07 XC70 Cranks, No start, No spark

lightphonics · Post by **lightphonics** » 03 Feb 2019, 14:24

Hey,

Earlier this week my 07 XC70 (149K miles) didn't start out of nowhere. A few days prior I had just driven it 4 hours to Wyoming and back without a flaw, so it was certainly a surprise.

I checked the battery voltage (12.5V), stuck in an extra 2 gallons of fuel as my fuel light had just come on, and stuck in a new fuel filter. I can clearly hear the fuel pump going for 2 seconds when the ignition is on. Also have checked for a good spray from the Schrader valve on the fuel rail several times and that checks out.

I pulled off the engine cover and found some oil had leaked from the oil filler cap onto the ignition coils and area around them. Oil was also in Spark plug sockets and all over ignition coils. Also found that the wiring for the ignition coils had quite a lot of exposed wires, where the wire insulation had cracked over time. I'm sure that must have been shorting out to the engine for a while. I cleaned oil from everywhere, put in new spark plugs, and repaired with shrink tape any exposed knicks in the wiring.

Did a spark test with one of the old plugs connected to a coil and couldn't see any spark. Just tested the camshaft position sensor and am only seeing 5v coming to it from the ECM side. When ECM side is connected up to the CMP sensor then also 5V.

Not too sure what to try next, any ideas would be very welcome!

Post by **abscate** » 03 Feb 2019, 17:52

Both the coil and the spRk plug need to be grounded to test sparks that way, different from a conventional spark check

Fuel pressure gas to be measured accurately , a spritz at the valve doesn’t mean much

lightphonics · Post by **lightphonics** » 04 Feb 2019, 11:52

Update:
After 5 days with no codes being pulled, I finally got a P0336 code today. Crankshaft position sensor is the suspect!

Post by **shiloh51933** » 04 Feb 2019, 13:50

lightphonics wrote: ↑04 Feb 2019, 11:52 Update:
After 5 days with no codes being pulled, I finally got a P0336 code today. Crankshaft position sensor is the suspect!

I'd take timing belt cover off and check everything.

lightphonics · Post by **lightphonics** » 04 Feb 2019, 14:12

Pulled out the crankshaft sensor and I'm getting a pretty low reading of 120 ohms. I hear it's supposed to be more like 200-500?

I have good voltage coming through to the sensor, however when I try to test for continuity on the ground I don't get anything. Could this be the reason instead?

I'm inclined to try a new sensor anyway, but if the ground is bad then I guess that might not do anything.

Where to from here? It seems like an impossible job tracing the wiring from the crank sensor.

lightphonics · Post by **lightphonics** » 04 Feb 2019, 16:46

Upon further investigation, it seems like because this crankshaft position sensor is the inductive magnetic type, the two wires that lead to it are actually just to indicate when there's a signal high and a signal low. (I.E when at dead top center or otherwise). Hoping therefore it must be the sensor or the sensor bracket now. Visual inspection of the bracket looks fine, if there's no change with the new sensor then that's the next bet.