Not sure if anyone else had gone down this path, but I am hopful that I found replacements for the o-rings in our PCV system. This would be the two o-rings on the PCV valve where it goes into the cam cover, and the o-rings at each end of the corrugated hoses. Of course they are not a standard size, it would be silly to think anything would be that easy on a Jag!

The closest match I could find from measuring the originals are 2.65 CS x 14 ID mm (hoses) and 2.65 x 16 mm (PCV valve). I've ordered a sample of these and will try the fit on my car. If they fit this will hopefully save others some money and headache. No reason to replace $150 worth of parts just for a leaky $0.20 o-ring (all assuming the corrugated hoses themselves are not broken).

Will post back results asap!

 

good man, always good to have alternatives.

 

I forgot to follow up on this thread--

Ordered the 2.65mm CS x 16 mm and 14 mm ID from The O-Ring Store LLC, We make getting O-Rings easy! These are exactly the right size for the PCV valve and the hose from the PCV to the TB. The cam breather on the other side of the engine uses a smaller size ID, I didn't replace those since they seemed to still be in good shape. If I pull those off I will update with the correct size.

Replacing the o-rigns on the PCV cured a world of problems with my XJ. I think it was running lean for quite some time. Caused lots of pinging, poor shifts, and a lean-surge feel on the highway. Yet never a lean code or CEL. After feeling how much tighter the pipe and valve fit with the new o-ring, there's no doubt the old rings were shot.

 

I was just thinking of you and the pinging problem and didn't realize you had found a solution, actually the exact same solution, only my vacuum leak was from another spot. One of the VVT solenoid seals gave up completely on my car. It was pouring oil down the side of the motor, which would explain how bad the leak was because this isn't a spot where oil is under pressure. I was just trying to fix the leak and didn't even think of the pinging issue at the time. I'd been fighting it for so long with 2 doses of BG44k that barely helped. I literally drove to get the seal, popped it in while in the parking lot of the dealer, and drove off. It was pinging a bit from being hot sitting in traffic at part throttle on the way there, but none at all after the seal was replaced. The car also runs much stronger to redline now. It definitely was causing a lean condition before. I never had any codes either.

I always worry about the breather hose o-ring design. So far every time I've had to take them apart I grease them to keep them soft and sealing. Looks like it would be beneficial to pick up some O rings to have around just in case.

 

Funny enough I just replaced those 2 cam sensor seals on my engine as well. They had just started weeping. Sadly the new PCV o-rings did not cure my pinging after all. It definitely fixed the air leaks--my LTFTs are down to -6% from where they were previously pushing -15 to -18% (with an occasional lean code).

The new MAF (paid Jaguar for diagnosis, this is what they came up with) did make a big difference in shifting, but after the PCM learned its parameters, it was back to light throttle pinging.

After seeing how sludged the intake manifold was when I replaced those gaskets, I'm sure that my combustion chambers are carboned up like crazy.

 

Is this carbon buildup? a problem on SC cars as well?

I haven't noticed pinging (yet)

Appreciate the o ring specs

 

Also insure the o-ring on the dipstick is still sealing the tube from atmosphere, (need to create an airtight seal) as well as the seal at the bottom of the oil filler tube that screws into the cam cover.

 

So you are still chasing this? I didn't expect the pinging to be affected by replacing the VVT seal, it was a night and day difference. It hasn't pinged at all since. I was starting to think I'd need to replace the MAF.

 

Mhamilton,

when ordering the o rings was it part # N2.65X014 at $0.22 each.
N for nitrate rubber, 2.65 for CS cross section, 014 for ID inner diameter of 14mm.

You had 2.65mm CS x 16 mm and 14 mm ID, but with a CS of 2.65 and an ID of 14 the outer diameter would be 19.3 (14+2.65+2.65)

 

Two separate o-ring sizes: larger 2.65x16 is for the PCV valve to cam cover. Smaller 2.65x14 is for the PCV hose at both ends. I didn't spec the OD. Also, the o-ring on the PCV breather hose (opposite cam cover) uses yet a smaller size--I didn't remove those or spec them.

Yes and no. I gave up chasing this after the money I've already thrown at the issue. The pinging just doesn't change. I can get it to go away short term, but whatever the PCM is adapting to causes it to come back. I could replace more seals (oil fill cap and tube, dipstick oring, etc), but I'm sure it wouldn't make a difference long term.

I really thought that the Jag dealer would be worth the cost to fix this issue, with the tools they have access to. After paying them for the diagnosis and replacing those parts, I'm no better than where I was before. True to form at my dealership, overpriced oil change monkeys.

 

That's crazy. I'm still leaning towards a vacuum leak after my experience. I haven't had a hint of ping now after driving it 4 days now and I never disconnected the battery or reset adaptations in any way.. Didn't you recently do the the thermostat housing? Maybe the seal on the intake manifold isn't sealing well on the underside where it's hard to detect.

 

Hopefully yours stays fixed. I might try replacing the oil fill tube/cap next--even if only to stop the slight oil seepage. Never seen an engine where removing the fill cap while running will stall the engine.

The thermostat wasn't me... The intake gaskets are all new from when I pulled the manifold for the coolant hose in the valley.

What conditions caused your engine to ping? On mine it's been very consistent--fully warmed up engine, light throttle, around 1750 rpm. No problem with heavy loads, it's light throttle cruising or small throttle accelerations around town.

 

Yep, my ping was identical, sounded like a popcorn popper on slight inclines at that RPM. At one point I was driving uphill in Death Valley and it pinged so hard I almost didn't get up the hill. While driving back I stuck my foot in it to pass a car and hit 90+ mph. At that point it broke up at higher RPM and wouldn't accelerate any faster. It started to develop a really rough high RPM idle on cold days and that went away immediately as well. My oil leak was bad and forming a small puddle on the ground from the amount splashing up on the VVT seal and then running down the side of the block.

What I'm finding is that if you have any oil leaks at any spot that isn't under pressure, it's going to be a vacuum leak. Most cars these days will see removing the dipstick while running as a vacuum leak. My GTO would almost die doing this.

 

The way in which the Denso system works, is that all air has to be metered by the MAF sensor. The intake to the crankcase on bank 2 is post MAF. Any breach of the crankcase itself, like those things which we have been talking about, allows air to be taken into the PVC system without it being drawn over the MAF sensor, like the huge leak taking the oil filler cap off for example. This creates a lean condition on very low partial throttle. Think of it as a sealed system.

When I was at Chrysler Corp., the high dollar, continuous flow fuel injection system used in the early 80's Imperials, Lee's pride and joy, required such a sealed system, and if you took the air cleaner loose while running, it would instantly die. This actually happened in one of Iacocca's demonstrations to some very elite customers, one of them spun the wing-nut off to lift the top off to see the spray bars above the throttle plates, and when it fell on it's face, in embarrassment, Lee demanded that they place a large instruction sticker on the air cleaner top, and a locking band around the top of the air cleaner so no one could do that again. LOL

 

This is why I stopped chasing this problem. I don't have any oil leaks that leave drips--the worst is a "slight film" around the oil fill tube that attracts a little bit of dust on the cam cover. I feel like I'm chasing shadows.

One thing I just thought of--I have never checked my dipstick tube for a vacuum leak. The dipstick doesn't seat very securely, my other cars you have to yank on the dipstick to unseat the oring. How secure are the ones on your Jags?

 

Mines a tight fit. It takes a solid pull to unseat the dipstick.

 

Thanks! I will see if I have a new o-ring to fit on mine. I know for sure mine's somewhat loose, depending what direction you install it, it will almost push itself back out.

 

I know this is an old thread, but wanted to say thanks! I had a leak on my passenger side cam cover and just assumed I'd be replacing the gaskets at some point. After a closer look it was the PCV spraying oil all over the cam cover. Ordered the 2.65x16 & 2.65x14 o-rings from the o-ring store and no more leak! Also fixed a slightly wandering idle which is a bonus. I didn't have smoke (that I was aware of), but glad this ended up being a cheap and easy fix. Had to order a bunch to meet their minimum order so should be able to replace these a few more times if they decide to leak again. Thanks again!