inside while someone briefly cranks the motor. The timing chain is broken if the cam isn't turning. That would be the worst case.
The best case could be that the ignition timing way off for some reason, probably breakage.
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Of course, first check the timing chain.
I is not necessarily that bad:
If the timing chain broke, you would probably have heard an awfull noise when it happened, and I think it is unlikely that the chain has jumped a tooth (perhaps others can tell differently).
I had exactly the same symptom with my 87 190E 2,3 (same injection system). After having checked and doublechecked all timing, the problem showed to be the EHA (the black thing with wires to it located behind the fuel distributor under the air filter).
It's easy to replace, the cost is around 400$, and mine started immediately without problems after having tried everything else for half a year, polluting the engine and spark plugs with all kinds of deposits due to wrong combustion.
We can hope it's just that.
/Jens
PS: The reason why it took so long time to fix the problem, was because I already tried to replace EHA with a used one. But apparently one with the same problem as the original one, leaving me fooled in the troubleshooting. Finally I bought a brand new one. Don't do the same mistake as I did.
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Thanks for all the responses...
There has never been any metal+metal noise, so I don't think the damage can be that severe. I've had nothing but MBZ for 25 years, and this is my second '86 300E, roughly 400k miles between them just on my watch. I've just never had this particular problem. Exhausting out the air intake is something I've never seen...well, there was that '79 BMW 530 Alpina... oy vey.
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snipped-for-privacy@gmail.com wrote:

Have you checked the distributor cap for corrosion or high resistance, this too could cause hard starting and non starts .The blue smoke out of the inlet sounds like the engine backfiring which could also be a bad dist. cap
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snipped-for-privacy@aol.com wrote:

That is what I would check too. I had this problem. Removed the cap, and it was all green inside. I replaced it along with a new seal.
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