955IsAlive
New member
- Joined
- Apr 22, 2018
- Location
- MN
[Resolved] 960 Misfire + P0340 (Cam Sens Circuit), no Misfire code
Summary:
A 960 on Motronic 4.4 will run with a missing cam sensor signal, but it will not run well.
The engine will crank for a little longer than usual when you are starting the engine.
You'll experience power loss, increase in fuel use and possibly find the engine stumbles/hesitates under certain conditions.
You can test the cam sensor with this procedure. Nb, the voltage on pin #2 will be battery voltage, not 5v:
https://www.youtube.com/watch?v=cB1VEfjGz1c
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The 960 developed a misfire/cut/falter of some sort yesterday. Here's some details...
Occurs around at 3800 RPM under heavier load (75% throttle or more). I'm guessing 3800 is around peak torque for a B6304?
Also in happens in neutral, no load around 2800.
When the misfire started to happen, check engine light came on for P0340 Cam sensor circuit
There are no codes for misfires, nor has the CEL flashed which I thought was odd. (I thought M4.4 supported misfire reporting?)
Today I reseated the connector/cleaned the connector for cam sensor and the codes comes back immediately after being cleared.
Ran without the MAF incase there was something weird happening. No change.
Plugs are fairly fresh, probably less than 2K miles on them.
Planning to plug a multimeter into the pins for the cam sensor shortly.
So my first question is....
Are the cam sensor code and misfire\cut likely to be related, or am I looking at two separate issues?
(Edit) Answer: Yes cam sensor controls injection and ignition timing.
Summary:
A 960 on Motronic 4.4 will run with a missing cam sensor signal, but it will not run well.
The engine will crank for a little longer than usual when you are starting the engine.
You'll experience power loss, increase in fuel use and possibly find the engine stumbles/hesitates under certain conditions.
You can test the cam sensor with this procedure. Nb, the voltage on pin #2 will be battery voltage, not 5v:
https://www.youtube.com/watch?v=cB1VEfjGz1c
-------------------
The 960 developed a misfire/cut/falter of some sort yesterday. Here's some details...
Occurs around at 3800 RPM under heavier load (75% throttle or more). I'm guessing 3800 is around peak torque for a B6304?
Also in happens in neutral, no load around 2800.
When the misfire started to happen, check engine light came on for P0340 Cam sensor circuit
There are no codes for misfires, nor has the CEL flashed which I thought was odd. (I thought M4.4 supported misfire reporting?)
Today I reseated the connector/cleaned the connector for cam sensor and the codes comes back immediately after being cleared.
Ran without the MAF incase there was something weird happening. No change.
Plugs are fairly fresh, probably less than 2K miles on them.
Planning to plug a multimeter into the pins for the cam sensor shortly.
So my first question is....
Are the cam sensor code and misfire\cut likely to be related, or am I looking at two separate issues?
(Edit) Answer: Yes cam sensor controls injection and ignition timing.
Last edited: