Ever since I hooked up my speedo with the Dakota box my idle has been sticking really high when I push in the clutch and when I come to a stop. It sticks between 1500-2000 rpms when the clutch is pushed in.
I drove the car for about 1000 miles with the speedo not hooked up and it didnt really idle this high, soon as I plugged the speedo back in it started doing it. The car runs and shifts alot smoother now its just that the idle sticks when i push the clutch in. Its annoying as hell when I am sitting at a light and its spinning at 1500 rpms or when i go to shift and the idle surges. Its wasting alot of gas plus putting added wear on my engine.
Anyone else have this problem?
Is it a problem with my gas pedal?

 

The ECM needs to see exactly 0 MPH in order to adjust the idle. Check with a scan tool what the ECM reports for MPH when at a stand still.

If it shows 0 then check the IAC counts, if > 0 then something else is causing the ECM to not adjust the idle (coolant temperature is another one that causes no idle control when a 160 deg stat is installed).

If the IAC counts are at 0 then you have a vacuum leak or the TB is sticking open.

Oh, TPS also needs to be at 0% (typ < 2%) for the ECM to control idle. Check that also on the scan tool.

RBob.

 

Exact. Mine would jump up to 1500, but I also saw my speedo jump up because I did not use twisted shielded wire. That set up picks up noise easily, which could be sending just enough counts for the ecm to think that you are moving.

 

My speedo jumps like that as well. I figured it had to be a shielding problem, now I know for sure. What wires are you shielding - the ones from the VSS on the T56?

 

VSS to the dakota box. Would not hurt to do the other one also. One of the city electricians I work with told me to make sure you only ground one end.

 

Can someone explain "shielding wires" to me? Thanks.

-Rippin

 

Easiest explaination would be: wrap aluminum foil around the outside of the wires and ground the foil to the car chassis.

RBob.