Throttle problems

[noclutch]

2007 Regal 2000 with 5.0 GXi J/SX-A that doesn't want to hold a steady cruising speed recently. I usually cruise a river and ICW at 25-30 mph ( my best fuel efficiency speed range) and depending on speed limits, but this last weekend once set there I kept slowly dropping speed- over several minutes it would slowly begin to lose 1 mph or two, eventually getting into the low 20's and my mpg would begin to decline decline. WOT and top speed were good as usual, as was acceleration out of the hole and throttle response, so a fuel starvation wasn't on my radar. Throttle handle/cable problems?? I recently did switch from a four bladed SS prop back to the OEM aluminum 3 blades, but I wouldn't figure that to cause this problem. Thoughts?

 

[Don S]

Re: Throttle problems

Is the thottle handle dropping back toward idle? Will it speed back up if you push the handle up. If yes, you might need to adjust the throttle friction on the control. No, I don't know where it's at.

 

[noclutch]

Re: Throttle problems

Thanks Don. If the handle moves (back up over time) it is imperceptible- the difference in the handle position between 2700 and 3000 rpm is not obvious- ie I don't reach down after I see I've dropped speed and say "hey, that has moved up, dang it" :/ If I push down it will speed up proportionally. It does seem that at a slightly higher rpm or speed of say 32-35 mph it may hold better? Not sure there as that isn't as efficient an rpm and I didn't spend much time there. Where I cruise is where it's noticeable.

 

[Don S]

Re: Throttle problems

You wouldn't notice throttle movement for 300 rpm. Move the throttle and find out, If it goes back up, adjust your throttle control friction. Your owners manual may show you where the adjustment is.

 

[noclutch]

Re: Throttle problems

Oh you mean for me to watch the handle after throttling up and note if it comes up, thus putting pressure on the cable to slow engine speed? Gotcha.