O.K., I'm trying to track down the source of a lean condition on the right bank of my '99 XK8 4.0. Getting persistent P0171 among others after a complete tensioner & chain replacement at 67,000 miles. I'm checking the usual things but need to know just how to go about changing the VVT seals. Parts Geek has them at a cheap enough price so I may do them while I'm at it since I suspect that at least one if not both may have been damaged when we took the valve covers off.

Can't find a thing in the svc manual except how to remove the unit itself.

 

If you still had the cam covers off you could just pop them out with a socket. With the covers still on, you can get them out, but will be a bit tricky. Depends on how stuck on they are. You don't have any vacuum leaks anywhere ( air intake, part load breather pipe, etc ) ?

 

Easy peasy- gently pry them out, clean the area and press the new ones into place. Might want to refrigerate them first so the slide in easy. Also, I found replacement plugs for the VVT's on Amazon- now mine are "clicked" into place instead of just pushed on.

 

The part load breather has been replaced within the past 3-4 months with new one and the air intake tube has been thoroughly checked and any suspect area heavily sealed even if not actually broken through.

I suspect a slight air leak as the car runs without hesitation once I get a 1/4 to 1/2 mile down the road after a stoplight or getting caught in very slow traffic for a minute or two and the Restricted Performance light goes out.

What's got me is that it looks and feels as if what is around the VVT's is metal or some hard plastic seal but I haven't done a really close inspection yet as I'm lining up options. I don't drive the car all that much as we usually take the XJ8 my wife drives and she doesn't much care for the butt on the road low stanch of the XK so I've been less than concentrated on rooting out the problem.

I've been having a problem with my SDD software (ver 1.30) so I'm going to try to get some fuel trim data with my OBDII program and see if I can make heads or tails out of what it's showing me.

I'd as soon not have to remove the valve covers as that's a pain in the tail and at 70 with 5 herniated discs and 2 all metal knees this old gray mare and what I used to be so I'll see if I can finagle the VVT seals without having to remove the VC's

 

Just put a piece of tape on a flat blade screwdriver (to make it dull and not scratch anything) and pry the seal off. Nothing to it.

 

Having taken a much closer look at them this afternoon I was able to see the thin outline of the seals that had been obscured with built up grime, etc., and can see where careful use of a pick worked under an edge will allow them to be pried up a bit at a time so I think I'll replace both as long as I'm screwing around.

I really think my problem is elsewhere and could possibly be a failing injector or plug/plug wire combo. I replaced a coil on the #4 plug due to a P300 & P306 code and the P306 went away and has stayed away leaving me only the P300 code, so I'm getting closer every time<G>


Still have the P0171 however and I've checked the EGR and other assorted vacuum hoses and can't find any potential leaks in any of them. MAF sensor has been re-cleaned even though the code is reflective of a POST MAF problem.

I just keep chipping away at it.