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allineman
02-12-2010, 01:08 PM
I have a 92 325i that just stalled on the interstate. Fluids are good, Cams are in correst position and gears are aligned. It was running fine but just quit... Why would I get 0 compression on all 6 cylinders out of nowhere?

chromius
02-12-2010, 02:17 PM
What was your method for testing the compression? How do you know it's 0 in all cylinders?

If I was getting a zero reading in all cylinders I would be questioning either my method (gauge not sealed properly), or the gauge itself.

Unless you've got cracked rings, or stuck valves in every cylinder, which is pretty unlikely.

Usually an abrupt stall like you describe is an electrical problem.

InfiniteDice
02-12-2010, 02:35 PM
Broken timing belt or no spark plugs...

Take the oil fill cap off and check that the top end stuff is rotating when you turn the engine over... Most likely you'd be hearing bad things, as valves hit pistons... etc.

Then again it's an e36, different engine. Not sure.

chromius
02-12-2010, 02:42 PM
Broken timing belt or no spark plugs...



M50/52's have chains. Either way though, if pistons were hitting valves it would do more than just stall, it would be making bad noises right before it stopped with a bang.

magnus
02-12-2010, 05:55 PM
Severe gasket fail or you did not test it right.

mirek
02-12-2010, 06:49 PM
Severe gasket fail or you did not test it right.

a gasket failure wouldn't give you a 0, you'd have very low but not 0.

aaron320i
02-12-2010, 09:13 PM
even with no ring youll get more compression than zero. Your not checking right.

ScotcH
02-15-2010, 02:22 AM
Bent valves you'll get zero. Did you money shift? Be honest dude! :)

magnus
02-15-2010, 03:05 PM
a gasket failure wouldn't give you a 0, you'd have very low but not 0.

I used to think the same untill i saw a Rover engine with a severe gasket failure that caused a crack across the head.. Compression was 0.1 at the best case..+
In theory though you are right, if its just the gasked and no head damage.