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Recommended Posts

Posted

I'm troubleshooting an issue with random rough running values below 2.0, infrequent and random hot re-start idle stumble (difficulty holding 680rpm momentarily), and stalls once or twice after hot and idling.

I've already located the specs for the crank sender and ohmed mine out at 839 at 50F, which I understand is within spec of 800-1000 ohms, however closer to the "tired side" as I've read people with new sensors have read closer to 950 ohms. I plan to artificially heat the sensor and re-test.

I'm hoping it's not an issue with the DMF, but want to also rule out the cam senders as well. I think I will replace the crank position sensor regardless, since it is a $100 or so part and easy to get to.

I can't find any specs on what the cam position sensors should ohm out at or which pins to test.

Thanks in advance if someone has those specs.

(no codes of course). ;)

Posted

Did some digging on the wiring for the cam position sensor, looks like I need to ohm out pins 1 & 2, I'm just not sure what the acceptable ranges are.

5.2.2 DME

pin 1 cps

pin 34 dme sensors ground

x59/2 pin 21 (engine harness location)

pin 2 cps

pin 21 dme hall sensor signal (both sensors on same wire)

x59/2 pin 14

pin 3 cps

pin 53 dme 5v supply

x59/2 pin 22

Posted (edited)

For the cam sensors:

From the DME, getting 4.98 volts on pins 1 + 3 and no short between 1 + 2.

Tried ohming bank 2 sensor but don't get any readings from it. Bank 1 sensor is too hard to reach to test electrically, I would have to remove the sensor which means removing the AOS.

Anyone have an o-scope I can borrow? :|

CPS.PNG

On the subject of the CKS (crank sensor) I heated it up using a heat gun to similate running condition, and it read anywhere between 1005 ohms (hot) to 841 ohms (once cooled down) steady both readings. Is it possible the sensor is bad even though it ohms out OK? I hate to throw away money.

Read more about tshooting DMF, short of removing the transmission and replacing the DMF, I can't see any other way to test this easily without an o-scope.

RMS.PNG

Ideas are welcome!

Edited by logray

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