So, I'm here with a few more pages to add to my Multistrada saga. But I want to say first and foremost that I'm so grateful for those of you who have given input on this problem I'm having. It's given me many avenues to explore that I would be otherwise ignorant to. So, seriously, thanks everyone!
I've been reading over the shop manual about the operational principles of the engine control systems (I feel like a nerd just writing that)
. One of the major take-aways with the MAP sensors is that if one is throwing a fault (open-circuit or whatever) the ECU will use the information from the other sensor for BOTH cylinders. It will still throw a code, but the bike should, in theory, run normally. So, I tried to test that theory and either confirm or rule-out the hort. cylinder MAP sensor being the problem.
I unplugged the hort. cylinder MAP sensor and ran the bike.
You would think it won the lottery with how rich it was running. It was also backfiring and stalling out. The bike didn't want to rev up and when it did, it had a fit. But it never threw a code.
I'll say that again: never threw a code.
I ran that engine for at least a minute and didn't get any information from the ECU on the dash nor a CEL. Per the manual, it's supposed to throw a code when it senses an open-circuit going to either (or both) MAP sensors.
I plugged the sensor back in and the bike returned to how it has been running for the past few weeks? months? I don't remember when this even started anymore.
This leaves me with a few questions:
Why on earth did it not throw a code?
How often does the ECU check for an opened circuit (maybe I didn't let it struggle long enough)?
Why did it not switch over and use the other MAP sensor for the vert. cylinder like the manual says it should?
Does the fact that it ran worse mean it isn't the MAP sensor at all and I'm just chasing a wild goose?
If I don't get any clear answers on this, I'm just going to move on and check the hoses to the MAP sensors, like mwhite5471 suggested. If it isn't that, I'll move on to the injectors like wal916 and Steve W. suggested.