Trying to resolve slight rough idle, found another problem!

So my 97 xk8 has a rough idle. The plugs and coils seem fine, I have cleaned the mag sensor, and I have sprayed around with carb cleaner looking for a vacuum leak with no change. I was looking around the throttle body and on the left side I noticed some cut wires. I’m trying to figure out what they go to, but am hitting a wall. They are orange and black. Not sure what it is, but maybe a cause for the idle?

On my car there is a two pin plug low down and on the back side of the throttle body. It has an orange and black wire going to it, same as yours. The only thing that I can think this feeds is the throttle motor but the wiring diagram shows these wires as being red and green. The wiring diagrams have been known to be wrong, especially about cable colours. I can’t see any other connector on my throttle body with only two wires. My car is the same age as yours.

Have a feel down the back of your throttle body and see if you can feel this connector. The two wires disappear into their own bit of the harness in a convoluted plastic outer.

That is a possibility. I was also seeing red and green mentioned. I could see where the wires went, but wasn’t sure what they were for, or why they would’ve been cut in the first place. Of course I did also remember, when I saw it, that there is a 4 wire connector on the right side (possibly tps) that was cut and spliced at some point in its life smh

Different car being a ‘99 XJR but I have the same slightly rough idle, I’m just living with it, a bit annoying as my S11 4.2 idles steady as a rock albeit in neutral it’s a tad high at 1250-1300rpm but in drive or reverse its at 650 :slight_smile:

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That’s kinda what I have been doing. Living with it. I just figured I’d look into it and see if maybe it was something “simple”

I have replaced all the coils and plugs to no avail so it is what it is.

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