m20 wont start!!! CPS, battery, and COIL check out fine...

[jlevie]

Do you have spark from the output wire when cranking the engine? No spark could be:

No timing data from the CPS to the DME
No power to the DME (bad main relay, or fusible link) or a bad DME ground
No START signal to the DME
Bad coil or no power to the coil
Bad DME

If you have spark from the coil output but not at the plugs you could have a bad distributor, rotor, or broken timing belt.

If you have spark from the plugs the next check would eb to see what the rail fuel pressure is while cranking the engine. You could have a bad fuel pump relay, blown fuse, bad pump, clogged filter, or bad FPR.

If the rail fuel pressure is normal when cranking, use a noid light to see if the injectors are firing. A bad connection at C191 (underneath the intake) is not uncommon.

[spiDmang]

Then its probably not the CPS.

yup, i realized that...i checked the coil and battery too...still no go.

[N2MYE30]

well, i checked the CPS resistance, and it was reading a solid 532-535 ohms every test...

Then its probably not the CPS.

[spiDmang]

well, i checked the CPS resistance, and it was reading a solid 532-535 ohms every test...

[jlevie]

Check the resistance across pins 47 & 48 of the DME connector, which should be 500-560 ohms. If
the CPS is dismounted, the resistance can be seen to change from about 500 to
540-560 ohms when a ferrous object is brought to the face of the
sensor. Neither pin should be grounded.

[samiam3356]

It should ohm in the low to mid 500's. I have had one check out fine that I swear was still bad. Replaced it with a brand new one and it fired right up. Unfortunatley I replace a couple other things as well so there is no real way to know what the culprit truely was.

[jlevie]

If the allen head in screw is stripped, you can get it out with vice grips. The only tricky parts of replacing the crank position sensor is that you need to set the air gap to 0.040" +/- 0.05" and that the clips on the plastic wire chase will probably break. A new chase and clips should be on hand before pulling the old sensor. Well that and that you'll want to remove the fan and water pump pulley to get to the wire chase.

[spiDmang]

Not to say your buddies are wrong but have you checked the resistance of the sensor before replacing it?

Do have a 5.5mm allen or a standard size to maybe fit in the screw?

yeah, im definitely not forking over money before testing it out!

and i literally just bought some tools, so im gonna get to work.

[N2MYE30]

Not to say your buddies are wrong but have you checked the resistance of the sensor before replacing it?

Do have a 5.5mm allen or a standard size to maybe fit in the screw?

[spiDmang]

awesome, perfect timing!

i actually found it in my bentley (which they called the "pulse sensor")...

i was examining the 5mm hex nut that holds the sensor in place, and that damn thing is stripped...

any thoughts on how i can remove it??

[matthilaman]

dont have a diy but here is a picture of where its located...its the wire in the middle of the picture leading to the little cylindrical metal piece. picture is part of the timing belt diy, might help you a bit.

http://www.r3vlimited.com/board/showthread.php?t=158446&highlight=timing+belt

[spiDmang]

lol so im getting alot of different info here...ill check the location and report back in!

[bmwguy325is]

DUde it is super easy to do. If you can find the crank pulley and the toothed wheel you can replace it.
Argh cant find my book I was going to give you that page #

[spiDmang]

i just did mine its really simple. First of all buy a Bentley manual and that will solve most of your problems.

But the connector is under the diagnostics plug and the wire runs by the w/p and the fan so make you to secure the wire good and the cps is right on the harmonic balancer on the passenger side. I believe its like a 5mm allen key or something like that

hope that helps, and you can test yours by doing a ohms reading on two of the pins and it should read like 500 to 600 hundred or something close to there

im sorry, but huh?? I have a bentley, and ive searched for the "crank position sensor" but i cant find a damn thing within the manual..ill safely assume its named something else in the manual...if so, whats a different name the CPS would go by?

[nomansland92]

i just did mine its really simple. First of all buy a Bentley manual and that will solve most of your problems.

But the connector is under the diagnostics plug and the wire runs by the w/p and the fan so make you to secure the wire good and the cps is right on the harmonic balancer on the passenger side. I believe its like a 5mm allen key or something like that

hope that helps, and you can test yours by doing a ohms reading on two of the pins and it should read like 500 to 600 hundred or something close to there