After cleaning up the right side of the engine and replacing all the vacuum lines etc. I find my idle speed is a little higher than expected.

Problem is I can find no combination of tools in my tool box that can get in and turn the 7/32 allen head screw to adjust idle speed.

Wondering if someone can post a pic of a custom tool they have made for this or perhaps is there a Jaguar special tool number or maybe a trick to doing it that I am not thinking of?

 

It's a long allen wrench slightly bent near the center and at the normal 90 degree bend of the wrench, to fit the curves needed to be able to turn it with all the obstacles encountered, if that helps.

A friend made one for me a long time ago. The attached picture does not show the actual tool, but it shows that you also need a shorter section than normal after the 90 degree end has been bent to 45 degrees (the short end of the wrench).

I'll get an actual picture of mine later today.

 

I use an allen key socket....I just happen to have one that's the right overall length to work perfectly.

Everybody has their favorite way of working around this problem :-)

Cheers
DD

 

Just adding my two cents.
Assuming that no one adjusted the idle screw prior to you working on the vacuum lines, Are you saying that you were happy with the idle speed before you replaced the vacuum lines? Did you find any of the vacuum lines leaking? This would account for the change in idle speed. Please verify that all of the vacuum lines are connected exactly where they are supposed to go before you make adjustments. I also have an allen key socket like Doug has. 1/4 drive.

 

Initial idle was a little bit high but it is higher now. Only leaks I found for sure were the boot at the oil breather at the top front of the engine, the bellows for the cruise control, and a cracked vacuum line under the fender near the charcoal cannister, oil dipstick grommet was missing and the oil filler cap 0-ring needed replacing. That said, I replaced all the lines one at a time with black silicon hose just in case there was a leak somewhere. I also sealed some the screw holes in the intake with teflon tape to make sure no vacuum was being lost there.

I did find the lines between the oil breather, air control block and throttle body were partially blocked with oil and carbon. I cleaned everything out including the inside of the intake and the bottom side of the air control block and that may have made a difference also.

I have a 1/4 drive craftsman 7/32 allen socket but it is just tall enough that it hits the side of the air flow meter before it lines up in the hole. Sounds like there is a shorted allen socket out there. What brand of socket are you guys using?

ps. After all this effort, idle has improved and the tack needle is now very steady although I can still feel the engine shake more than I like. Is there a way to tell from the O2 sensor output if the engine is running lean or rich? I have a scope meter and can hook it up to see the signal.