What should I do next? Thought I would get a nice purring cat, and I got hissed at. Here are the details of what I've done:

My 2003 XJ8 was hesitating on pressing the accelerator pedal and seemed sluggish. After reading the forums it appeared likely that the throttle body was dirty and that the MAFS should be cleaned. Indeed after removing the air intake duct I found a TB with a good amount of soot/carbon build up.

Using TB cleaner and a shop rag I cleaned the TB as best I could. I worked around the perimeter of the intake rubbing off the build up, and also cleaned the edges of the butterfly valve. There was some carbon on the ends of the shaft that the butterfly rotates on so I sprayed them directly to clean them off (perhaps a tad overzealous and getting a couple ounces of TB cleaner down the pipe).

Cleaned the MAFS with CRC electronic parts cleaner so no residue would remain.

Also cleaned the air ducting and got oil residue and dirt out of it so it wouldn't be sucked back into the TB.

When I restarted the vehicle I was greeted with a rough idle and the red dash light illuminated.

I suspect that some of the residual TB cleaner didn't agree with the Jag's sensors.

I've disconnected the battery and I'm leaving the car for a few hours to allow evaporation of any residue and for the ECU and sensors to reset.

Help please....

 

I think it would be better if you post in the XJ part of the forum. You will get a lot more technical help and responses. (Or get the moderator to move to the right forum.)

 

Oops, yes. I just read the new user guide and found that there is a XJ specific part of the forum. How do I get a post moved?

 

You might just have some residue working its way through the system. You might just want to take it out on the road and see if you can blow it out.