Alarm and limp mode issues

[pondsplants]

Hello
I have 2001 280 dp volvo penta 5.7 pefs 4111650882
My alarm started going off the other day so I took it to mechanic who said the code reader showed two codes
1. No knock sensor signal
2. High ect sensor voltage
They said it might be the Ecu going bad and charged me $300. Told me I should disconnect the alarm and just run it, as the oil pressure and temp are fine.
When I left the marina the alarm sounded instantly and about .5 mile away went into limp mode. Continues to run, but every time I give it throttle past 2500 rpm it idles down.
Where do I start? Ecu is pricey, no?
Thanks in advance for any advice
Chris

 

[gbeltran]

Re: Alarm and limp mode issues

Well, I think I'd find a new mechanic. Sorry, but that's some sh**** advice to run it without the alarm. Knowing it's throwing a code for coolant temp sesnor he should have at the very least checked that circuit, or replaced that sensor.