Hi - my first post! Hope to meet local XK8 owners in the Raleigh area - message me - would do me wonders to see a working specimen to compare with what I am looking at in my garage!

This xk8 has MANY issues - it starts and runs, but idle is very crappy and flutuates, or runs very high idle. Computer is complaining of anti-lock and stability control failures, and there are no power brakes.

I think I would like to solve the basic problems first. I assume that my lack of power brakes is loss of vacuum. I have tried to trace the plastic vacuum tube at the booster, and it disappears behind the drivers side firewall - appears to go to the passenger side.

On the passenger side, I cannot be completely certain that the plastic tube I see that disappears under the ECM is the same tube. If so, why is it going into the fender?

I did try to trace the vacuum lines from the throttle body, but the only vacuum line I see seems to go to some sort of vacuum switch on the driver's side wheel well, and it branches vacuum out from there - but none of the lines appear to go to the brake booster.

I am getting old and probably just blind! Where are some vacuum diagrams? I installed the jtis and it only shows diagram of the brake booster and the vacuum line, but says it goes to the intake elbow....I see no lines or nipples for lines on the intake elbow.....I must not be looking at it correctly.

I don't have my camera with me tonight, but I can post some pics of what I am looking at if that would help!

Jamie

 

Hi.


Agree that JTIS is somewhat confusing regarding brake vacuum line. As far as I understand it is as follows:
- Right hand side throttle elbow (blw throttle body) are two vacuum connections. The bottom one with a hose shrouded in silver heatshield is for the brakes. From here it goes further right, in blw the ECM, swings around to the left blw the scuttle panel, goes all the way over to the left side where it is connected to the brake booster. If this is disconnected or broken, you will have no pwr brakes.
- If it is broken or disconnected, this might also explain your poor idle as you will have a massive vacuum leak.
- Your ABS warning is covered by numerous posts in the FAQ section.

 

Oyster - you described it perfectly! If it were a snake it would have bit me!

Seems like the connection at the intake elbow has snapped, and the other side of the pipe that connects through the ecm compartment is also cracked.

Any suggestions on where to find a replacement part? For the sake of moving on with my troubleshooting, I will probably just replace with some hose and t-connectors.

Thanks again! Now, going to post about my high idle....

 

Hi.
The hose should be available from SNG Barrat. It is not very expensive.