BMW E46 Fanatics Forum banner

1 - 20 of 33 Posts

·
Registered
Joined
·
30 Posts
Discussion Starter #1
Hello gents,

Thanks in advance for any help or direction you can point me in to get this thing running and out from under my wife's carport:D

Looking for some help diagnosing a 2001 325i m54 that wont start after engine swap out of a 2004 325i m54. The 2004 engine was running prior to transplant. Transplant occurred because the 2004 had a dash-fire that ruined the interior. The 2004 was almost mechanically perfect. Interesting--- I discovered during this swap that it has/had a 3.0 liter engine. Figured this out because the DISA valves were not the same size for the 2 cars prompting me to dig further. To the best of my knowledge my 2004 donor car was not suppose to be a 3.0 liter car.

Maintenance and running history are unknown or suspect on the 2001 recipient vehicle. The seller told me it had been running but overheated and warped the head. During the swap I found a few wiring "repairs" in the main harness that had me scratching my head "why?" (not the cars first engine swap??) so I upgraded cleaned them up with a soldering iron and shrink tubing. I also discovered that the car has been in a right front fender bender--some of the front sheet metal and panel lines are a little off (project for another day).

I've pulled and installed engines before--but never this extensive with this much plastic and sensors/controls. I took my time and spent the last couple of weeks replacing all the rubber and plastic and dealing with odds and ends to make this as reliable as possible after I get it done. There were some minor differences going from and 2004 to a 2001 in the wiring harness and emissions controls but otherwise almost everything was plug and play though I did have to change a few sensors out from 2004 to the 2001 (O2 sensors etc...)

Put the battery, oil, and antifreeze in it this AM and attempted to start. After a couple of cranks I bled the air out of the Shrader valve on the fuel rail to check the engine is getting fuel and to get the fuel to the injectors faster.

At this point it will crank but wont start. Is there any thing I have to do to the computer to complete this swap?

What's the easiest way to make sure its getting spark?

Any suggestions on things to check and make sure I didn't overlook would be appreciated.
 

·
Registered
Joined
·
3,841 Posts
Could be due to a number of reasons, but let's get some additional information here since the new engine likely came with wiring harness for MS45 DME, but your 2001 model should have the previous version engine management MS43.

When people do this kind of swap, they usually transfer the old wiring harness to the new engine, which may also require the old style coils, valve cover, MAF sensor, oxygen sensors, secondary air pump, etc. Not necessarily the only possible route, but surely the most straightforward, especially for someone who hasn't got a lot of experience with E46 BMWs.

Thus it would be helpful if you can describe in more detail what wiring and sensors did you transfer from the 2004 to the 2001 model and how.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #4 (Edited)
Could be due to a number of reasons, but let's get some additional information here since the new engine likely came with wiring harness for MS45 DME, but your 2001 model should have the previous version engine management MS43.

When people do this kind of swap, they usually transfer the old wiring harness to the new engine, which may also require the old style coils, valve cover, MAF sensor, oxygen sensors, secondary air pump, etc. Not necessarily the only possible route, but surely the most straightforward, especially for someone who hasn't got a lot of experience with E46 BMWs.

Thus it would be helpful if you can describe in more detail what wiring and sensors did you transfer from the 2004 to the 2001 model and how.
-----------------
I was real careful to observe any differences between the two wiring harnesses. Only real differences that I noticed were the O2 sensor jacks were different and there was an extra connector/wire for the vac control solenoid for the SAP (attached to rear of intake). MAF was also different and I used th 2001 (recipient vehicle) MAF.

While the coil setup is different It did connect to the DME so Im hoping I wont have to change cause the old valve cover is cracked and broken from overheating. Had to solder different power supply jack in the control box (2001 harness was damaged). This is only harness I used from the 2004---was hoping to use the 2004 coils.

I used the 2001 wiring harness that had all of the sensor connections(bolts below the intake on Left of engine). No modifications made. no sensors needed or swapped.

Used the 2001 O2 Sensor and injector harness but had to swap the 2004 sensors out for the 2001s
 

·
Registered
2004 325i automagic
Joined
·
2,526 Posts
When people do this kind of swap, they usually transfer the old wiring harness to the new engine, which may also require the old style coils, valve cover, MAF sensor, oxygen sensors, secondary air pump, etc. Not necessarily the only possible route, but surely the most straightforward, especially for someone who hasn't got a lot of experience with E46 BMWs.

Thus it would be helpful if you can describe in more detail what wiring and sensors did you transfer from the 2004 to the 2001 model and how.
What about the Intake Air Temp sensor? On the newer cars It's part of the MAF sensor housing while on the older cars it's located on the intake manifold, is it not?

OP, is there an extra connector from the old wiring harness in middle of intake with no where to plug into?
 

·
Registered
Joined
·
8,568 Posts
For an MS45.1 swap to a MS43 to work, you swap over the valve cover, coils, maf, intake air temperature sensor, and o2 sensors. You also need to reprogram the DME using ncs-expert. All you need is a $15 inpa cable. Make sure you didn't swap any connectors. When cranking, does the tach rpm go up to 250?
 

·
Registered
Joined
·
30 Posts
Discussion Starter #8 (Edited)
What about the Intake Air Temp sensor? On the newer cars It's part of the MAF sensor housing while on the older cars it's located on the intake manifold, is it not?

OP, is there an extra connector from the old wiring harness in middle of intake with no where to plug into?
---------------------
Pulled that off of the 2001 (recipient car) and plugged into the 2004 intake (donar engine). Since I used the 2001 injector wiring harness it wasn't a problem. There is still a port for it in the 04 intake casting---my 04 had a blank plug in that port.\


thanx for your respose
 

·
Registered
Joined
·
30 Posts
Discussion Starter #9 (Edited)
For an MS45.1 swap to a MS43 to work, you swap over the valve cover, coils, maf, intake air temperature sensor, and o2 sensors. You also need to reprogram the DME using ncs-expert. All you need is a $15 inpa cable. Make sure you didn't swap any connectors. When cranking, does the tach rpm go up to 250?
----------------------

After I read Megalocnus questions I went back and took a look at how the 01 is wired at the DME plug and how the 04 is wired at the DME plug---they ain't the same :thanks:--Missed that when I was determining whether to use the 04 or 01 coils and coil wiring harness.

Already swapped the O2 sensors, SAP control solenoid, MAF, and air temp sensor

Gotta go hit my fav junk yard and see if I can find an intact valve cover. the 01 valve cover is cracked and the wiring harness is heat damaged




thanx for the response
 

·
Registered
Joined
·
1,192 Posts
The coil harness is different I believe. Compare the wiring diagrams at www.newtis.info I have heard that you can just swap some pins around in the dme connector of the ignition coil harness.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

·
Registered
Joined
·
3,291 Posts
Start with the basic: sparks and fuel injected.

Remove one plug and coil and lay them down, connect to harness, plug touches metal ground. Watch for blue sparks when crank, and fuel mixture shot out the plug hole.

Measure fuel pressure should be around 50psi. Listen for injector clicking during crank, and smell fuel at tail pipe .
 

·
Here to serve y’all
2004 330Ci 85k miles
Joined
·
12,756 Posts
For an MS45.1 swap to a MS43 to work, you swap over the valve cover, coils, maf, intake air temperature sensor, and o2 sensors. You also need to reprogram the DME using ncs-expert. All you need is a $15 inpa cable. Make sure you didn't swap any connectors. When cranking, does the tach rpm go up to 250?
OP doesn't need to flash the DME. He swapped the 2004 B25 motor into the 2001 and retained the MS43 DME as well as all of the 2001 engine peripherals, except he used the 2004 valve cover, coils, and coil harness. That's where the problem is. If he re-pins the coil wires at the DME connectors and validates the other important signals there, he should be good to go.

Or, if he gets a coil harness from a 03/2003 or later 325xi or 330xi, it should be plug and play, because those cars have the MS43 DME with the new push-on coils.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #14
The 50's kid repinned the connector for the DME when he did an M56 valve cover on an early engine that had the bolt on coils. Maybe you need to do that too, just a thought.
------------------------------

Just watched the 50s kid video---thank you!

https://www.youtube.com/watch?v=lx3Wqy27Go8

This is the route Ill take in the morning--Re-pin the DME plug for the coils.
 

·
Registered
Joined
·
30 Posts
Discussion Starter #15
The coil harness is different I believe. Compare the wiring diagrams at www.newtis.info I have heard that you can just swap some pins around in the dme connector of the ignition coil harness.

Sent from my SAMSUNG-SM-G870A using Tapatalk

The coil harness is different. Thanks for the link---it will be very useful in the morning



thanx
 

·
Registered
Joined
·
30 Posts
Discussion Starter #16
Start with the basic: sparks and fuel injected.

Remove one plug and coil and lay them down, connect to harness, plug touches metal ground. Watch for blue sparks when crank, and fuel mixture shot out the plug hole.

Measure fuel pressure should be around 50psi. Listen for injector clicking during crank, and smell fuel at tail pipe .

Thanx for your response...Your thought process mirrored mine. Gotta have air, fuel, and spark to make it run. I was getting the air and the fuel but no bang.

Ill put the fuel pressure gauge on tomorrow and make sure Im getting 50 PSI. I wasn't sure how much PSI I was 'spose to have---was going to look up tonight. You saved me a search.
 

·
Registered
Joined
·
8,568 Posts
OP doesn't need to flash the DME. He swapped the 2004 B25 motor into the 2001 and retained the MS43 DME as well as all of the 2001 engine peripherals, except he used the 2004 valve cover, coils, and coil harness. That's where the problem is. If he re-pins the coil wires at the DME connectors and validates the other important signals there, he should be good to go.

Or, if he gets a coil harness from a 03/2003 or later 325xi or 330xi, it should be plug and play, because those cars have the MS43 DME with the new push-on coils.
Of course he doesn't need to but why not if he upgraded from a B25 to a B30
 

·
Here to serve y’all
2004 330Ci 85k miles
Joined
·
12,756 Posts
Of course he doesn't need to but why not if he upgraded from a B25 to a B30
Not sure he did upgrade to a B30. I was wondering if the donor is a SULEV B25, as that would explain the B30 DISA and MAF making OP think the donor engine is a B30. The M56B25 (SULEV) uses the B30 DISA and MAF.

DISA for M54B30, M56B25 (SULEV): 11617544805
DISA for M54B25: 11617544806

MAF for M54B30, M56B25 (SULEV): 13627566983
MAF for M54B25: 13627566984

OP, did the 2004 325i donor car***8217;s engine cover look like this M56B25 SULEV?
https://goo.gl/images/qWZcMP
Or, did it look like the M54B25 and M54B30 one?
https://goo.gl/images/3iXrvm
 

·
Registered
Joined
·
8,568 Posts
Not sure he did upgrade to a B30. I was wondering if the donor is a SULEV B25, as that would explain the B30 DISA and MAF making OP think the donor engine is a B30. The M56B25 (SULEV) uses the B30 DISA and MAF.

DISA for M54B30, M56B25 (SULEV): 11617544805
DISA for M54B25: 11617544806

MAF for M54B30, M56B25 (SULEV): 13627566983
MAF for M54B25: 13627566984
Interesting point you brought up.

Op can you post the last 7 of the Vin of the donor car and pictures of the engine bay please
 
1 - 20 of 33 Posts
Top