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myeshia91
11-23-2017, 12:10 AM
Hey there.
I have a 94 525i. In September, I found a lot of oil in the spark plug wells and the car wouldn't start. According to my dad, the cylinders ad whatnot are damaged and I need another engine. Since he will be doing the work, it would be easier for him just to replace the engine. I was going to get a 2nd hand engine from the auto wrecking yard for about $300.

Anyway, They do not have any 94 525i, only 93 and 95. Would either of those work with my car? If so, will I need to get the computer for the engine (or whatever I would need for it to work in my car)?

Thanks.

moroza
11-23-2017, 12:54 AM
There were some differences in electronics, but mechanically the M50TU (92 or 93 thru 95) are all the same. No need for a different computer.

atl530i
11-23-2017, 01:23 AM
Oil in the spark plug wells usually means a leaking valve cover gasket. No start issues can range from a bad fuel pump, faulty fuel pump relay or fuse, or crank sensor to name a few. Maybe even the starter or battery could be causing the problem. 93+ M50tu's will drop in without issue though. You guys should diagnose why it has a no start issue, it could save a lot of time in en engine swap.

myeshia91
11-23-2017, 03:16 AM
Oil in the spark plug wells usually means a leaking valve cover gasket. No start issues can range from a bad fuel pump, faulty fuel pump relay or fuse, or crank sensor to name a few. Maybe even the starter or battery could be causing the problem. 93+ M50tu's will drop in without issue though. You guys should diagnose why it has a no start issue, it could save a lot of time in en engine swap.

Yea, I guess when I changed my valve cover gasket, it didn't line up right. I fixed that leak, but I guess I was too late.

We had changed the plugs, fuel injector railing, ignition boots, fuel injectors, fuel pressure regulator, and tested the ignition coils for spark. Those didn't fix it.

The engine cranks and stays started when continuously given gas, but dies out when not. There is also misfires coming from the engine.

Fuel is making it to the injectors.

A mechanic said it jumped time (he didn't see the car, he only knew the symptoms).

On the day it wouldn't start, my mom said it made a loud clunk noise, but it didn't seem unusual to me. It just sounded like it failed to start, like it has done before.

I was thinking of replacing the crank sensor.

m735is
11-23-2017, 05:19 PM
Recheck all of the vacuum related stuff that you may have removed for the valve cover gasket. It could just be an intake bellow or vac hose that isn't fully seated. You can always check the timing before doing the motor swap.

myeshia91
11-23-2017, 11:48 PM
Recheck all of the vacuum related stuff that you may have removed for the valve cover gasket. It could just be an intake bellow or vac hose that isn't fully seated. You can always check the timing before doing the motor swap.

I'm pretty sure I didn't remove any vacuum hoses when changing the gasket. Also, I changed the gasket a year ago, so it was probably leaking since then.

How would I check if the timing jumped?

m735is
11-24-2017, 01:18 AM
You would have to remove the valve cover and make sure the vanos sprockets are in the correct position when the crank is TDC. Youtube for video on how to do that. Can the motor be turned with a socket by hand without anything hitting?