Volvo-Penta 5.7 Gi idles at 1800-2000 RPM

[Firefighter5602]

So I'm back! lol I got the timing set and it still didn't make any difference. I ended up taking it to another shop to have it checked out. They found that the previous shop had installed some wrong parts and thinks that the ECM is either bad or not for my engine. We are having it tested to see. One of the incorrect parts was the TPS. Apparently there are 2 different types of TPS for this throttlebody. One works forward and the other works backward. The previous shop had the wrong one on mine so when I would throttle the boat out of idle the TPS showed it being in full throttle and decreasing the throttle as I would actually throttle up. After changing that, the plugs (wrong TPS caused plugs to foul) and a couple other adjustments made the boat run 100% better. Since this was done at the end of the season I haven't been able to take it out and it is now winterized so it will be spring before I can get it back on the water. We are taking the ECM out this winter to have it tested and checked to make sure it is doing what it should be.

I have also found a bent propshaft and bad u-joints on the driveshaft on the DP-S duoprop outdrive so we are replacing those this winter as well. I am also having the props repaired since they had some nicks out of them.

I just felt like I should keep all of you guys informed on what I'm finding since you have been awesome at giving me advice on what to check and how to do it. I'll keep posting as I go and will let you know how everything turns out. Thanks again for all the help!!!

Doug

 

[alldodge]

One of the incorrect parts was the TPS. Apparently there are 2 different types of TPS for this throttlebody. One works forward and the other works backward

Appreciate the update, am puzzled with the TPS being backwards. Do understand how it should work but ok, learned something today