When I start off from a standstill in my '90 XJS I get a miniscule lag that I can feel...the car doesn't stall or anything, but just feels for a second that it could. What do I need to look into?

Thanks.

Submitted by silver007@shaw.ca on Thu, 09/08/2011 - 11:57

those throttle bushings are seemingly always fractured and flopping around as you say Doug.......my throttle pot on Silver is still good after 22 years of my use.....so they should normally be good for 100,000 miles.... mind you they are basically always going to the wide open throttle position..........on Silver...LOL.........FUN FOR SURE.....

Submitted by browder@nuventrs.com on Tue, 09/06/2011 - 09:51

Not sure exactly how badly the head(s) are leaking....enough that the test where the chemical put in the coolant shows hydro-carbons in the system, which may be why despite new radiator/fans/hoses, etc. I was still getting overheating. Not bad enough that water was coming out of the tailpipes. The 'lag" is really a minor thing, doesn't effect driving other than the fact that I am aware of it. Will still get the tech to check it out.

Best,

Submitted by dougdwyer1@com… on Tue, 09/06/2011 - 09:04

As mentioned by George the throttle linakges might need attention: adjustment and/or replacement of the plastic bellcrank bushings.

Make sure the throttle bodies are clean and the throttle blades set to the proper .002" gap.

A worn throttle position sensor could cause a hesitation on opening the throttles.

How bad are the head gaskets leaking? Coolant in the combustion chambers may frustrate attempts at repairing a driveability issue.

Cheers
DD

Submitted by browder@nuventrs.com on Mon, 09/05/2011 - 16:00

Hey SC George, my Jag is still waiting on the tech to get to it....not fixed yet....I will of course provide an update to the forum when the overheating problem is finally resolved. I did post that it has been determined that the head gaskets were leaking, so the heads are coming off when the tech gets to it. Very popular guy... While it is in the shop I am developing a "job jar" of other issues that I want him to check into. Trust me, all of the input and help is most appreciated and an update will be forthcoming when there is one...

Best regards,

Submitted by SE98-32482CJ on Mon, 09/05/2011 - 15:47

George I would check the throttle linkage and switches--but--you are kidding right? You sign back on to talk about wheels and LAG when you have not shared anything about your overheating issues--come on spill it! A bunch of folks tried to help ya out--they deserve a report! Glad it is fixed though.