I thought it was my imagination for awhile, but yesterday I actually witnessed a rapid variation in rpm’s when driving. It’s always when I’m going around 35mph and the rpm’s are around 1200-1400. It almost feels like i unknowingly release pressure on the gas pedal. Thought it was my work shoes. I’m not really too concerned, cause it purrs everywhere else. Any ideas or things to look at?

 

You may want to add an automated signature to your posts identifying model year and engine. This way no one has to assume which one you're driving and can offer relevant advice.

 

Did you finish the top install?



Softball60/Paul

 

I’ve gone through every option in the control panel almost since my first post (multiple people have said this) and I can’t find an auto signature. My year/model is in profile, but that must not be what people are talking about. I’ll try from a desktop at work. 1990/XJS

 

Im done except the rear window. Doing it tomorrow. I washed the top this evening, to have a surgical like setting I have the primer, window sealant, 26:1 caulk gun and Miller Lite, I’ll post results after.

 

I see in your Public Profile its a 1990 XJS V12,

Maybe GGG, AKA Graham, can add your elusive Sig for you, HINT Graham, Please.

Have a read of the sticky I wrote at the top of this section, HE Tune Up......
OK, its Lucas specific, but your Marelli beast is the same for what you are chasing.

Throttle cross rod balance up the creek.
Throttle discs Gummed up.
TPS going flaky
AAV having a Jag moment.
Throttle rod rear bushes missing, COMMON.
Etc, etc.

Miller Lite will help, but some Hi-octane may be needed.

 

My first drive when I got the car home the throttle rod on the drivers side hung up on hose and scared the crap out of me. Thankfully it unstuck after a few harrowing moments, while gauging my distance to the end of the road (figuratively and literally)

it’s a rainy day here in NY, perfect to look over the pieces you mentioned. I will take your advice and include vodka in the line up. This is an eventful day and should be treated as such.

 

If you click on your username in the top right corner, and then go to User Control Panel there should be an Edit Signature button halfway down the column on the left. I have no idea how to get there on the mobile website though.