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engine was running just fine. Suddenly there was a lot of blue smoke coming out of RHS (passenger US). Mostly when put under load after idling.
looked inside throttle bodies and oil literally ran out of RHS.
All I did recently is blow off the top of the engine with compressed air.
did I knock loose a PCV line or something?
thanks in advance for any help
the car has 50k miles and has been sitting inside for 5 years. Prior to that it was driven less than 100 miles after another couple of years of storage
well start by inspecting PCV system!
some times vacuum can pull oil from the rubber knob on front of left valve cover , take a look!
i had some oil problems relating to the factory PCV system!
so achange was required, a cheap oil catch can, did the trick ,no more oil in mostly RHS, odd it ends up over there but is what is!
im looking for a pic , also greg has a thread about catch cans! oil catch can, goes between cam cover breather and inlet manifold vacuum hoses!
well start by inspecting PCV system!
some times vacuum can pull oil from the rubber knob on front of left valve cover , take a look!
i had some oil problems relating to the factory PCV system!
so achange was required, a cheap oil catch can, did the trick ,no more oil in mostly RHS, odd it ends up over there but is what is!
im looking for a pic , also greg has a thread about catch cans!
thanks for The reply!
Not seeing the ‘rubber knob’
Is it behind the fill point on the cam cover?
it happened very suddenly, and it’s not a little smoke, it belches it out!!! Was fine yesterday when I drove it 30 miles or so.
No smoke on startup, only smokes when under load and after coasting. Not so much when revving in park.
yes in front of fill cap left side, also a very high vacuum when crusing and throttle let off, sucks the oil into vac pipes!
the can will hold much oil but every so often gotta take and drain it!
ron
well start by inspecting PCV system!
some times vacuum can pull oil from the rubber knob on front of left valve cover , take a look!
i had some oil problems relating to the factory PCV system!
so achange was required, a cheap oil catch can, did the trick ,no more oil in mostly RHS, odd it ends up over there but is what is!
im looking for a pic , also greg has a thread about catch cans! oil catch can, goes between cam cover breather and inlet manifold vacuum hoses!
thanks for the pic!
is that the factory catch can I’m looking for, or an aftermarket one that I need to add?
If there is oil in the A Bank (RH side Inlet), then the tranmission Vac Modulater is #1 failure cause.
OK, trans oil is usually White-ish when burnt, BUT, old age fluid can have a Blue tinge to it.
The small vac hose is attached to one of teh spigots at the rear of that Inlet manifold, locate it, unplug it, CAP that spigot, and try again.
LOOK CAREFULLY inside that hose for oil trace. If there is oil trace, problem found.
BUT
That modulator controls gearchange points, so DO NOT drive it too much IF it has failed.
Its a standard TH400GM modulator, nothing specific at all.
If that car has sat, and had so little use,I strongly suggest replacing ALL the rubber type hoses under the bonnet. Fuel, Vac, Coolant, they will be waaay to old to be reliable now,
Your car, Your choice.
If I unhook the metal pipe to the engine breather filter, just temporarily, can I make sure that it’s oil coming from the PCV system before I install a catch can?
Take the "pigs snout" off, CAREFULLY, they have a habit of crumbling from age.
There is a small capsule filter in there, remove it, clean it in solvent a few times..
Check the inner bore of that steel pipe that goes to the air cleaner back plate. It MAY have an oily film inside, that is NORMAL..
Pop the B Bank air cleaner cover, check for oil residue in there, that is also NORMAL, but copious amounts of oil, NO.
Pop the filter element, open the throttle by hand, reach in with your finger, and wipe the innards, probably "black V12 Goo", so clean with a solvent soaked rag as best you can.
Repeat on the other side.
Remove the "Y" pipe across the "V" and inspect that for oil inside, there should be none.
These inlet manifolds are "oily" on the inside, more so in your country, where emissions requirements dictates so much rebreathing.
Old trans fluid mixing with that "oily goo" will be Brown.
Take the 30 seconds, pop that trans vac hose, and look inside, NO oil, good to go, Oil inside, modulator needs replacing.
The fact you were driving it, then a sudden smoke screen, still heads me to that trans modulator.
After all those years sitting, and now woken up, many items are going to do strange things. Some instantly, more later on.
Last edited by Grant Francis; Oct 14, 2020 at 06:16 AM.
there are 4 vacuum lines into the rear of the manifold. One is very different, it is hard plastic, much smaller diameter and it’s clear, tinted red.
It goes into a 1 1/4” dia corrugated pipe with other wires, turns 90 deg and goes thru a bulkhead in the firewall.
you can see the fluid in it! Is this the trans modulator line?
I see the modulator is on the bottom, right side of transmission. As soon as I can pull it out of garage and get under the car I’ll see if that red plastic line is attached to it.
Is this different, clear line from the factory or a modification someone made to it?
It is very hard to see form the photo where the rubber elbow on that hard line is attached to the manifold; but assuming it is, then that line - which I agree seems to have tranny fluid in it - indicates that, as Grant diagnosed, the moduator is toast. As follows:
That line looks like it is the vac feed to the aircon system operating various flaps etc
That line is attached to A bank manifold cabin end, the same end of the same manifold that the gearbox modulator vac line is attached to. One of the other vac lines on the manifold is the tranny modulator one
It looks pretty likely to me that tranny fluid is coming up the modulator vac line into the manifold and also making its way out down the aircon vac line.
The modulator vac line goes from the manifold down in front of the firewall and to the gearbox where it is attached to the modulator, as in this pic. The modulator is a push fit being held in by a small bracket and a single bolt. It must have an O ring in it when refitting, which the new one should be supplied with. Best to buy a new vac line too. The old one will be shot. The modulator is on the left in the photo (the gold coloured thing sticking out of the side with the blue vac line running down to the elbow plugged into it). This photo is from the front of the car looking rearwards, the modulator is on the RHS and is easily accessible from under the car. close up of modulator with vac line not yet attached.
thanks SOOO much! I remember you and your awesome XKR mods from about 10 years ago. I lost access to my old email and started as a new user. I also have a 2001 XKR Silverstone. Still have both, just starting to revive the XJS first.
Yes, that hard line is one of 4 Vacuum lines, all going into the rear of the A manifold at the same place.
headed to parts store for the modulator, about $15 here for the standard GM one.
Not guilty on the XKR stuff, someone else!
I forgot to mention, and please accept my apologies if you have bought the wrong part. My reply was assuming you car has the GM400 3 speed automatic gearbox. As a 1992 it might (or might not) have the more modern 4 speed box Jaguar fitted to later cars. If it does have the 4 speed, I have no idea if the modulator setup is the same or not. The diagnosis stays the same though!
catch can mounted.
rich this may be of help)MAYBE).
pic of my catch can mounted and seems now i dont get any oil in manifolds,either side!
im also using a GM 700R4 trans, has NO vacuum to it!
have a quiet read of the alignment sticky I wrote years ago. Its at the top of here.
Too many "aligners" will stuff that simple process up, lazy that they be, and then wishbone bushes fail in no time, and once again "The Bl&&dy Jaguar" gets blamed for that.
there are 4 vacuum lines into the rear of the manifold. One is very different, it is hard plastic, much smaller diameter and it’s clear, tinted red.
It goes into a 1 1/4” dia corrugated pipe with other wires, turns 90 deg and goes thru a bulkhead in the firewall.
you can see the fluid in it! Is this the trans modulator line?
I see the modulator is on the bottom, right side of transmission. As soon as I can pull it out of garage and get under the car I’ll see if that red plastic line is attached to it.
Is this different, clear line from the factory or a modification someone made to it?
Maybe its been mentioned BUT that orange tube is as it's supposed to be... That is the vac signal tube going to the Marelli ECU in the RH foot well...
Oil in throttle body
