searchin99

A recent issue has developed. After the engine is warmed up it has a fast idle of around 1600 rpm or so and won't kick down.

Okay, so it can be any of a million things. I know, I know - needs a diagnostic test.

BUT, before laying out the big bucks for that, does anyone have any ideas of possible fixes?
New air cleaner?
Check some downshift linkage?
Replace some cheap sensor?
etc.?

searchin99

Did some checking under the hood and put a tad bit of pressure on a lever that I think the throttle cable goes to on the throttle valve and it went "click" and the the lever moved about 1/6" to 1/8" then the idle dropped from a fast idle to a normal idle.

Repeated the test a few times putting pressure on the lever and got the same click and normal idle. Tried tapping the gas pedal from the drivers seat and, lo and behold, the rpms dropped back to normal idle.

So, there appears to be something in that mechanical linkage that is causing the throttle to not return to it's normal setting.

For the Throttle valve, the Bently manual says the "stop screw is set at factory and SHOULD NOT BE MOVED." ref. page 25.106. This is for the CIS "Continuous Injection System".

So, what should one do next?

squidix9

Disconnect the cable from the bellcrank to see if it is in the cable or the TB. There are square U shaped clips holding it in place. Pull the bellcrank back and the cable should slip out.

The cable can wear a groove in the sheath causing it to bind. It can be under the dash where the cable feeds thorugh the firewall.

The Throttle plate can also have a buldup by the shaft or where the plate meets the housing. There is also a spring on the shaft which can come unhooked and catch.