To Bob.

[Donald Prater]

Bob thanks for your help on my 2009 Z7 150hp. It was shutting down it turned out to be the water impeller. The motor had on 31.5 hrs on it but it had broke down from not having been used over the winter so they said. I also had an hour meter installed so I could keep up with the hours on the boat. Thanks for your help.

Don

 

[Bob Bourget2]

It is entirely possible. The 2.5 litre Opti's have a very small margin that allows for impeller "wear". Once the pre-determined low value is reached, the PCM will activate guardian. Alarms, and the "miss" warn you to have it checked out. I would be curious to know what your pressure readings are now, vs, then at the same rpm. After scrolling back through the posts, I found your original, and it doesn't really state at what rpm you got those readings.

 

[Donald Prater]

When I get to go to the lake and check it out I will let you know. I do know that my psi when I was having the problem was less then 5 at Idle. That is all I could get out of it because it would go into safe mode when I would try to power up. I will be taking it to the lake this weekend and check it out.

 

[Bob Bourget2]

That's kinda what I'm afraid of.....your motor should have about 2-3 psi at idle......