Hello all, this is an odd question but here goes...

When the secondary tensioners begin to fail do they cause the idle to run a bit rough, and would that cause an error code?

I have a standing appointment to have the secondary tensioners done in 2 weeks but I drove the car last night and the check engine light came on. (in the left instrument, not center)

I had wanted to fix them pre-emptively, aka they haven't already snapped. The shop that's going to do it for me once asked "is the car starting to idle rough"? I answered no, but I do now notice that the idle cyclically surges maybe between 750 775 750 775.... over say 15 seconds.

anyone want to gander a guess at whether or not the check light and tensioners are related?


2000 xk8, 75k miles

 

the best thing would be to get the code read. Any local parts store should do it for free. then once you know the engine code we will be able to better assist you.

 

Chances are it is unrelated to the tensioners, unless you hear strange noises from the engine, especially when cold. Get the codes read!

 

Well at this point I don't want to drive the car, unless its straight into the mechanics hands. I suppose I can just wait to have them read when he does the work...

its 75k miles, what else should I have done while in his shop?

1) spark plugs
2) ...

 

Actually the plugs should easily last to 100K, but you can change them if it will make you feel better.

I would put a transmission fluid replacement near the top of the list. Also if a coolant flush and brake fluid flush have not been done in several years, that would be wise. Check the condition of your belt.

Also a brake and suspension inspection.

 

Is the transmission fluid still $500 a gallon?

 

Secondary tensioners don't begin to fail. They fail period. Some have been very lucky and the pieces have held together long enough to avoid piston valve clash.

 

I had a rough idle and "limited performance". Local guy said it was spark coils, after he had it a week I took to dealer. One tensioner flat plastic part was actually broken and both spring housings were severely cracked just waiting to let go. I don't know what code they got, but they knew what was wrong. Only 64k miles, my '01. Running fine now.

 

It sounds like maybe one of the exhaust cams skipped a tooth. You were lucky, although I'm sure it didn't feel like it when you got the bill.
RJ_______________
97XK8 Conv. 85K mi

 

Correct. Bill was close to $2k, but at least it was done right and car runs good. Surprised at only 64k miles,though. They said the new tensioners were the 3rd generation, but I didn't see the new ones to compare. I do know how lucky I am. I don't know how they diagnose this, except by experience and visually inspecting the tensioners.

 

sgparnes, in your case did you only replace the "secondaries" and not the primary sleeves?

I'm only gonna do the 2nd's as its $1,350 vs. 3,000

 

I just wanted to check back in with the results.

The shop, which has replaced several tensioners before, said "I don't hear any clatter in the front end" and that at 73k miles its not Urgent to take her apart now. Also they said that since this car is driven <5,000 miles a year a transmission flush can be delayed a few years...

We did find one thing, the repetitive "clunk-clunk-clunk-clunk" heard from the front of the valve cover case when letting off slight throttle is:

the little oil recovery solenoids opening and closing. aka its a normal sound.
That was the only sound which had been worrying me, I was not able to pinpoint it myself though.


The slight idle surges were caused by me taking a mil or two too much slack out of the throttle cable. The throttle potentiometer wasn't falling back to exactly 0%.

 

Very bad advice on both accounts. At the very, very least you should have the secondary tensioners replaced.

 

When it starts to clatter you will probably be too late.
I'd get another opinion.

 

I've got the JTIS installed and running here on my pc. I may as well remove the valve covers and inspect it myself.

are the latest generation tensioners all metal? ergo if I see a plastic shoe then it needs replacement? not having the tools, I'd take it back to the shop if they are old style...

 

The new ones still have plastic outer shoes (with a metal core), but the bodies are clearly metal, as opposed to plastic for the old ones.

 

Here's a new one


and an old one

 

//Whites right very bad advise on both accounts "REPLACE SECONDARY TENSIONERS" They have gone out on vehicles with less than 30000 miles. Here is one page.
Jaguar XK8 Engine Problems
Good Luck

 

Well I summed up vast amounts of courage and decided to remove the valve cover so I could take a look. After having spent about an hour fiddling with the back bolts I finally wrestled the cover free and peeled back the facade. Like Indiana Jones I peered into the darkness hoping to see a faint glimmer of silver; a faint glimmer of hope.

Damnit, they are orange plastic... And its got a crack running along the stamped numbers. And the primary tensioner 'shoe' is also plastic.



Looks like here's the tensioner set for 140$
http://stores.christophersforeigncar....bok?category=

 

the Ford part number for these is kicking round the forum somewhere, 40-50$ each. Ford used an AJ unit in one of their cars, Lincoln LS/Tbird?

You can also save a bundle by reading about the zip tie method on the forum instead of taking to the shop.