dt150 2000 tps adjustment problem

[msilvast]

Hi, my dt150efi from 2000 run a bit rough on idle. It also consumes gasoline more than it should and smokes more than it should. Spark plugs are never dry, but bit oily. It gives all the power it should and runs ok on cruise.
So I started to go through the fuel system. Replaced some lines and filters as thy were past their best before date.
Today I was checking the TPS. Sensor itself seems to be ok. Then started to go through the adjustment procedure. V1 measured 5.00 and v2 should be .600. Ok, did the adjustment, but then after it was fine, touched the base where the TPS is attached and the adjustment went way off. I realized that the base plate is not very firmly attached to throttle body. The plate is attached via so rubber mounts and there is some slack. I actually can move the plate so that v2 changes from .53 to .73 volts. So setting the sensor with the required accuracy is a bit difficult.
So the question is; should the plate be mounted with these rubber things and should they be firm enough not to allow any movement on the base. They looked like originals, but as they are not a really moving part, hard to imagine they would wear out. Or is there something I'm missing?

[Solarman]

My TVS, dt140, efI, has rubber mounts on the base plate to the throttle body, but the TVS itself is a plastic housing that mounts to the base plate securely with its own set of screws.
And, my rubber mounts don't seem to move at all? I'm not sure I can visualize your TVS still moving?

Post back.

[msilvast]

Yes, tps is securely mounted onto plastic plate, the plate itself can move as the soft rubber mounts don't keep it still. Just by turning the base plate I was able to get .2 volts difference in v2 reading. The plate is really quite loose even though the bolts are tight, it is just those rubbers which allow the movement.

[Solarman]

Then maybe the rubber spacers should be replaced (yours may be dry rotted and soft?), or if it is the plastic base sliding maybe add a small flat washer on top of plastic to tighten to plate better.
I don't think a new TVS is needed.

Good luck.

[ScubaSteve]

Have you checked the fuel pump? Sort of sounds like the symptoms I had before I replaced mine.

[msilvast]

It is on my check list. It looks like if there is any issues with that it needs replacement. I need to check where to get a new one before trying to do something. The TPS mount plate now sits quite firmly in its place after some tweaking of the rubber spacers. Need to adjust it tomorrow.

[msilvast]

Finally got the boat into water. Rough running on idle and low rpm was pretty much gone. Also smoking was almost gone, but the day was so warm, that need to verify it on a colder day.
Maybe next week I'll take the boat for longer trip and then we see if the fuel consumption has gone down or not.
Thanks Solarman.