07 V70 rough/slow start ECM-5000

Flyingfish · Post by **Flyingfish** » 16 Jan 2020, 18:26

The car: 2007 V70 2.5T 139k miles

The codes CEM 9C03(resolved)
ECM 5000

The engine has cranked slow occasionally over the past couple of months. (1/10 times). Then last week (moderate temps 40-50 F) it becomes almost constantly hard to start (about 8 out of ten times). After replacing the three year old battery I finally scanned the codes. I had a 9C03 (this code had been there for over a year...the car worked and I was lazy so I didnt fix it until now) and ECM 5000 so I replaced the immobilizer antenna and the crank position sensor. The 9C03 code is gone but I still have rough starts.

Does anyone have any other suggestions? Ways to test the crank position sensor? I've heard a high draw on the starter can cause interference to the sensor...is it worth pulling the starter?

Post by **RickHaleParker** » 17 Jan 2020, 00:10

ECM-5000 Engine speed (RPM) sensor signal. Faulty signal

Condition
The engine control module (ECM) detects the flywheel position for TDC using the signal from the engine speed (RPM) sensor. The diagnostic trouble code (DTC) is stored if the position for TDC is missing sporadically. The diagnostic trouble code (DTC) can be diagnosed when the engine is running.

Substitute value

The engine control module (ECM) uses the signal from the camshaft position (CMP) sensor if the camshaft position (CMP) sensor has been adapted
Variable valve timing control is blocked.

Possible source

Signal interference
Contact resistance and oxidation
Intermittent fault causes in the engine speed (RPM) sensor wiring.

Fault symptoms

The engine is difficult to start
Poor performance.

Flyingfish · Post by **Flyingfish** » 17 Jan 2020, 15:44

Thanks for the reply...given there hasn't been anything else done that should be causing interference I plan to pull and have the starter tested.

If that all tests ok I'll consider separating out the crank position sensor wire from the rest of the harness and re route it.

Flyingfish · Post by **Flyingfish** » 19 Jan 2020, 17:53

Update:
Three good starts in a row and no codes; the problem seems to be fixed. I pulled the starter and replaced it. I dont have a readily available method to test the amperage under load (the old starter passed fwiw at O'Reilly).

I did not feel like separating out the sensor wires out from the harness. I did however re-secure the harness with various zip ties to make sure it wasnt laying on the starter. The original plastic guide that the crank pos sensor and cam sensors, vacuum lines and coolant pipe are all clipped to had broken and was allowing the sensor wires to get closer to the body of the starter.

So thanks RickHaleParker for reiterating the interference aspect.

Post by **RickHaleParker** » 20 Jan 2020, 00:49

Flyingfish wrote: 19 Jan 2020, 17:53 (the old starter passed fwiw at O'Reilly).

Forgot Where I Was at O'Reilly

Post by **abscate** » 20 Jan 2020, 04:18

RickHaleParker wrote: 20 Jan 2020, 00:49
Flyingfish wrote: 19 Jan 2020, 17:53 (the old starter passed fwiw at O'Reilly).
Forgot Where I Was at O'Reilly

..or did the starter shuffle off it’s mortal coil at OReilly,s?

Flyingfish · Post by **Flyingfish** » 20 Jan 2020, 05:40

Lol yeah I know O'Reilly's. What can I say... they had the part and I need it now not in 2-7 days (or dealer prices).

Post by **volvolugnut** » 20 Jan 2020, 08:41

Good practice is to examine and replace any crumbling wire loom under the hood. It really helps protect wires and looks good too. If you do this replacement, only use wire loom rated for 275 F or above and use good electrical tape like 3M Super 88. Easy project and rewarding in reduced electrical problems and better looks. Also gives you a chance to look for corrosion and chaffed wires.
volvolugnut