Hi all, I got a p0171 code (lean system bank 1) on the xjr and have been diagnosing all the vacuum hoses through a smoke test, along with cleaning the MAF.

Found one leak on the intake pictured below, where the PCV hose attaches to the intake. Are there any solutions to seal the hairline crack since it’s small and I would hate to replace the whole intake for it? The pcv hose itself is fine, just this nipple is the issue

 

Bummer. If you want to try to save it you have four approaches.

1) Buy some self-fusing silicon tape and with the assembly together wrap it up good and tight. Maybe put some RTV over the entire area before hand, let it fully cure, and then try wrapping it. I would start in the middle, wrap as low as you can go and then reverse and wrap up an inch or two. I would not have any RTV on the inside for fear that it could peel off and get sucked into the system.

2) Try to find a replacement fitting and pull the existing one from the intake and replace. Finding the correct fitting would be hit and miss and depend on what kind of parts you have laying around. It looks like the current fitting is glued in so it wouldn't be too hard to replace - finding a replacement is the issue. Many fittings are the same from car to car, with the piping dimensions, length and angles being the only difference.

3) You could insert a thin walled sleeve slightly longer with the added length residing inside the intake. The outside diameter would have to be the inside diameter of the existing fitting. Looking at the picture it appears there is a circular protrusion that would restrict insertion. This would need to be smoothed down. Then clean the area, rough the area up and glue the thin walled sleeve with some sort of plastic epoxy. Rough up both the intake and sleeve so the adhesive has some bite. If you have access to the inside of the intake - you can do a nicer seal job. While the glue is curing I would wrap the "nub" tight to keep it from expanding - maybe even do this before you install the sleeve.

My concern with this approach is the sleeve failing and falling into the intake - although I don't know if this could cause additional issues if it falls in other than it coding again. On some intakes which have moving parts - this could cause a jam - don't know the insides of the intake on your car. So the work around - drill a hole through the repair and send a pin all the way through and grind it flush so that the PCV pipe can sit correctly. This will prevent the tube from falling down. Pin cannot go anywhere because of the PCV pip fitting. If you had more material to work with you could "top hat" it, but I think the PCV pipe would not fit correctly. Work around is to take more material off to compensate - but at this point it has become a major project. Realistically if you are satisfied with the glue selection you could just glue the sleeve in and be done with it.

Final idea on this option - use the sleeve, keep the circular ridge as it will prevent the sleeve from falling and use your glue to seal the area below the sleeve all the way down. Just keep it smooth and as thick as possible.

You can look around for some plastic or metal pipe that is close but slightly larger and sand it down so it is tight. Heat the plastic very slightly when you insert the sleeve. You have to make sure you do not make the dimensions bigger or the PCV pipe will no longer fit.

You can also remove the fitting and do the repair if your examination says it would work. This will make for a pretty good repair.

4) You can glue the entire assembly together and worry about servicing at a later date. At said later date you can cut the new PCV piping at a suitable spot and couple/splice it together so you can service it.

 

A soldering iron ran along the crack, inside & out.
Melts the plastic in the crack, or welds it closed.
Then fill the void in the seam with the two part epoxy, or glue for plastic repair.
Have used this method to repair plastic on motorcycles for years.
Welding plastic sounds rather odd, but it can be done.

 

Thanks wingrider I think that welding could work for this. Could you clarify what you mean by filling the seam with epoxy after welding? which seam? Won’t the crack be closed after welding?

 

Closed but still visible, the two part epoxy for plastic, fills in the void created from the plastic melting together.
I have seen one guy use old tie wraps as filler much like welding, with brass.
Adds a bit of strength to your weld.

 

Did it work? If not the air tube intake from the 4.2 S Type part # XR849560 can be used instead of one from an XJ8.
And you'll enjoy the savings, mine was about $67 and woks great

 

Yes! Thanks to wingrider, the welding and filling with a plastic zip tie worked great. I ordered caldoofys intake anyway but welding repaired it back to normal