Author Topic: e30 m42 Firing on only one cylinder.  (Read 2224 times)

phrunt

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e30 m42 Firing on only one cylinder.
« on: September 02, 2010, 10:50:27 PM »
I replaced the coils and does the same thing, sparking only on #1 cyl.

This problem occurred out of no-where. Just wont start.

Any ideas on what the problem is?

Also, the fuel injection is working just fine.
« Last Edit: September 02, 2010, 10:56:39 PM by phrunt »

nicknikolovski

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e30 m42 Firing on only one cylinder.
« Reply #1 on: September 03, 2010, 04:46:56 AM »
Swap in another working engine ecu.

DesktopDave

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e30 m42 Firing on only one cylinder.
« Reply #2 on: September 03, 2010, 09:06:11 AM »
Test resistance of the cam position sensor.  Should be about 1200 ohms.  If that's OK, test the resistance of the spark plug wires (not sure what that value is offhand).

If that's not the trouble, you might have to get another DME as nick suggested.  The high-current transistors in the DME might have been damaged.  They can be repaired if you're good with a soldering iron.

Also, check the codes with a stomp test.  That might give you a hint what's wrong.
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